Need Help - Somewhat Functioning Turbo Car

[ty20404]

This is a little long winded but I need some of the turbo Guru's to read through this... Jordan, John and myself have been trying to figure this out for months.

Some of you may remember I blew up my old motor running too much boost about a year and a half ago. I had a new S52 block built at CES with Eagle Rods, JE pistons, O-ringed block, etc. I had the car dyno-tuned at CES by Jordan (RK Tunes), remotely and everything was copacetic... Car laid down 513 to the rear wheels at about 17 psi on 93 octane. As soon as I drove the car away it started acting up with a lean idle. But it was only occasional... Only randomly would the car lean out at idle.

I looked and looked and looked, nothing was out of line. By this time I had realized that I was even a little rich in boost. Not overly so, but 10.0 by the time I was over 5k RPM. I even had the car boost leak checked at National Speed (very reputable turbo build shop) and they couldn't find anything. Eventually after looking through everything and speaking with John @ CES, it looked like I just needed a little fuel at idle. Jordan sent me two new revisions, which we decided on one that helped with my lean idle. Oddly enough, occasionally the car would still lean out on idle.

Today I was in high boost setting and decided to pull a little and did so up to about 6k rpm, and as soon as I let off, the car wouldn't come out of 10.0 AFRs... I limped the car another 2-3 miles to my shop without getting into the throttle. When i would let off it would lean out to about 14.5-15, but that's it. Once I got to the shop I let the car sit and it would idle around 12 and then start dropping then stall. I did this two times to see what the parameters were doing and obviously the vacuum would drop right before the car stalled out.

I pulled some stuff apart, boost leak checked from the maf to the cylinder head, nothing... Boost leak checked from the filter to the cylinder head, nothing... Was taking over 30 seconds to leak down from 10-0 psi from the filter location. Could hear the air leaking through the rings and out of the valve cover and nowhere else.

Replaced the IAC valve with no change as well as the crankshaft position sensor. The funny thing I noticed was that when I had the car running after the CPS replacement, I didn't have the mechanical fan in, so when I kicked on the electric fan, the AFRs rose dramatically.

So I swapped out the battery with one that had higher CCAs and since it didn't have enough charge to turn the car over (barely) I Jumped it with my E90. Once I had the car running Jumpered to the E90 my AFRs were dead steady at 12.5 which is lower and steadier than it has been at idle since January... But whenever the efan would kick on the AFR would rise dramatically, to like the 17s/18s.

This was even with a newer revision from Jordan with more fuel at idle. Please tell me something here stands out as obvious to someone. Please ask questions if you need more details... I'm losing my mind over this.

Is my alternator shot and the reason I haven't been able to sleep at night for the last two months that I've been chasing this ghost in my car?

[geargrinder]

half-way through your TL;DR (jk, totally fine...) I wanted to know about fuel pressure, then I got to the voltage thing. interesting story, I suspect you've solved your own problem.

still would kinda want to know if your FPR + FP is all hunky and dory. unfortunately full load FP testing is a PITA unless you have a dyno (although I've seen gauges strapped to the windshield and celll phones strapped under hood and all kinds of hacks to work around it...), however since you have idle weirdness, that might still show up, so I might toss a gauge on it since it's relatively easy to check... but....

agree for sure seems like maybe you have a VR problem. sounds like your alternator is making juice but maybe the voltage reg is erratic. low (or even high) volts could have all kinds of collateral issues from MAF and other sensor reference voltages to fuel pump delivery etc. super easy to wire up a voltmeter into the cabin and take it for a spin and see what your system voltage does.

[Def]

It does sound electrical related if that fans make that big of a difference.



I would say that this is a situation where a standalone makes troubleshooting stupid easy. You just log what's going on, then look at the logs and it'll likely be staring you straight in the face.

[ty20404]

So I swapped the alternator to a larger one that was pulled from my old 328 and it made a huge difference. I'm no longer pegging 10.0 in boost and AFR at idle with my v7 tune was much steadier at about 12.7. Drove the car about 10 miles after that and everything felt great (even happened to come across a gen 1 viper to play with). This morning I switched back over to v5 tune which is what I left CES with and AFR at idle is back up to about 14.5. I still get a few moments of AFRs in the 15s but it has settled every time. The AFR at idle isn't quite as steady as I would like, but I'm going to continue to monitor. Also going to check all of my power cables from alternator to starter to distribution post to battery for like the 6000th time.

