[SOLVED] No Spark, Cylinder 1 and 4

Months work on this problem but not everyday.

Issue: No power to 1 and 4
What I did to troubleshoot:

• swapped spark plugs
• swapped ignition coils
• ignition coil harness rebuilt
• new MAF
• new O2
• main harness swapped
• got injectors cleaned and new CS/Overspeed seals
• compression tested

What I noticed before this happen:

• It would drive good then suddenly at times especially in traffic, car will sound like a subbie (you can hear cylinders died). I would have to pull to side of the road.
• Another time I was on the highway and the suddenly, I would loose power and I would be going and my car was at full throttle. Pulled over and then the car would sound like a subbie and after some time, back to normal
• Another time I was leaving a packing lot and everything was good then went over a bump....a few minutes after, subbie.

What do I notice in troubleshoot:

• fuel smell in tail pipe
• P0172
• coil pack test for spark even when swapped... 1 and 4 .. no power
• everything at the top

I was planning to look at every ground wire but after changing the main harness, building another, and checking another, I am curious what else is needed. Any help would be appreciated.

 

Coilpacks on this car are batch fired; 1-4, 2-3 are linked directly. Hopefully it's something stupid simple like a bad ground (there's a small green wire on the HPFP bracket that you might want to look at) but might be the ECU or a pin in a connector or something.

 

The pair not firing intermittently points to a wiring problem more than a hardware problem

 

Also what happens if you unplug the MAF while you are having the problem

 

main harness swapped and coilpack harness custom rebuilt recently.

 

When I did it I believe last month, there was a struggle if I recall. I have a new MAF. Happy Memorial Day Brother. Long time.

Remind me of what this green wire looks like. It don't recall this. With all the harnesses swap, the ECU can be the issue. Spoke to Jordan of Overspeed and with everything I shared, he said ECU. I just want to drive my car and feel fast again...lol

 

Kind of hard to see but should be under this bolt. Should look alot like the one on the passenger engine mount but with a smaller wire.

 

I haven't had that bracket for years. Photo of an old photo. A ring connector is on it now.

 

Maybe pull it and clean all the surfaces with a brass wire brush...?

 

Check all of the connectors to make sure they are fully plugged in, the connectors aren't broken and that none of the wires have been pushed out of the connectors. Try wiggling the wires while the car is running to try and replicate the issue

 

Do we have a diagram of the locations of the ground wires to verify as well as the ground or power diagram for the 1 and 4 plug connectors?

 

I know we gave manuals in the metal member section.

 

I was a paying member for a while Brother. You know that. I have all the manuals you and others shared. I just don't see a ground chart in any or on the images etc.

I hope you been alright.

 

Hmmm

 

Grounds that I could find that is linked to the ignition coil harness connector cleaned and lubed as well as all the connectors. Got my neighbor to help. I couldn't show you everything clearly with one hand but this is where I am at....quick video.

https://www.dropbox.com/scl/fi/51f5...ey=f4ocspgd45eosa72g9xm96cby&st=9fdp2xro&dl=0

 

I wonder if it's something to do with the coilpack harness.

 

2nd time rebuilt by Kyle Rotter. See photo. He had a few post on FB about builds. I took him on as he had a few combos to make the bay cleaning especially that Eric Yarbough retired.

 

Yup, I know him!

 

Is that a good thing or bad thing?

 

Good guy.