E32 750iA wont start - fixed

[DavidQ4]

Hello guys!,

I bought last week a nice (I will upload pics soon) 750iA from 1988.

Engine had problem with one fuel pump. I was reading a lot of info on the forum for know more about this engine. Monster engine...

I was testing somethings last days, I install a Y connection on the fuel pumps pipes (using one witch one was working) for send fuel to both engine sides.

It work, but I made a mistake and dont put the pipes good and a lot of fuel was leak on the trunk.

I disconnect battery after check this lot of fuel leaked and clear the fuel from trunk.

Put again the battery, but now my EML light is always OFF, and engine turn, start, and instant died.

If I remove the fuel pumps relay, engine crank but dont start. If I reconnect its, I can hear the noise of fuel pump and I try to start the car again, engine start and died.

I get message CHECK CONTROL (If Im not wrong) on dashboard message panel.

I exchange MAIN RELAY I with MAIN RELAY II, but no difference.

Still no EML light ON (never) and engine died instantly after engine start.

My car is EU, so I cannot test STOMB TEST. And I dont have the pelican test, and I cant put my car on a garage for repair.

I remove the Y on fue fuel exit from pump, and try to exchange fuel pump relays (no difference) too, but no difference.

I check the fuse links A and B using your tutorial, and both are OK.

Where I can start for checking the problem?

I try to jump the E32 using another car with wires but still the same, so .... battery is not the problem?

Tomorrow I will try to check voltage on fuel pump connector, but I can hear both working when go to ignition key position.

Sorry for my english, I'm from Spain and my english is not good as I wish .

All help will be welcome here.

Thanks you.

[shogun]

which model? E32 or E38? Because one time you say E32 and then 1998. If E32 1988:

You have to check first if the one fuel pump is really supplying enough pressure and volume to the engine, here a test http://bmwe32.masscom.net/sean750/fu...Regulators.htm
Also, on top of the tank there are 3 connections, 2 are for the fuel pumps feed line, the one more in the middle is the fuel return line from the engine to the tank. When you did the y-piece, did you connect one of the outer pipes with the other?
http://bmwe32.masscom.net/sean750/fu...t/Fuelpump.htm

That the EML light never goes on is strange, it could be a problem inside the cluster http://bmwe32.masscom.net/johan/eml_bulb/eml_bulb.html
Test once more inside the e-box if there is >13.7V power, just to make sure that the fusible link which goes to the e-box is fine, sometimes it has small haircracks difficult to find. That is this fusible link shown in the first 2 pics
http://www.bimmerboard.com/forums/posts/377728/
wiring diagrams are here http://shark.armchair.mb.ca/~dave/BMW/e32/

I would first fix the fuel problem, fuel supply, volume, pressure.

[DavidQ4]

Sorry a mistake with keyboard.

My car is E32 1988 sorry.

[DavidQ4]

Thanks for your fast response.

You made always an incredible job here.

I install the Y on the top the one of the two up pipes of this pic:

Attachment 644868

Only one of these (upper) had fuel preassure, my car was running on 6 cylinders, so I install the Y and finally get the 12 cylinders runing.

But going up of a little climb, car start to fail, fuel gauge was just enter on reserve, and engine start to lose all power.

I check the Y connection thinking about this was the problem, no enough fuel preassure to both engine sides, so I remove it, and install again as normal the two both pipes.

But still the problem, so I add some extra fuel. And the engine runs again, move the car 50 meters, then I dont put well one of fuel pipes so a lot of fuel was leak.

After I removed the battery and reconnect well the pipes, reconnect battery again, no more EML light was on again.

I experienced the same problem when removed first day I bought the car the K212 and K213 relays (Main Relay I and Main Relay II). Maybe I install on reverse mode and I broken something?. When removed one of them, the EML light dont go ON when ignition key or start, when reconnect these main relay, then EML light go ON when ignition key and goes off 2/3 seconds after engine start.

