Alright R3V. Im 80% stumped. (Now 90%) New development

[LJ851]

Short in wiring(or elsewhere) causing that batch of injectors to stay permanently on.

[matt0300]

Broken rocker?

[Ryann]

Just to clarify guys, your harness issues resulted in a lack of fuel delivery through injectors 2,4, and 6?

Based on the symptoms it's looking like either excessive fuel from injectors 2,4, and 6 or somehow incorrect spark timing for the same holes. The dead holes have spark and fuel as well as compression!

[Wishno87]

Check your timing. Could be off by a tooth.


If not the timing or the C191, get a new harness entirely. Theres no reason why bank 2,4,6 shouldn't fire especially if that's the order the DME sends the signal.

So to check the timing you mean to take the timing covers off and make sure the marks are in the right places right? Been a while since I have had to do this to a m20 so I sorta forgot.

[Wishno87]

what exactly did you do? I actually replaced the pins and sockets in the c191 connector in order for it to work again. You have to special order those little pins and sockets, so im assuming that's not what you did?

I have a 90 325i that I have been swapping parts from. The 90 is in running order other than a blown headgasket. Were your pins damaged by corrosion?

[gtdragon980]

what exactly did you do? I actually replaced the pins and sockets in the c191 connector in order for it to work again. You have to special order those little pins and sockets, so im assuming that's not what you did?

[lolcantturn]

Check your timing. Could be off by a tooth.


If not the timing or the C191, get a new harness entirely. Theres no reason why bank 2,4,6 shouldn't fire especially if that's the order the DME sends the signal.

[Wishno87]

Thanks. Ya I figured out how to pull it out. The lock ring is underneath where you cant see it and I have never worked on a late model so I was kind of lost for a second. Any other ideas for diagnosis guys?

[ForcedFirebird]

The connector comes out the same way the round diagnostic connector does. One you unscrew the 2 halves, there's a "nut" that sandwiches the steel pce.

[Wishno87]

Did injector harness. Still nothing. Going to do CPS and im just about done. Not really much left. Still running on only 1,3,5.

[Wishno87]

How do I take that harness out of the ring holder thing? Never had a late model before so im a little lost. I screwed off the C191 connector but I need to remove the injector side of the harness from the mount thing.

[Wishno87]

Good! About to get started right now. Luckily i have a 90 325i that I have been swapping parts between the whole time.

[gtdragon980]

agreed on the c191, sounds exactly like my problem i had.

[Wishno87]

Awesome! That stuff is a pain to get to but at least its a lead. Thanks!

[lolcantturn]

^The car broke while going down the road. Unless there's an evil squirrel living under the hood..

Yep sounds like C191.

If you look through my M20 threads, theres this long complicated one in which I basically did EVERYTHING except the C191. Before the motor completely stopped working, it was running on 3 cylinders and really hard to start. It happened while I was driving. I basically did everything, every sensor, every injector, 3 ECUs, swapped the head, nothing. It was my C191, and it had exactly the same problem as you, I could pull the plugs from cylinder 2 4 and 6 and the car would run the same.

Rewire that C191 or just get another harness.