Also just in case anyone was curious, V7 was a revision of V6 that Jordan had done, we had tested V6 at CES but went with V5 since V6 got a little leaner at top end than John liked. So for all intents and purposes the difference between V5 and V7 at idle was just some added fuel on V7.

[rajicase]

Sounds fixed to me man. AFRs in 14s at idle sounds perfect. AFRs won't ever be perfectly steady at idle. Sounds like your idle is normal to me.

[GT35Rm3]

Glad you got it fixed. Need a ride soon.

[ty20404]

Well for some reason it started idling a little lean again today... Going to swing by AutoZone and have them do the battery test and see if the battery is okay. Anything other than idle is still normal though, again, not pegging 10.0. So my problem could have been a combination of alternator and battery. I will check the battery out and keep an eye on it and keep you guys updated.

- - - Updated - - -

Glad you got it fixed. Need a ride soon.

Bring your ass back down to Wilmington... Bring Sean back with you so we can do a Red Dogs reunion, lol.

[somebody5788]

If it indeed was a power issue before and it didn't just disappear for a while then I would clean all the power and ground connections thoroughly.

[ty20404]

Here's a video I just took of my issues that I'm having... Auto zone test showed bad battery on the first try and good battery on the second try.

http://s20.photobucket.com/user/ty20...ilc2l.mp4.html

[E36 HateR]

The reason your afr changes when your fan kicks on is because your bov is open at idle, disrupting maf voltage.

[ty20404]

I was under the understanding that the Tial is supposed to be closed at idle. John at CES installed this to get rid of the finicky Synapse that I had in there before. And why does the fan kicking on have anything to do with the BOV. I can understand the change in voltage due to load on the system. Not saying you're wrong, just need some more explanation.

[E36 HateR]

The synapse is the worst violator, but when the engine is cold the bov may be closed, after it gets hot it will pull muxh more vac at idle amd under decel, the fans on in the engine bay distrupt the air that is being sucked from the bov and depending on how close the maf is to the bov it will mess with the voltage.

Also your positive you have the right temp sensors plugged in on your manifold? I had the air temp sensor switched with the coolant temp sensor one time and it was funky.

[ty20404]

I will check plugs on sensors, but the BOV is literally 3 inches from the IC outlet. The BOV is just to the right of the radiator when looking at the front of the car. How should I test of its the BOV? Pull the vacuum hose from it and plug the manifold? Obviously don't get into boost heavy....

- - - Updated - - -

Sensors are all plugged in properly according to the labels that have been on the cables from the previous owner. It did run properly when purchased. I tried idling with the BOV disconnected and hole in manifold plugged but it was the same thing. The BOV is easily 2+ feet ahead of the MAF. I don't think John at CES would have set me up to fail on that install. As for the issue, it happens every time with the fan on but it does happen without the fan which leads me to believe that it isn't the air being disrupted at the BOV.

[E36 HateR]

Okay, im only stating an issue I have seen in the past, yours is different no doubt.

[ty20404]

thru my troubleshooting I had lean idle, so I jumped my e90 to the e36 and the AFRs dropped to 13.5. I did this on and off like 3 times and every time I would disconnect the AFRs would instantly go up. So I figured it was the battery and went and bought a brand new duralast gold (800 CCA). Still the same exact lean idle but now when I jump it with the e90, nothing happens. It still continues idling lean as hell. Wtf is going on with this thing?

[GT35Rm3]

Have you recorded maf voltage during the issue? Can you easily swap Ecu's?

[ty20404]

I'm running OBD1 Luke. Not sure if I can record MAF voltage...? I have a couple other DMEs here but not sure what the criteria is to swap it.

[geargrinder]

If it indeed was a power issue before and it didn't just disappear for a while then I would clean all the power and ground connections thoroughly.

This is good advice.

Also:

HOOK UP A VOLTMETER AND CHECK VOLTAGE while running and observing symptoms if that seems to be the issue! Super easy! Not complicated and would give more data points for this voltage / alternator hypothesis. Continuing to thrash around asking for more help and trying other stuff seems silly without taking the simplest of measurements.

"BOV's suck" dialog I am supportive of but seems irrelevant when fairly conclusively it seems some kind of electrical situation is happening and repeatable.