I was thinking about a problem of no enough fuel, and maybe the problem is easy to fix: no fuel because the leak, but not the same sympthons that I experienced last days when car has no fuel, car fails a lot, start, run about 3/4 seconds then push down accel and died. Now, car start, you can hear how it crank and engine goes off automatically.

I check both fuse links, I removed the black cover of Fuse link B, I inspect it with power light and I cannot saw nothing bad there, Also Fuse Link A was very good too.

PS. My best summary: engine fire but instant died. If I remove both fuel relays engine turn but dont start never. I will check tomorrow the fuel preassure using your link.

Thanks you

[shogun]

Check the fuel pressure, and also check once more the K212 and K213. Based on the exact date (month/year) of production the locations of main relay and fuel pump relays are in a different location, see here
http://www.e32-schrauber.de/bmw/s-relaisbelegung.htm
88 http://www.e32-schrauber.de/bmw/s-relaisbelegung.htm
1989 - 1994 http://www.e32-schrauber.de/bmw/date...8_88-07_94.pdf
But this is a US wiring diagram and yours is a EURO spec., so carefully check.
What is the VIN of the car? last 7 digits? You can check the production month and built year here https://www.mdecoder.com/

[DavidQ4]

Mine looks like it: (right relays are black and have the FUEL RELAY PUMP over)

http://www.e32-schrauber.de/bmw/date...8_88-07_94.pdf


My prod. Date is 1987-11-17

My fuel relays are on the total right, so, the center relays K212 and K213 based on the upper PDF are my engine control module relay. I assume you can exchange both without major problem... (really I was runing the car with both relay exchanged, like fuel pumps...).

I will try to get tomorrow from scrapping some relays for test and will add too more fuel to the tank. Maybe the problem is the most easy problem... because I think my pipes over the pump are not too hard to push with my hands so I think I dont have enough fuel pressure as yoou said...

Thanks you for your time. I will write tomorrow with new information.

The E32 750iA is one of my fav. cars

[DavidQ4]

Hello,

I have good and bad news.

After 5 hours working, i found this problem:

(First I will explain something about this car. I bought last recently to a good, "mechanic" working on BMW service. He said me he install complete tank with pumps from another 750iA because this pumps was broken because car was stopped 1 year.

This guy, said a common friend he was thinking on selling car, he dont have time to finish it.

I bought it with some problems, runing on 6 cylinders... erratic idle... etc.)

Well, Im ready to explain what I found today...

First of all, when I try to start the car, and hear the engine sounds, I hear like some water into engine, and some buzzing noise, and little vibration. With key removed.

Vibration come from throttle assembly, for sure.

And... I found one throttle assembly I can move with my hand and it go back to original position. The another one, not go back, its very hard to move.

I still listening sound like water into the engine... not from coolant, inside air intake...

So I remove the MAF and found some fuel rest and smell fuel...

I remove the pipes, and look into air intake after moving manually throttle body. Engine is totally flooded, maybe like 1 inch of fuel inside air intake. Its only on one engine side.

The problem what I see, is FUEL on the engine oil (because air intake had a pipe that goes to oil vapour pipe... so ¿a lot or a bit? of fuel go into the oil engine...

Well, how its possible having engine too flooded?

I remove the fuel pump, I dont touch internal pipes from fuel pumps to the tank exit... but I notice the old owner of my car, mechanic, install the pipes on wrong sides....

I check internet pictures of pipes from pump, and my car have it changed. Bad installation of pipes.

I solve this problem, disconnect al pipes on engine side, then install only 1 pump relay, ignition key, localice fuel exit from pump and looking on engine side.

Also, when I disconnect this throttle assembly electrical and put ignition key, EML goes ON again with ignition. But until I dont remove fuel from air intake, and change the filter and oil, I cannot try to start engine.

I hope it is not damaged.. Car only has run about 4 km with the wrong pipes installed (4 from the mechanic and me about 200 meters only...).

Well, sorry but I was working on the work 12 hours and another 4 hours with the car, I will upload pictures of all process.

