E24 89 635csi PROBLEMS

[Aviveiros27]

Hello all. Had this car for about 2 weeks and having some weird issues. So the car starts every time on the first crank, and stays running, however the idle does sometimes spike a little but and dive. But the big issue is a weird hiccup when driving. It happens when pulling away from a stop, and under heavy load. Most times when pulling away, the car dies or almost dies if I don't give it more gas. And if I try a 3rd gear pull will jitter multiple times in a row around 3k rpms. Someone help. Getting really annoying as its almost impossible to drive in traffic. car is automatic.

[ldk]

Things that come to mind--rotor and distributor cap, fuel pump relay, vacuum leaks. Check out http://hiperformancestore.com/Motronic.htm for troubleshooting.

[1986series6]

Engine wise +1 by LYK NU 6.


Tranny wise:
Had the same problem for 30 years until I did a 5 speed swap.
Had it checked out, told me it was the TCU (Transmission control unit) behind the knee bolster on drivers side.
Mostly happened on the 1 to 2 shift, I just lived with it by not stomping the go peddle in E mode.

[Aviveiros27]

So I did more looking today and noticed an obvious disconnection at the tps, and someone placed a weird cap over the receiver on the tb. Now the car idles perfect at 750 rpms and the kick down works now. However the car still bucks when coming to a stop and bucks around 3k. I also have noticed that if I slightly touch the transmission selector, the dashlight for the gear selected shuts off. If I pull it down ever so slightly the light stays on.
Update: Idle sucks. Car starts right up, ha's a steady idle for like 5 seconds, then jumps and stalls. Someone please help, I need a expert over here. Anyone in the southeast Massachusetts area??

[Aviveiros27]

So i replaced the coil, and spark plugs. Still have to do fuel filter. Checked the ecu, and the the ecu is fine, CPS is fine,and all grounds are fine. Any other things to look at. Car us definitely at its worst right now: doesn't idle at all, stalls, smells like fuel (really rich).

[ldk]

It doesn't help that you started two threads on the same symptoms. However, to summarize, it looks like you replaced coil and spark plugs and have checked and confirmed the following to be OK: ECU, grounds, icv, afm plug, and cts. If there are other things you've done and confirmed to be OK, please list them here. In particular, have you replaced the distributor rotor and cap and the relays like I suggested?

[Bert Poliakoff]

Pull the dipstick and see if that affects idle. If it doesn't, you have a vacuum leak somewhere. If it does, you can rule out a vacuum leak issue.

[Aviveiros27]

It doesn't help that you started two threads on the same symptoms. However, to summarize, it looks like you replaced coil and spark plugs and have checked and confirmed the following to be OK: ECU, grounds, icv, afm plug, and cts. If there are other things you've done and confirmed to be OK, please list them here. In particular, have you replaced the distributor rotor and cap and the relays like I suggested?
I haven't done the dizzy and cap yet but I didn't bother because the symptoms are just so inconsistent. I opened up the ecu to try to find any cold solder joints or corrosion and there wasn't anything. I still have a strong feeling it's a fuel delivery issue within the filter.

I guess it would also help to know that before I purchased the car, the PO told me it sat for 3 months because he stores it for the winter.

[1986series6]

"I still have a strong feeling it's a fuel delivery issue within the filter"

Sitting for 3 months will have absolutely nothing to do with your problem.

Before you guess that it might be the fuel filter, get a pressure gauge

on the rail to monitor the pressure. If it stays somewhat steady while

running, the problem won't be fuel from the delivery. Maybe @ the injectors,

don't guess @ this stuff. You have to do methodical testing or you'll drive us crazy.

BTW, did you receive the TPS and did it work any better?

Bob V

[Aviveiros27]

"I still have a strong feeling it's a fuel delivery issue within the filter"

Sitting for 3 months will have absolutely nothing to do with your problem.

Before you guess that it might be the fuel filter, get a pressure gauge

on the rail to monitor the pressure. If it stays somewhat steady while

running, the problem won't be fuel from the delivery. Maybe @ the injectors,

don't guess @ this stuff. You have to do methodical testing or you'll drive us crazy.

BTW, did you receive the TPS and did it work any better?

Bob V
I did receive it and the micros witch does seem to click better, but the idle is still terrible. So I'm not sure.

[ldk]

... I opened up the ecu to try to find any cold solder joints or corrosion and there wasn't anything...



