[rcoe]

Well swapped out the O2 sensors fixed the dinged up wires though it appeared to be only cosmetic. Tied everything back up and checked anything that came even remotely close to the exhaust.

Was hoping to get all the old fuel out but could not get the last 5-6 gallons out, but did add 4.5 gallons of fresh 93.

Fired her up and it idled for over 5 minutes before it died. Then I got her to run again and could even slowly bring up the rpm's but still is not running right. Did not try to drive it as I am done pushing it for this week and it is starting to snow.

I did get a couple good long log files, even got it up to operating temp. While a 2k rpm my afr was sitting pretty steady at around 20 and I appeared to be getting random misfires on all cylinders. I do have the log files if anyone wants to take a look.

Still can't help but think it is bad fuel related as everything was running perfect, filled up drove for 20 minutes and it just started falling apart.

Well back at it tomorrow going to trace the vac lines from the BOV and another one that I believe goes to the alky control in the cabin.

Thanks for the ideas so far.

[KingLT1]

The o2 sensors are still pegged full lean and not switching. And the short-term fuel trims are pegged @ +30.5%. Something is wrong mechanically for sure.

[ctrlz]

Originally Posted by KingLT1

The o2 sensors are still pegged full lean and not switching. And the short-term fuel trims are pegged @ +30.5%. Something is wrong mechanically for sure.

I can't see the log files, but doesn't this sound like a big vacuum leak?

[rcoe]

Originally Posted by ctrlz

I can't see the log files, but doesn't this sound like a big vacuum leak?

It does but I cannot find it unless it is somewhere in the intake manifold and I guess pulling that is on the short list of what to look at.

Pulled the bumper and inspected the intercooler and piping as I had made some change there over the winter but everything looks and sounds good. Got under it while it was running and could not feel or see any exhaust leaks.

Here is a video of it running. Maybe something will jump out from it. At the end I am trying to give it some throttle and you can just hear on the video a hollow sound like it might be backfiring up thru the intake?

https://youtu.be/9PTlpw10RIo

[KingLT1]

Originally Posted by ctrlz

I can't see the log files, but doesn't this sound like a big vacuum leak?

Normally I would say yes but the fuel trims remain pegged even when the rpm is raised upwards of 2500rpm. Usually with a vacuum leak the fuel trims will correct above idle.

[rcoe]

pulled all the plugs, all good along with the wires. They all had a slight black carbon coat from running so rich but wiped right off and they all looked identical.

pulled the cover off the intake manifold no visible cracks or damage from the outside.

Not sure if the BOV on the front of the intercooler is supposed to be wide open at idle but it is, pulled the vac line and it shut. Guess I never noticed if it was that way before because of the bumper hiding it.

Pulling the intake manifold and maybe the valve covers tomorrow.

[ctrlz]

How about a little "old school" and hooking up a vacuum gauge?
Just throwing out suggestions...

[rcoe]

Originally Posted by ctrlz

How about a little "old school" and hooking up a vacuum gauge?
Just throwing out suggestions...

It seems to be pulling good vacuum at idle can definitely feel it and it is enough to snap open the BOV. Might pickup a gauge tomorrow just to double check.

[rcoe]

Here are the codes I am getting. What is going on with the ignition codes have never had these before?

Doing a quick search they both seem to be common with the drivers side rear harness issue. I popped the fender liner off just to double check this harness, it had been moved in the past but I pulled off the loom and tape just to make sure there was no underlying damage.

Battery is less than a year old and has been on a quality tender almost anytime it is parked for a couple days.

[ctrlz]

The P2534 and P2535 together make me think the ignition wiring is shorting. The low short is shorting to ground, the high short is short to voltage. Exposed wires are rubbing each other and a ground point somewhere.

I can't think of anything other than wire damage which would cause this. Those ignition codes should not show up together.

[KingLT1]

Check wiring harness next to headers on passenger side?

[ctrlz]

Originally Posted by KingLT1

Check wiring harness next to headers on passenger side?

Agree.
Also, pull up the trunk liner and look for water. Open underhood fuse boxes and do the same.

I think the car may be shutting down because it is losing the ignition "run" signal. There are probably other shorts too.

[rcoe]

Originally Posted by ctrlz

Agree.
Also, pull up the trunk liner and look for water. Open underhood fuse boxes and do the same.

I think the car may be shutting down because it is losing the ignition "run" signal. There are probably other shorts too.

Yep last night pulled everything out of the trunk, have a nice audio system in there, but pulling it out and disconnecting all the electrical connections.

Did check the fuse panel in the rear, looks perfect and all the fuses are good, battery is pretty new and seem good but might end up replacing it just to be able to rule it out.

I had also pulled the front fuse box loose and checked all around it, nothing and all the fuses are good. I had pulled this apart when installing my flexfuel sensor last Fall.

Looks like tonight I will dig back into the wiring see if I can find anything.

[rcoe]

Originally Posted by KingLT1

Check wiring harness next to headers on passenger side?

I can see the harness that runs along the top of the frame on the pass. side and it is clamped well out of the way of the exhaust. I can see and feel the entire length of this harness and it is still OE clamped and has no signs of wear or heat damage. In the middle of the image you can see the clamp holding the harness and this is the closest spot to the heeader.