Its terrible looking into air admision and check it filled of fuel... car was empty of fuel when I add 5 liters, then maybe 1 liter go out and 3 to the engine ... I removed the oil plug and there is oil with a bit of white sustance, surelly fuel mixed with oil.

Thanks you for all your help.

If anybody had some suggestion for cleaning engine will be great...

My next step:

1º). Find some used throttle assembly working
2º). Remove fuel from air intake
3º). Change oil filter and fuel filter

[shogun]

Throttle valve (DK) try to repair first, probably gunked up and the carbon brushes stuck, info on my website with testing data and here http://www.mwrench.com/Whitepapers/DKMotorcleanup.pdf
Even used DKs are expensive, there is one on Ebay Germany for EURO 299 plus shipping, search for: BMW E32 E31 M70 Drosselklappe Drosselklappenstutzen EML 1733024 0132010454
I have some M70 DKs on stock here in Japan, but they are quite heavy and I assume only shipping cost by airparcel will be around $50/piece, and shipping time to U.K. maybe 2 weeks, so check in Europe.

Change engine oil completely. You may have to change the oil and filter again after running for about a half hour to get the last of the contaminated oil out of the engine.
You may also have to change the 2 filters in the air intake box, or remove them and let them dry, that there is no more fuel inside.

Fuel filters are 2 for the M70, each pump has a separate fuel filter http://bmwe32.masscom.net/sean750/fu...eplacement.htm

[DavidQ4]

Thanks you shogun!

I was reading your post about DK cleaning and repairing.

Fuel go into engine from return fuel line and jumping into the fuel pressure regulator, and from it, the fuel travel to air intake.

The another bank is totally empty, so I assume I have one fuel pressure regulator working and another not working (or not working well), because one leave travel fuel and another one no.

Tomorrow I will upload the pic of inside air temp with fuel pool...

Now time to check DK.

I am very grateful

[DavidQ4]

Fresh Update!.

The problem is partially solved.

My EML light was always off, and the BMW 750iA E32 wont start.

One of both Fuel Pressure regulator (left side from the front of the car) was broken. Air intake was sucking a lot of fuel from it, continue, all time. You can assume the fuel must be fired on engine after enter again on air intake but.... there is a problem...! the Throttle Assembly dont work from this side, so engine had a lot of fuel (a pool...) and no air.

One of both Throttle Assembly (DK?) not work (left side from the front of the car). I remove, disarm, clean, put again, then reconnect again, but still no EML light when key ignition or start engine.

We put the car over the crane to move it to another street, and move the car 1 km (downclimb) and all the fuel on the air intake was out automatically .

We put the car on the floor again, then put the key again for check and... EML LIGHT GOES ON AGAIN!

So, the excessive fuel on air intake made it possible (NO EML LIGHT).

Remove oil and oil filter. Install new. Install al engine componentes again (MAF, Throttles, etc).

The car was hard to start, but the noise changed, and after 3 tries, it start (bad start, very bad, very poor, 500 rpm maybe... but after a minute engine start to work a bit better... so after 5 minutes the car looks 'great' but with very low power and some white exhaust and a bit black.

Well, the car runs with very low power, but runs.

We notice the AT fluid was close to empty.... so we add 1 extra litres of ATF Dextron III, and test the car... runs a lot better, stop again, add another liter, and the car runs like 1.6i and 1.500kg of weight.

I assume this is totally normal because the left bank is only getting air from pipe of fuel pressure regulator (it is removed, the pipe... so engine suck air from a very little hole).

Tomorrow I will remove a bit the screws of this DK, for create a major air intake.

Engine now sounds a lot better in comparision when I bought the car. If I reconnect the pipe from air intake to fuel pressure regulator, engine had again erratic idle and close to stop.... So, I will check tomorrow because today was a very long day... (im not mechanic, but I learn a lot on this forum with a lot of posts and yours responses, thats help a lot).

When push the accel a bit, you can notice how sometimes the spring of DK not move really good, start to move a bit but i think internally it dont move much...

