Need help badly M20

[mzollo]

****EDIT**** please read symptoms on page 2!!,
Okay R3v ive come here in a time of mass confusion and frustration.. So here is a little history. I picked up this 87 325 about a year ago its my first e30 and i love it. Its originally a Lachs e but had a 2.7i swap about 5 years ago. So now onto my issue...Back in november i had this problem develop, as I was driving the car it would randomly die. As in flatline across all six causing you to jerk forward while driving, but this would only occur for a split second all would be normal as soon as it dies it goes right back. So i figured CPS replaced it with one that Ohmed out correct. No avail. Now this is what makes it a Pain, its ridiculously inconsistent. I went back to school and didn't take it with me. Came back home and it drove great until a few days ago the problems would happen every few days or so never under the same circumstances.

Other info: Idle voltage 13.3/4 running 13.7/8. Not RPM dependent. Rain seems to make it worse. No hesitation, just dies. No loss of power. Gas mileage decreased days it acts up

Parts Replaced
-AFM known good
-CPS ohmed out fine
-DME 173 known working
-FPR Known working
-spark plugs (new)
-Wires
-Coil Pack known good

So this is where I'm at i really just want it back on the road so i can enjoy it. If anyone has any ideas please let me know, im attaching a video of it at idle this morning. This is all the information i have gathered and i hope someone can help me here.

*****EDIT***** new symptoms car dies after 20 seconds dies if you blip throttle blows white smoke. GO! page 2 for videos

[mzollo]

Waiting on video to process

[mzollo]

[FLG]

Did you clean all your grounds? Also clean and inspect the connector next to the fuse box. Has the same loss of power /jerking issues turns out that connector was corroded some.

Sent from my Galaxy Nexus using Tapatalk 2

[mzollo]

I have not cleaned any grounds what would you recomend? They all seem to be intact though. And ill go give that a shot now

[jlevie]

When an event occurs, does the tachometer or econometer react? If the tachometer needle takes a big drop the DME is loosing power, ground, or timing data from the CPS.

I don't see new main and fuel relays in the list of new parts, so replace those. Also check the DME ground and power connections in the engine bay and check the fusible link in the small battery wire.

An ohms test of a CPS will tell if it open or shorted, but not whether is is working properly. For that you have to look at the signal with an oscilloscope. This being a used sensor, replace it with a new OE part.

If the tachometer doesn't react but the econometer drives toward zero there's a problem with fuel delivery or injector connections. Most of the time a problem with fuel delivery (bad pump, pump power) is more of a sputter than a cut. But an interruption in injector power or control can produce a cut. If the engine harness was made from 9/87 on, C191 below the intake manifold can be a problem. Check the pins and wires for corrosion.

While not as common as the other causes, the engine harness could be bad. Before changing the harness you should do more diagnostic work to make sure that the DME, coil, and injectors aren't loosing power.

[mzollo]

does the tachometer or econometer react

the Econo-gauge does react But* it is not connected to anything.

C191 below the intake manifold can be a problem

I'll check those and hit it with some contact cleaner.

make sure that the DME, coil, and injectors aren't loosing power

How can i check to see if they are loosing power?
and thank you ill be diagnosing all afternoon

[jlevie]

The easiest way to check for loss of power to something is to use an LED test light. An incandescent test light isn't as good as it may not show a brief power interruption.

[mzollo]

WTF? pull the boot off the bottom of C191 and its filled with green coolant?

[mzollo]

WOO! progress i took the Boot off and every time i touch the wires underthere if my fingers are wet it shorts im guessing and the engine dies.

[mzollo]

Maybe jumped the gun it dies regardless of if i touch the wires but i think this might be the culprit.

[dustyperez]

mine had a similar issue and there is a plug under the dash on the left side that controls the relays. wiggle some wires under there if you didnt get it fixed. i think maybe it was green??

mine was just loose plugged it all the way in and perfect

[mzollo]

So here is where im at i repaired the C191 plug and the car will idle for 10-20 seconds then die abruptly. i can get the car to run for a good amount of time if i keep my foot on the gas and as soon as i let off it dies. signs of a bad fuel pump?

[jlevie]

Could be a bad pump or FPR, check the rail fuel pressure.

[Kozworth]

How did you repair the c191? My friend had one where we cleaned the pins and lubed it with dielectric grease, and no changes. It turns out, on the female connector, the wires to the female pins were not even connected, some dangling on.

There is a diy of cuttuing the whole harness out, soldering custom male female individual prongs, and then calling it a day. One of the wires on the male side of the harness (I think) goes to literally nothing just as a heads up.