A word of caution on inspecting the ECU. I once had problems with mine. I opened it up and re-flowed a couple of suspect connections. Didn't work. I opened it back up and re-flowed every single connection, regardless of what it looked like. That worked.

Best test at this point is to get someone local to loan you a known working ECU. Next best is to buy one, maybe on eBay, that the seller claims works. You'll want a working spare for the future anyway, like you want working spares for lots of things--especially the aforementioned relays.

[slofut]

I haven't done the dizzy and cap yet but I didn't bother because the symptoms are just so inconsistent. I opened up the ecu to try to find any cold solder joints or corrosion and there wasn't anything. I still have a strong feeling it's a fuel delivery issue within the filter.

I guess it would also help to know that before I purchased the car, the PO told me it sat for 3 months because he stores it for the winter.

So you're troubleshooting some aspects by "assuming". Check this link and read posts 11 and 12, don't just look at the pics...

https://www.bimmerforums.com/forum/showthread.php?2376876-2-1-2-Years-and-I%92m-still-trying-to-solve-my-1984-33-Series-Problem-(Long-Post)&highlight=slofut+no+start

[Aviveiros27]

So you're troubleshooting some aspects by "assuming". Check this link and read posts 11 and 12, don't just look at the pics...

https://www.bimmerforums.com/forum/showthread.php?2376876-2-1-2-Years-and-I%92m-still-trying-to-solve-my-1984-33-Series-Problem-(Long-Post)&highlight=slofut+no+start
Thanks for the tip. That will be my next move. Also if any of you know anyone or if anyone on here is from around Massachusetts with a spare ecu that would help a lot, thanks.
Is any 179 ecu direct replacement?
Any help identifying these plugs as well, I went to touch these and they crumbled.646357
646358
646359I

[Aviveiros27]

It doesn't help that you started two threads on the same symptoms. However, to summarize, it looks like you replaced coil and spark plugs and have checked and confirmed the following to be OK: ECU, grounds, icv, afm plug, and cts. If there are other things you've done and confirmed to be OK, please list them here. In particular, have you replaced the distributor rotor and cap and the relays like I suggested?
So I just did the cap and rotor, and at the first start up the car ran perfect. I went to put it in reverse and as soon as I pressed the gas it stalled. Started it and unplugged the tps and then pulled off without issues. Drove for about 2 minutes until most of the stalling symptoms recurred but on a lesser scale.

[Aviveiros27]

Here is a video. Car still has problems. Can't figure it out.
https://youtu.be/WnFfWai4EJ0

[Kinetik]

150 and 179 ECU are on the same page. although the 179 ECU is way better.
https://www.programainc.com/item_detail.aspx?idproduct=167&idcategory=39&sf=

This is currently onsale for 69 bucks.. steal if you ask me..

[Aviveiros27]

I think last resort is the ECU as I just replaced ignition wires and that did nothing.
To date I've done:
Spark Plugs, Dizzy cap and rotor, spark plug wires, ignition coil, coolant temp sensor, tried a different tps, cleaned icv, cleaned and inspected the afm.

[Kinetik]

You really need to get some diagnostic tools on this one my man.

other wise this meme sums up this thread.
647834

[Aviveiros27]

I'd disagree with that meme. All the parts I've replaced needed replacing anyway. Cts was out of spec, ignition wires were burnt, coil was way out of spec, spark plugs were fouled, and the rotor and cap were original parts. So..nothing has been wasted. Just unfortunate it didn't happen to be any of those.

[Nullified]

It still hasn't solved your problem though, so the meme does hold some truth!

Hope you get to the root cause of the problem soon, one problem with these cars is that you need an old school mechanic and they are getting scarce. The younger generation of mechanics are very proficient at OBD-diagnostics and then replacing parts according to the warranty manual.

I'm especially interested what the fix will be.

[Aviveiros27]

It still hasn't solved your problem though, so the meme does hold some truth!

Hope you get to the root cause of the problem soon, one problem with these cars is that you need an old school mechanic and they are getting scarce. The younger generation of mechanics are very proficient at OBD-diagnostics and then replacing parts according to the warranty manual.

I'm especially interested what the fix will be.

As far as testing with a multimeter, and checking hundreds of pages in multiple repair manuals, and studying wiring diagrams, I've done just about everything I can do within my knowledge. There's a guy near me who's locally known as Bobby Bimmer, and he's done these cars for 40 years, but he told me he doesn't work on other people's cars anymore. Too bad.

[Nullified]

Too bad indeed, so close but yet so far... Terrible to be working on solving a problem and not being able to solve it especially after the amount of hours you've put in it. Damn...