And, I will need to check where the car have the leak of ATF fluid from transmission (is the same fluid for servotronic?)

Love this car, its a monster!

[shogun]

ATF for the 4HP22 is any DEXRON III or compatible. Power steering fluid on a 1988 750 was Pentosin CHF 7.1 mineral based, no longer available. Can be replaced - but not mixed - with synthetic Pentosin CHF 11S, or the equivalent to Pentosin CHF 7.1 from Febi Bilstein 06162 mineral based.
Febi Hydraulic fluid green 06162 >>>>>>>81 22 9 407 549 BMW (mineral) Equivalent of the discontinued Pentosin CHF 7.1
Febi: Hydraulic fluid (synthetic) green 06161 >>>>>>>>81 22 9 407 758 BMW, 82 11 1 468 041 BMW = CHF 11S Pentosin

[DavidQ4]

More EML problems...

I disconnect DK from 1-6 cylinders to test why car run very poor, and after 3 minutes, engine dies.

Another DK from 7-12 cylinders was making a noise (cli cli cli cli cliiiccc liclic lcilcilcilci), try to start again, but no more EML light ON again.

Remove battery, reconnect DK, connect battery again, but no EML light goes ON when put the key and the engine wont start.

Engine is not flooded, oil is OK. Put another good and new battery for testing, but still no EML light...

Today before testing DK, when stop engine, the DK valves was making some clicking noise, like they are trying to move a bit cliclicilcilcilcililcilililililcicccollliiiii and engine vibrate a bit because the DK vibrations.

Can be my EML defective?

I read a nice article with strange EML problem with wires cut, and another post with EML blower inside.

What can cause EML light never go ON when put the key on ignition?

A EML defective?

Yesterday the EML light come ON after clean the DK but I test it, and no EML goes ON at first time. Then remove DK again, the crane up the car, move the car a bit over the crane, then the crane put again the car on the floor, and when put the key again, the EML light goes ON again.

Maybe some bad wires or EML can be the reason why car don't start and EML light dont come ON on ignition.

[shogun]

Could be bad wires in engine bay between DK and e-box. Sometimes still have contact, sometimes not. Or between e-box and cluster. Also check if the 4 plugs are tightly fitting at the rear of the cluster.

[DavidQ4]

I have a read about your post and replies about fuse links.

I look, but dont checked it with polimeter. I will replace directly with typical fuse for music amplifier.

And I was reading this topic:

http://www.bimmerboard.com/forums/posts/236235

I never saw the OBC on, even when the car was with EML on on key ignition and the engine runing.

[shogun]

That is the hidden fuse for OBC and anti-theft, left side under rear seat base, sometimes difficult to see even when the seat bottom is lifted. Check that too.

Do you have a spare cluster to swop for a test? Maybe the cluster is the problem? http://bmwe32.masscom.net/johan/eml_bulb/eml_bulb.html

[DavidQ4]

I have checked again the fuse link, it appears to have a bit of some corrosion/humidity (only a little). I forgot the multimeter...

IMG_20190204_200154.jpg

I try with another EML module (original from this car, but old owner removed because was defective - he said some water was over there, surely when he had it removed on the garage - ).

I install it, and EML light goes on again with the key ignition, goes off after 2 seconds, then goes on.

I had crank sensor disconnect for testing, so, reconnect, try to make the reset with doors and key ignition procedure, but still the EML error. Car wont start. DK dont make buz sound, and I can move free with my hands (hard to move but free, no electrical resistance).

Remove battery, wait 20 minutes, install again the EML was on the car from some months ago, then no EML light.

I check for buz noise from DK, but nothing. No EML light never. But i remove the upper cover protection for wires of injectors and EML. Then I start to move some wires, nothing happens, But I disconnect the DK valve I have disarm last days and clean, and the another one DK start to make some buz sound.

Stop key ignition, remove this DK valve without buz noise, then install another from the old owner (he gave me today 1 EML and 1 DK valve, boths original from this car).

