[rcoe]

I also pulled apart the jumper harness for the MAF. Is there a reason that they added as separate sensor and spliced it into the MAF harness?





Think I am going to remove this jumper, cut the wires and solder extensions to the OE connector as the plug on the MAF end has the retention clip broken on it. I also have a new OE MAF sensor on the way.

I have checked just about everything and pretty confident there are no melted or shorted wires unless they are inside an otherwise undamaged taped and loomed harness.

So my next step might be to give up and bring it to a dealer to see if they can find a bad module or whatever it might be. Luckily I have a buddy who is the service manager at a Chevy dealer who says he has a guy that is into the performance stuff, was going to have him do the alignment on it next month but it might need to go there early.

Not something I really want to do but I am running out of options.

[KingLT1]

That is the break out harness for the air temp sensor.

[rcoe]

Originally Posted by KingLT1

That is the break out harness for the air temp sensor.

That is what I thought will just splice it off like they did. Just a and inch or so longer so I can get better routing.

[ctrlz]

This one's a bit of a mystery. I keep coming back to the timeline-- put the car away for a bit, and when you take it out again, it has major problems.
This just doesn't sound like a module going belly-up.

[rcoe]

Originally Posted by ctrlz

This one's a bit of a mystery. I keep coming back to the timeline-- put the car away for a bit, and when you take it out again, it has major problems.
This just doesn't sound like a module going belly-up.

I agree, I am tech support and troubleshoot Allison transmissions over the phone for a good part of my day at work. I like to think I am pretty good at figuring stuff out or at least being able to narrow down where to look.

But this one has me stumped. 1st Sunday in March pulled it out drove 15 miles to top off the tank and spray it down ran great. 2 weeks later it strands me after driving 25 miles into work.

Going to talk with my guy at the dealership this afternoon see if he thinks his guys would be able to figure it out.

[rcoe]

Well tonight installed new MAF and rewired the jumper harness, hooked boost box to the rear battery, tried starting and same thing. Still no codes other than the historic ignition codes that would not go away.

So was going to get it ready to bring to dealer new week.

Cleared codes, disconnected battery to hopefully reset all the sensors. Cleaned up all the wiring, zip tied everything back nice and neat. For some reason I decided to move the boost box to the front charge points under the hood and it fired right up and idled perfect smelled a little gassy for bit but that went away as it warmed up. Hooked the laptop up to get a couple logs.

Grabbed my phone just in case and took it up the road and seemed back to normal. Did one short pull up to about 90 acted a bit off on the top end, but is was only about 30 with wind chills in the teens out and it could have been the tires spinning a bit or just acting up because of the cold. Will see what King thinks when he looks at the log.

Only did about 10 miles but it felt back to normal. Let it sit for about 5 minutes after parking it and tried to start it back up without the boost box and it fired right up like normal.

Glad it is running but really wish I had found a definitive issue to know that it was fixed. I am thinking it might have been bad gas all along and it just took some time to get the fuel I could not drain out of the system or diluted enough. Or some kind of battery issue. Battery is only about a year old and always been on a tender (one designed for AGM batteries) when parked for more than a couple days and last week when I was gone for a couple days I had pulled the battery and put it on a trickle charger inside. I had also checked the voltage with a meter last night and it was resting at 12.5v and would drop to around 11.5v during crank then shoot up to 14v while running. So I cannot see how that would really be the issue.

Guess now I will try and recreate the problem.

Thanks for all the suggestion and help.

[KingLT1]

Looks better now. Drive it and let fuel trims relearn. The small pull probably felt funny because it looks like you had the nannies on and torque management was kicking in.

[rcoe]

Originally Posted by KingLT1

Looks better now. Drive it and let fuel trims relearn. The small pull probably felt funny because it looks like you had the nannies on and torque management was kicking in.

Yes nannies were on and I think the AFR was not plugged in.

Hopefully get some warmer weather so we can put the finishing touches on the tune.

[ctrlz]

Originally Posted by rcoe

Or some kind of battery issue. Battery is only about a year old and always been on a tender (one designed for AGM batteries) when parked for more than a couple days and last week when I was gone for a couple days I had pulled the battery and put it on a trickle charger inside. I had also checked the voltage with a meter last night and it was resting at 12.5v and would drop to around 11.5v during crank then shoot up to 14v while running.

Your pattern of problems has always sounded electrical to me.
Do you have another known good AGM or flooded cell battery you could swap for a trial?
That resting voltage sounds a little low for an AGM that has been on a tender. AGM should be closer to 13 V, particularly when (relatively) new. I would expect 12.8. The voltage drop while cranking seems acceptable.

[rcoe]

Originally Posted by ctrlz

Your pattern of problems has always sounded electrical to me.
Do you have another known good AGM or flooded cell battery you could swap for a trial?
That resting voltage sounds a little low for an AGM that has been on a tender. AGM should be closer to 13 V, particularly when (relatively) new. I would expect 12.8. The voltage drop while cranking seems acceptable.

Replaced the battery today, I think the old one was most likely good but I needed a new battery for my Bobcat. So I took the old one and put it in there, it is not near as particular about voltages as the Camaro.