[DesktopDave]

So I did more looking today and noticed an obvious disconnection at the tps, and someone placed a weird cap over the receiver on the tb. Now the car idles perfect at 750 rpms and the kick down works now. However the car still bucks when coming to a stop and bucks around 3k. I also have noticed that if I slightly touch the transmission selector, the dashlight for the gear selected shuts off. If I pull it down ever so slightly the light stays on.
Update: Idle sucks. Car starts right up, ha's a steady idle for like 5 seconds, then jumps and stalls. Someone please help, I need a expert over here. Anyone in the southeast Massachusetts area??

Have you checked out the Motronic troubleshooting page at hiperformance (http://hiperformancestore.com/Motronic.htm)? There's an updated version here (https://www.hpsimotorsports.com/motronic-). It's brilliant, very methodical. Saved me like a year of frustration. I was so happy I bought a set of silicone vac hose from him. I print up a copy, put it in a binder, remove the parts that don't go with that particular motor, and leave one in every car. I even give them away with cars I've sold!

You haven't tried a smoke test, have you? Sorry if you have and I missed it - just catching up on your thread. The Motronics are very particular about maintaining proper vacuum & voltage. I had a motor once that never idled well, the cam seal was damaged. That took some time. What about the alternator? Nice stable voltages? What kind of VDC ranges are you seeing at idle and 3K RPM?

Did you check the inhibit switch inside the gear selector? I've seen a few threads about them going out. You swapped the fuel filter, is the in-tank lift pump working? I had one that a wire had gotten loose inside the housing.

If the car is running really rich I'd also suspect the coolant temp sensor wiring harness. I know you replaced the CTS, but BMW had a recall campaign where they soldered an inline resistor inside the boot. It eventually fails, open cicuit, then the car never goes to closed-loop and runs rich.

Those wiring connectors on the fenders look like the ABS sender plugs, they always do that.

That other 3-wire connector that's fallen apart is either the position sensor or speed sensor. Both are normally clipped into the rear intake manifold support rail. They're both very important, but that plastic always crumbles. I usually just tape them securely together. Don't get the terminals mixed up. 1&2 are the signal (should ohm out to about 1K ohms IIRC) 3 is the sheath. It's a floating ground, so the 1&3 and 2&3 pairs should ohm out really high. Some ohmmeters will read out like 10K maximum, others will go infinite (open circuit).

[Kinetik]

I forgot about that one its a really good one site. Great suggestion Dave

[Aviveiros27]

Have you checked out the Motronic troubleshooting page at hiperformance (http://hiperformancestore.com/Motronic.htm)? There's an updated version here (https://www.hpsimotorsports.com/motronic-). It's brilliant, very methodical. Saved me like a year of frustration. I was so happy I bought a set of silicone vac hose from him. I print up a copy, put it in a binder, remove the parts that don't go with that particular motor, and leave one in every car. I even give them away with cars I've sold!

You haven't tried a smoke test, have you? Sorry if you have and I missed it - just catching up on your thread. The Motronics are very particular about maintaining proper vacuum & voltage. I had a motor once that never idled well, the cam seal was damaged. That took some time. What about the alternator? Nice stable voltages? What kind of VDC ranges are you seeing at idle and 3K RPM?


.
Thanks for identifying those sensors on the fenders. I think the 3 prong one isn't the speed sensor but rather an oil sensor of some sort. It goes directly to the oil pan. What's funky is that the car will sometimes run perfect, but then exhibit the same symptoms again shortly after.
I ended up opening the afm today to do a sweep test and resistances are all over the place, there's also a few oL spots. So I may, after all this, just need an afm, which are ridiculously expensive. It's beyond repair as the carbon track is all worn down.
My battery also has a constant charge so I'd put the alternator at the back of the paper. The only good part about buying all those parts is that I've narrowed it down to a few things...the bad part...the remaining parts are the most expensive :(

[Kinetik]

Thanks for identifying those sensors on the fenders. I think the 3 prong one isn't the speed sensor but rather an oil sensor of some sort. It goes directly to the oil pan. What's funky is that the car will sometimes run perfect, but then exhibit the same symptoms again shortly after.
I ended up opening the afm today to do a sweep test and resistances are all over the place, there's also a few oL spots. So I may, after all this, just need an afm, which are ridiculously expensive. It's beyond repair as the carbon track is all worn down.
My battery also has a constant charge so I'd put the alternator at the back of the paper. The only good part about buying all those parts is that I've narrowed it down to a few things...the bad part...the remaining parts are the most expensive :(


you may already know this but you can bend the arm to run on a new part of the track.