Put ignition again, and EML goes ON, after 2/3 seconds goes off, and finally still off. But car wont start, but sounds change a bit, so maybe Im out of fuel.

When I try to start the car, sometimes OIL SENSOR advice goes on on my dashboard. Car sounds like no fuel.... maybe my tank is empty again so tomorrow I will add some extra liters.

Summary:

1º) I think the fuse link B (above pictore) is defective.
2º) I think old DK valve from passenger side was defective.
3º) If not, maybe is the wires, defective status of the plastic cover of the wires.

Tomorrow more...! thanks you!

[DavidQ4]

Jumped the fuse link but still the same problem.

Now my DK buzz with ignition key.

I have fuel coming from fuel pumps (both).

I have spark, I remove one plug, put old spark and save this video:

https://www.youtube.com/watch?v=Xxp1Fwhd3vQ

I assume if my car is not starting injectors dont have pulse, not opening and not adding fuel inside engine.

Tomorrow I will use autostart spray for start the engine and I will use a little lamp to check if they come on with trying to start.

Is there any reason that can cut injector pulse?

Thanks and sorry, I'm not mechanic and Im not english so its a bit hard to understand somethings

[shogun]

it sound like it wants to start, but either not enough fuel or something on the electr. side. Did you already the crankshaft position sensors and the 2 cylinder identification sensors (donuts) ?
https://www.bimmerforums.com/forum/s...osition+sensor

[DavidQ4]

I think I understand now somethings....

When I bought the car, the first day the old owner send me a video, the car runs aparently "good" parked, he put N then accel a bit, it rev fast, but have some misfire, not too much, but it appears to be on cold engine.

Car run very short time period, he said me "the engine died when I was going to add some fuel...", he add some fuel, and I travel to watch the car and test drive. Car runs poor, like 6 cylinders but at least he start well. As more time was passing, the car was runing worst. Then finally, he was without fuel because all fuel go inside front right air intake and oil compartament, and the DK was filled with fuel then died finally and makes the EML light dissapear (inside short).

So, when I remove the DK valve, clean, and put again, the car lost most of fuel when it go up of the crane and go down again. I put the key ignition, then EML goes on again, after 2 seconds go down but go on again, signal of some problem in one DK valve (it was disconnect).

When I change the oil, install the DK valve cleaned, and engine start again with a bit of problems, because cylinders was flooded. After 5 minutes the car runs, not very well but runs. Move slowy, do not have too much power... but the reason was:

1º. Injectors are not working
2º. Engine was runing with some fuel inside air intake. When I remove again the DK valve, I saw some vapour of fired fuel inside the air intake.
3º. My DK valve was not working well, I unscrew bolts from DK when engine was runing, only a bit, for leave more air go inside admision, then engine died and DK start to make some bad noise. All fuel on air intake was fired when more air go inside the air intake when I leave DK semi unscrewed.
4º. My acutal EML is not right. It show EML then go off after 2 seconds. Not showing any EML error caused engine not opening injectors.
5º. Old EML that the old owner gave me, its working well, because it show EML light, then continue ON because he know there is some issue with some engine sensors. (Old owner replace because it was always ON the EML light...).

Car was runing while the (bad) fuel pressure regulator was installed on the car, it was add some fuel to cylinders like carburators engines.

I think Im right understanding the reasons why the car goes, and dont go some minutes after was runing.

Now, I need to check my injectors pulse, then replace EML with another one for testing it. Also, I will check what your are saying, Cylinders Identification and CPS sensors (tomorrow I will check).

Im trying to explain all things step by step because somebody can get the same fu**** issue and crazy problem.

Thanks you for all your help. I will share all info I can get tomorrow!.

PS. Car sounds like want to start, because when I put the key ignition, surelly EML was sending the test signal to injectors. Then add some fuel inside engine but injectors are stopped instantly from EML/DME.

[DavidQ4]

The guy who sold me the BMW, send too some pics with all hairness removed when he paint engine covers.