[ty20404]

I did this already. I was getting 14.2 Volts pretty steady with good AFR and bad. With the car off I'm getting 12.5 on the old battery. I would assume the new one is just as good but can check tomorrow. I also ohmed out a few points in the engine bay, specifically the grounding straps on the cool packs to the jump ground next to the diagnostic port and the ground wire at the end of the fuel injector harness. All were 1 ohm or less. I would think this would be satisfactory but maybe someone else can tell me otherwise.

I also cleaned the battery terminals and checked for a tight connection at the starter (to the best of my ability), the distribution block near the DME and the grounding strap from battery to frame rail. Nothing looked off even in the slightest.

[flyfishvt]

Just a shot in the dark here but it might not be a power issue. It might be a ground issue. Get a thick piece of wire and run a separate ground from the eyelet next to the vanos solenoid over to one of the strut tower bolts or just use a jumper cable to test it. I've had problems that I traced back to my turbo motor mount bracket. It's painted so it was not supplying a consistent clean contact between the bracket and the block.

[ty20404]

I half assed this last night as well. Used an 8 gauge amplifier wire from the eyelet to the jumper ground next to the diagnostic port. I will actually tighten the wire down like you said with the bolts. I had suspected that the ground may be the issue before but everything I've done to try to eliminate any grounding issues has come up empty handed.

I work with complex robotic tooling for inspections in hazardous environments so the electrical stuff isn't new to me, in fact I've been dealing with some noise interference issues on some recent projects which is why I've been checking resistances as well as voltages.

I may switch back to my old alternator to see what kind of changes in behavior there are.

Two other things that I will point out which may have some impact on this topic is my fuel pump wiring and the DME harness. The fuel pump has a separate harness/relay that is run off of the battery but every time I've checked voltage there everything is as it should be. The DME harness has a white pass they connector spliced into the 6 wires for the coil packs. It appears as though maybe there was some sort of stand alone booster for the INJECTORS installed at one point.

- - - Updated - - -

20160624_203217.jpg

This is a picture of the inline connector.

[geargrinder]

hmmm. so much deja vu, had a similar extra-ground-jumper required for my old Audi build however that was about misfires not about AFR's.
relaying FP w dedicated short fat wires from the battery is always great idea for big power car. relays don't tend to fail in partial-low-current mode like that but I suppose you could toss a new one in... usually it's just the bog standard type relay...

[ty20404]

hmmm. so much deja vu, had a similar extra-ground-jumper required for my old Audi build however that was about misfires not about AFR's.
relaying FP w dedicated short fat wires from the battery is always great idea for big power car. relays don't tend to fail in partial-low-current mode like that but I suppose you could toss a new one in... usually it's just the bog standard type relay...

I will do some more diagnostic on the relay for the Fuel Pump. Check voltages and swap a like-for-like relay in to see if that makes a difference.

[ty20404]

Swapped relays, checked voltage at the relay, which was good at 14.2. Swapped in two other relays to make sure that wasn't it and no change. Did all of the ground connections with not only an 8 gauge cable but also jumper cables. I pulled the valve cover to make sure everything with the VANOS was okay which it was. I pulled the plug on the TPS, VANOS solenoid and Cam Position Sensors individually with no change in AFRs or the rough idle. I removed the plug harness on the injector wires and soldered the wires back together. I cleaned the MAF as well with no change. I swapped back to V7 on the tune and took the car for a spin. It was idling high in AFR when I returned so I flipped on the AC, which bumped up the RPMs and brought the AFRs back down. I let the AC run for a few minutes then flipped it off. The AFRs then came down to 13ish and stayed there for about 5 minutes. This was the first time since the battery swap that the AFR at idle had been "normal". After about 5 minutes of good AFR and smooth idle, I flipped on the e-fan and of course the AFRs shot up. Anyone have any other suggestions to check out?

i think my next course of action would be to ohm out the engine harness to all sensor connectors to make sure I don't have a short or that all of the connectors are labeled properly and connected to the proper sensor.

[geargrinder]

When you say you monitored voltage before, did you mean while driving under load? Really seems your alternator or VR are still just not keeping up under load and/or when hot. Ideally I'd do a good drive test, trying all the things you just describe (AC on/off, efan on/off) w/ the voltmeter on the dash so you can see it while you're watching the wideband at same time. If you see system volts dropping at low idle and when hot and/or under excessive load etc. then you know you still have some charging system problem.