I do it on all my AFM's and it's worked great for me every time.

[Aviveiros27]

you may already know this but you can bend the arm to run on a new part of the track.

I do it on all my AFM's and it's worked great for me every time.
I tried to do that, but to no avail. When I did it I thought It was a surefire way too

[Aviveiros27]

ISO anyone local who wants to help me out. I'm an at home mechanic, and I basically give up. I've thrown in the towel. I've tried 2 new afm's, installed coil, plugs and wires, cap and rotor, cts. And the car will not idle right, it wants to die out. It stalls when coming to a stop. And it has zero response when pulling off (you can go full throttle and it will not pass 1500 rpms for at least 5 seconds.

[Kinetik]

ISO anyone local who wants to help me out. I'm an at home mechanic, and I basically give up. I've thrown in the towel. I've tried 2 new afm's, installed coil, plugs and wires, cap and rotor, cts. And the car will not idle right, it wants to die out. It stalls when coming to a stop. And it has zero response when pulling off (you can go full throttle and it will not pass 1500 rpms for at least 5 seconds.

Have you checked your fuel pressure at the rail and verified it's operating correctly?
Have you checked your intank fuel filter?
Have you verified the lift pump is working in tank?
Have you done a smoke test on the car like other suggested above?
Have you pulled your valve cover off an inspected the cam lobes?
Have you done a compression test/leak down test?'
Have you tried a good used/new DME?



When you installed the new sparkplugs did you verify the correct spark plug gap?
When you installed your AFM did you make sure it was the exact same part number? as different years and models are COMPLETELY differently tuned AFMS and will not play nicely with the DME

The m30 has nothing special to it. She's a good simple engine you can figure this one out yourself. But i think you should ask yourself if you've really put your efforts where they are needed to figure out whats really going on with this car.

Every post you've sent us has been about some item that you've replaced and nothing about actual diagnostic information that would allow any one to provide proper input for you back.

[Aviveiros27]

Have you checked your fuel pressure at the rail and verified it's operating correctly?
Have you checked your intank fuel filter?
Have you verified the lift pump is working in tank?
Have you done a smoke test on the car like other suggested above?
Have you pulled your valve cover off an inspected the cam lobes?
Have you done a compression test/leak down test?'
Have you tried a good used/new DME?



When you installed the new sparkplugs did you verify the correct spark plug gap?
When you installed your AFM did you make sure it was the exact same part number? as different years and models are COMPLETELY differently tuned AFMS and will not play nicely with the DME

The m30 has nothing special to it. She's a good simple engine you can figure this one out yourself. But i think you should ask yourself if you've really put your efforts where they are needed to figure out whats really going on with this car.

Every post you've sent us has been about some item that you've replaced and nothing about actual diagnostic information that would allow any one to provide proper input for you back.

I have actually done a lot of diagnosing, and everything that I've replaced was only due to the fact that they were all out of spec. Every item I've replaced needed to be replaced. I just tackled the fuel tank yesterday and the inside is completely clean and the pump works perfect. The afm I purchased from auto zone is a reman, and it is horrible. I sourced a known working one from my dad's old 535is and it didn't solve much. Icv is also guaranteed to work. I checked all vacuum lines yesterday and they all seemed perfect and I put my finger to the fpr vacuum line and it was very strong.

[Aviveiros27]

I also haven't done a compression test because it is more of an intermittent issue. So it leads me to believe it's electrical. I have yet to source a good ecu. I don't want to purchase a $70 one off ebay that doesn't work. Does anyone have a 179 ECU ?

[Kinetik]

was the 535is a 88/89 because the AFM will only work on a 88/89 car sinceyours is a 179 ecu

- - - Updated - - -

Is your car a stick or an auto i have 2 179 ecus.

[Aviveiros27]

was the 535is a 88/89 because the AFM will only work on a 88/89 car sinceyours is a 179 ecu

- - - Updated - - -

Is your car a stick or an auto i have 2 179 ecus.

Mine is an auto. And I believe the 535 is an 88.

[Aviveiros27]

I stand corrected. It is an 87. That would explain why it didn't do much.