Maybe the error is only wrong CPS installed on wrong banks... I will check tomorrow for sure..... maybe this is the real problem

[DavidQ4]

From inside car, left bank CPS (driver side) had value of 455 ohm, and passenger side (right side) had a value of 495ohm.

I made a injector test light using trunk lamp, and i record this video:

I test the injector test light on both banks, same result:

https://www.youtube.com/watch?v=dreU0cJnWOc

So, If I had spark, I have injector pulse (i think this pulse is right...) and when I add some fuel on air intake the car start then died when fuel is off, my problem now must be fuel pumps, fuel filters, or both fuel pressure regulators (can be 2 bad fuel pressure regulators cause engine dont start?).

I test the pumps attaching a pipe tu the fuel exit and fill a lot of the bottle in very short time...

I need to buy a fuel gauge tester (T).

Im pretty sure now, car had bad installation of pipes over the pump. Surely the car had bad installation of pipes on the fuel pumps and return. Attached image of what Im thinkin its happens just now...


bombas.PNG

https://www.bimmerforums.com/forum/a...9&d=1549492650

[DavidQ4]

Won't start issue fixed!


Good morning!

Today at first time here, 07.00 am I go with the BMW and exchange the both fuel pipes over the fuel pump on the trunk.

At third try of starting, the car starts!

Now its already runing on 12 cylinders (or at least thats I think... I cant test too much because I need to go to my daily work). Car start very fast now (when I bought the car need 4/6 seconds to start..., I need to say I bought it with some failures, runing on 6 cylinders, no power, atf possible leak...).

Sounds change radically, now it can move and have power (before there is no power... ).

I will explain better al the symthoms, maybe somebody buy on the future a car like it, with exchanged fuel pipes (fuel pump line to the engine exchanged with fuel return line to the tank...), with bad DK valve (throttle body), with bad FPR creating a fuel pool on air intake, allowing the car runing without fuel pressure on the injectors - runing like strange carburator car...

When I install the Y pipe over the pump pipes, the car was without return sender, and I think the old owner install bad the pipes inside the fuel pumps pipes, but I check on internet inside the tank the pipes was right installed, from fuel pumps to the chasis of the pumps and the return pipe. But the problem was OVER the chasis of fuel pumps, into the trunk (this was where the fuel pipes was exchanged).

Now its time to check ATF leak, big leak, after 3 minutes of car runing, I can saw a lot of smoke coming from the side where dipstick ATF zone (surely ATF is going over exhaust and burning fast).

Thanks you very much, I will still updating with more information until car is repair.

[shogun]

Maybe it is not ATF leaking where the ATF dipstick is, but engine oil dropping from the engine valve cover onto the transmission/exhaust. Repair is on my website under top end overhaul.
ATF is usually red color.
In case it would be ATF, the usual leaking point is from the plastic strainer under the bell housing. the fault would then be a input shaft seal of the transmission.

[DavidQ4]

I read it, thanks you (your website is just incredible, thanks for all your work and your help).

I will try to take a look, unfortunately I dont have a place and tools for for making this job, but cannot be very expensive on a garaje (easy repair for a good mechanic with tools and safe place).

But this is not a problem because the car now start and runs very good, rev fast and work two banks.

Now start this leak, then pass spanish ITV (car annual inspection), then start the restore, minor problems, painting, etc.

[shogun]

If a garage has to do it, it will take 4-5 hours, when they are experienced with the M70 engine, but there are not many, which ever even have worked on an M70. You can DIY, not so many tools needed, just to replace the valve cover gaskets. This was once written by George Fontes and he sent it to me to include it in the shogun repair site. Someone copied this recently and uploaded it on youpublisher which coverts pdf documents into publications with flipping pages.
So now you can read all the 60 plus pages like a book. Plenty of good pics. This very informative guide demonstrates the entire process of removing and reinstalling your intake and valve cover gaskets.

http://www.youblisher.com/p/17534-M70-Topend-Refurbish/