Engine missing

[gtsfirefighter]

I've swapped a GTE into my 86.5. It starts and runs but has a bad miss. Here's a video. It has an open downpipe that's why it's so loud.I've searched some and think I know the problem, but I would like some other opinions.
Yes the CPS wiring is cracked badly on the cps side and the harness side.

http://s12.photobucket.com/albums/a227/gtsfirefighter/?action=view&current=enginemiss.flv

 

[jetjock]

CPS wires. Fix 'em...

 

[gtsfirefighter]

CPS wires. Fix 'em...

Thanks. Just needed some confirmation from someone with a clue.:icon_bigg

 

[jetjock]

It actually seems to idle pretty well considering. I don't think what you're hearing is a miss but until you fix the funky CPS you won't know for sure.

 

[gtsfirefighter]

It's hard to tell in the video but just giving it a little gas the motor feels rough and at idle is rocking back and forth. I've got another CPS with no cracked wiring, just not looking forward to replacing it.

A picture of the plug. I couldn't get the camera to focu any better, but the wires are bad at the base of the connectors and a little further down.

 

[jetjock]

I hear the off idle stumble but the idle itself seems OK. Hard to tell though. For it to die like that you must be losing the NE (Number of Engine revolutions) signal which the ECU uses to determine RPM. NE is one of the two main signals used to calculate basic injection duration and spark timing. It's the heartbeat of the EFI system.

 

[gtsfirefighter]

Would that explain why it would idle erratic sometimes? The rpms fluctuated quite a bit today but stayed around 6-700 rpms for the most part.

 

[bigaaron]

Did you report the missing engine to the police?

 

[jetjock]

^ rikita-boom!

Ken: Lots of things can cause erratic running, including the CPS, especially in a newly installed and/or rebuilt engine. My point was CPS signals are very important stuff and they need to be solid before looking for other causes. Basics first.

 

[gtsfirefighter]

Did you report the missing engine to the police?

That there was knee slapping funny!:biglaugh:

^ rikita-boom!

Ken: Lots of things can cause erratic running, including the CPS, especially in a newly installed and/or rebuilt engine. My point was CPS signals are very important stuff and they need to be solid before looking for other causes. Basics first.

I'll get that taken care of. Thanks

 

[BlackMKIII]

Did you report the missing engine to the police?

That was actually my first thought when I read the title. :biglaugh:

 

[gtsfirefighter]

I swapped the cps today and replaced the plug on the harness with one that had decent wiring. It started up but still has the miss to it. I've got some newer plug wires on the way (I think) so next up will be replacing those. The good news is that when I wiggle the cps wires around the car no longer dies, so I cure that problem.

 

[Quin]

Are your plugs ok?

 

[johnathan1]

Any error codes?

 

[Buddafucco]

Try pulling your injector plugs off 1 at a time with engine running. See if the miss stays the same when each is pulled off.

 

[gtsfirefighter]

Are your plugs ok?

They are brand new but I am going to recheck the gap when I put some new wires on.

Any error codes?

Nope, no check engine light and no codes showing on the supermonitor.

Try pulling your injector plugs off 1 at a time with engine running. See if the miss stays the same when each is pulled off.

That's something I was planning on doing after I check the plugs and wires. When I put the coilpacks, wires and plugs in, I was unaware of the wasted spark system so I don't have a clue if my wires are hooked up to the coilpacks right. I found a very informational thread about that and printed it and will be looking into that tomorrow if the weather cooperates.

 

[Buddafucco]

Good plan. Initiate, execute, succeed!

 

[gtsfirefighter]

::dunce:: It's amazing what swapping the number 2 & 4 plug wires and putting them where they're supposed to be will do for an engine. Fired up and purred like a kitten...till it warmed up and then had a little roughness about it. I'll find and fix, not worried. Now onto a new thread about the throttle body...

 

[Buddafucco]

:slap:

 

[Zumtizzle]

Bet you it runs real fast now too? haha