[Kinetik]

Differences between motronic 1.1 and 1.3 your car is a 1.3
https://www.bimmerforums.com/forum/showthread.php?1430281-Bosch-Motronic-1-1-1-3-BMW (https://www.bimmerforums.com/forum/showthread.php?1430281-Bosch-Motronic-1-1-1-3-BMW)

ECU compatibility list
http://www.bigcoupe.com/phpBB2/viewtopic.php?t=646

[Aviveiros27]

Differences between motronic 1.1 and 1.3 your car is a 1.3
https://www.bimmerforums.com/forum/showthread.php?1430281-Bosch-Motronic-1-1-1-3-BMW (https://www.bimmerforums.com/forum/showthread.php?1430281-Bosch-Motronic-1-1-1-3-BMW)

ECU compatibility list
http://www.bigcoupe.com/phpBB2/viewtopic.php?t=646

I can't believe I haven't asked until now but is there a way to get fault codes out of this car?

[Kinetik]

I can't believe I haven't asked until now but is there a way to get fault codes out of this car?

179 ECU Supports stomp test codes.

https://www.sssquid.com/v3/bmw-stomp-test/

[Aviveiros27]

179 ECU Supports stomp test codes.

https://www.sssquid.com/v3/bmw-stomp-test/

I just tried and only got the basic code 1444. But I've also had the battery unplugged for a day so no codes should be stored. How long does it usually take for a code to reappear?

[Aviveiros27]

update: I drove the car around for a little bit (if you would even consider stalling about 5 times driving) and redid the stomp test. I got 1222 l, being the lamda 1 code. Is that the o2 sensor?

[shogun]

1222 - Lambda control fault code is produced when Motronic system in Bosch control unit receives signal indicating that air/fuel mixture is either excessively rich or excessively lean for period of time longer then 10 seconds. Majority of the causes that affect drivability of the car can be responsible for DME flashing this error:
•air leak
•defective Air Flow Meter ( AFM)
•bad engine temperature sensor
•incorrect fuel pressure
•problem with injector(s)
•defective evaporation system
•empty gas tank
•issue with spark plugs
•problem with valves
•etc.

https://web.archive.org/web/20080203032830/http://e30world.com/fuel/BMW-E30-DME-Motronic-fault-codes

1211 - DME, Motronic computer, related fault - which may indicate problem with car computer itself. Delete any stored codes and perform following test: Start the car and let it run for 30 seconds; Turn off car and let it sit for another 30 seconds; Perform diagnostic test again; If the same flash code re-appears DME should be replaced

1215 - Indicates problem relating to Air / Mass Flow Meter - AFM or MAF depending on your e30 model. Causes could be cable wire damage, short circuit in the unit, or air / vacuum leak (check air intake hose - big L-shaped one)

1216 - Designates error with potentiometer in Throttle Position sensor. Some later model cars have potentiometer, as opposed to switch (TPS) found on majority of e30 s. This code will be active if inappropriate sensor values are read by control unit, and although presence of this fault code may indicate bad potentiometer, wire harness connection at the sensor is common issue (corroded, loose connection, or broken).

1221 - Fault related to Oxygen ( O2 ) sensor is present if the sensor is unplugged, bad / not-operational, or sensor values are out of range. Test the O2 sensor for proper operation, as well as check harness connections by the sensor and by the battery tray in the engine compartment.

1222 - Lambda control fault code is produced when Motronic system in Bosch control unit receives signal indicating that air/fuel mixture is either excessively rich or excessively lean for period of time loner then 10 seconds. Majority of the causes that affect drivability of the car can be responsible for DME flashing this error: •air leak
•defective Air Flow Meter ( AFM)
•bad engine temperature sensor
•incorrect fuel pressure
•problem with injector(s)
•defective evaporation system
•empty gas tank
•issue with spark plugs
•problem with valves
•etc.


1223 - This fault code indicates problem relating to Coolant Temperature Sensor (CTS). Test the CTS sensor for proper functionality and check sensor wiring and connections.

1224 - Fault with Air Temperature Sensor , which can indicate bad sensor, break or short in wires

1231 - Battery Voltage / DME Main Relay error code can mean that battery voltage is out of range (either too high or too low), or that battery was disconnected. Test charging system and /or battery to find problem cause.

1232 - Error associated with "idle" portion of Throttle Position Switch. Test TPS for proper operation

1233 - Error associated with "WOT" (Wide Open Throttle) portion of Throttle Position Switch. Test TPS for proper operation

1251 - Fuel Injectors (group #1) fault can indicate problem with either individual injector or first group of injectors. Solution is to check fuel injector connectors, wiring from DME to injectors, and to test injector(s) for proper spray pattern. Additionally, fault code 1283 could be set in conjunction with this one.

