A whole slew of check codes out of nowhere, help!

[KingCobra07]

Hey guys...looking for some guidance.

Car is an 08 GT500, MMR shortblock, crower stage 3 cams, and a 4.0L blower. Had Lund (working with their new guy, Dakota) send me a startup tune, and car was running fine. We made it up to revision 5 to do WOT pulls, and something went wrong.

On the first WOT pull, went foot to floor for all of 3rd gear, took my foot off the gas, hit 4th, and then the car suddenly died and wouldnt restart. We reloaded the tune, and still wouldnt start. Only crank. Checked all the fuses under the hood and found a blown one for one of the engine controls. Replaced it, car started up, but wouldnt idle. Goes into failsafe and gives me these 4 codes....

P0102 MAF curcuit A too low
P0135 o2 heater curcuit
P0155 o2 heater curcuit
P1488 pvc heater control

This is where Im at. Ive swapped the MAF sensor from a running car, but changes nothing. Is it possible my PCM fried? Ive reloaded the stock tune as well as previous revisions but it still comes out the same. Any input would be much appreciated.

 

[Sielmo]

Hey guys...looking for some guidance.

Car is an 08 GT500, MMR shortblock, crower stage 3 cams, and a 4.0L blower. Had Lund (working with their new guy, Dakota) send me a startup tune, and car was running fine. We made it up to revision 5 to do WOT pulls, and something went wrong.

On the first WOT pull, went foot to floor for all of 3rd gear, took my foot off the gas, hit 4th, and then the car suddenly died and wouldnt restart. We reloaded the tune, and still wouldnt start. Only crank. Checked all the fuses under the hood and found a blown one for one of the engine controls. Replaced it, car started up, but wouldnt idle. Goes into failsafe and gives me these 4 codes....

P0102 MAF curcuit A too low
P0135 o2 heater curcuit
P0155 o2 heater curcuit
P1488 pvc heater control

This is where Im at. Ive swapped the MAF sensor from a running car, but changes nothing. Is it possible my PCM fried? Ive reloaded the stock tune as well as previous revisions but it still comes out the same. Any input would be much appreciated.

Bottom line, I have no idea but smarter folks out there likely will have ideas.
First, check the simple obvious stuff. For example, vacuum lines, intake, pvc etc. I threw a bunch of codes once and thought the worst but it was only my vacuum line which popped off.

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[Willie]

You didn't mention which fuse blew, but check / recheck F47 (15a). If it's good, then I believe the PCM power relay may be the problem. It can be swapped with either of the fan relays for a simple and easy test.

 

[KingCobra07]

You didn't mention which fuse blew, but check / recheck F47 (15a). If it's good, then I believe the PCM power relay may be the problem. It can be swapped with either of the fan relays for a simple and easy test.

We were on the side of the freeway freaking out that we were gling too gett hit by a car. I dont recall which fuse, but i do know it was one of the engine fuses. Ill check the relay thing tomorrow. Thanks Willie

 

[Catmonkey]

A common theme for the first 3 codes have to do with voltage. You might see how much voltage your alternator is putting out. I don't see that last code in my service manual, but it is for a 2012, are you sure it's correct.

 

[KingCobra07]

A common theme for the first 3 codes have to do with voltage. You might see how much voltage your alternator is putting out. I don't see that last code in my service manual, but it is for a 2012, are you sure it's correct.

Yeah, thats what the Ngauge is reading out under CEL codes. I dont understand why the pcv would have a heater, but who knows?

And the car has a brand new PA alternator with their big alternator lead wire.

 

[Willie]

Every component that set a code is powered by fuse F47. If the fuse is good, then the PCM power relay is upstream. I think that you had a voltage surge under throttle, which blew the fuse or possibly damaged the relay....

Willie

 

[KingCobra07]

Every component that set a code is powered by fuse F47. If the fuse is good, then the PCM power relay is upstream. I think that you had a voltage surge under throttle, which blew the fuse or possibly damaged the relay....

Willie

Swapped out the relay with the rear defroster and then put a new fuse in F47, problem solved! Thanks for all the help guys

 

[RedVenom48]

Honestly, i really want to know what would pop a fuse during a wot pull like that. Any chance of a chaffing harness?

 

[Willie]

The only thing I can think of that may have caused a surge (or spike) is the voltage regulator experiencing a hiccup during high rpm's. I would definitely carry spare fuses just in case it occurs again. And if it does, I'd say replace the alternator, the regulator is internal...

Willie