1252 - Same as 1251

1261 - Fuel Pump Relay Control code indicates break or short circuit associated with fuel pump relay. Test for proper signal on number 3 pin on DME. It can also mean that output stage of DME is faulty (Motronic version 1.3 only)

1262 - Possible causes for Idle Speed Control fault are:•damaged wiring to the idle speed actuator
•wire from DME is defective
•output stage of DME is damaged
Also if engine stalls while it is above 600 RPM, code 1262 will be set

1263 - Purge Valve fault can indicate that Evaporative Control Valve is faulty, that wire from DME to the valve is damaged, or problem with output stage of DME (Motronic version 1.3 only)

1264 - EGO Heater error code is stored if there is fault with Oxygen Sensor Heather or it's relay , Air Pump relay, supply wiring, or wire from DME

1444 - No errors

there are vacuum hoses below the intake, at least on the M30 E32, see pic here https://www.bimmerforums.com/forum/showthread.php?2399873-High-surging-idle&highlight=intake

[DesktopDave]

1222 is the code from hell on early Motronics. It indicates that the readings from the O2 sensor are out of range, but the number of causes is large. Usually the O2 sensor is working, the problem is somewhere else. Shogun's list is a great place to start, but that's a lot of ground to cover.

I'd be tempted to beg/borrow/steal a wideband O2 sensor with a functional emulated narrowband output. I have an AEM like this one (https://www.amazon.com/AEM-30-4110-UEGO-Ratio-Gauge/dp/B00N3VGPYS) on my E24 to track down a lean running problem. It really helps with diagnosing problems since I get instant feedback from every change I make. I had a lean idle problem last year I haven't figured out yet.

[shogun]

Make a smoke test like this https://www.youtube.com/watch?v=AsgB9eBl58I

[RSheiman]

I just sent you a PM

[Aviveiros27]

I just unpugged the o2 sensor and the idle smoothed out a bit but it's still jumpy and it stalls.

[Aviveiros27]

I just sent you a PM

Rplied

[Aviveiros27]

Is there a way to do a continuity test on every pin on the ecu? Any links?

[Aviveiros27]

I did a test at the ecu plug. All grounds checked in good. Main power to the ecu was good at 12v relay powe was good for main and fuel. The only thing that stuck out to me was the reading for open throttle and closed throttle; the voltage never changes??? I also have a question about the kick down. Does the kick down send voltage when it is pressed or does it cut off voltage when it is pressed. Because at idle throttle position, there is a constant 12v from the kick down switch output?

[DesktopDave]

You have the electrical troubleshooting manual, right? If not, here's the link (http://http://wedophones.com/Manuals/BMW/1989%20BMW%20635csi%20-%20Electrical%20Troubleshooting%20Manual.pdf) for the '89 635CSi. Every time I get another project car, I download the appropriate ETM and leave a printed copy with the car. That ETM is worth its weight in Danegeld!

Section 2460-2 has a diagram of the kick-down switch. Should have a single gray/yellow wire, grounds pin 2 of the Motronic. There's a whole section in 2640 with testing, troubleshooting & description info.

[Aviveiros27]

I'm starting to realize simple questions I should've asked way earlier. Does the 89 635csi have one fuel pump or 2 fuel pumps. Because I'm not exactly sure if the intank one actually works.

[Aviveiros27]

Update if anyone cares: replaced ecu with one off ebay and smacked the cat a thousand times with a hammer and the car seems fine now. Still not perfect at cold start but once running it's good.

[DesktopDave]

That's progress! Glad you didn't give up on it.

[slofut]

Give us some actual numbers. What is your fuel pressure at idle, what is is under load and driving, and what is it when you switch off the car. And yes, the car will barely run without the in tank pre-pump working. If it's running but you haven't pulled it out and visually inspected the sock, the pressure hose and the connections you can't make an assessment of it's condition. This is very likely your culprit. My 88 now has a single hi pressure in tank pump and never been better.

[Aviveiros27]

Give us some actual numbers. What is your fuel pressure at idle, what is is under load and driving, and what is it when you switch off the car. And yes, the car will barely run without the in tank pre-pump working. If it's running but you haven't pulled it out and visually inspected the sock, the pressure hose and the connections you can't make an assessment of it's condition. This is very likely your culprit. My 88 now has a single hi pressure in tank pump and never been better.

Issue was solved
ECU