Have a 2005 corvette - big cam and stroker LS 2 ( 404 CI) ( yes new reluctor wheel on new crank BUT car starts and runs fine until it acts up ) - everything going great with driveability before car starts to really deteriorate to the point where it would stall and not stay running with super rich black smoke and backfires. I noticed in the HPTuner log that the MAF is clearly dropping out frequency wise - the trace is sinusoidal with varying frequency - but has vertical drop out to zero and back like from 3-4K Hz to 0Hz and then back again .. I looked at earlier logs where it was running better and it did not have the drop outs at all. I have also noticed that my Tach needle on my cluster also bounces to zero and back to whatever rpm it is at ( instantaneously) when it starts to act up, the duration of zero tach needlestaying at zero increases the with the car;s deterioration in driveability. Car runs fine when its cold, but slowly deteriorates to the point of dying. Then I have to wait for it to cool down before I can start this cycle all over again.
What I have done: 1) new delphi MAF sensor 2) new crank position sensor 3) new larger battery w/ larger capacity wise, ( ECU voltage WAS all over the place and I suspected weak battery that was not recovering after frequent restarts - so I put an interstate grp 25 megatron + w/1000 cold cranking amps - battery voltage now stable. But - still funny MAF reading.) 4) checked alternator.
5) I have read in some other corvette centric forums suggest replace starter - some how this drags down wiring harness voltage ( sounds crazy to me - thus have not doe this yet).
CODES: Initially codes indicated crank position sensor & MAF.
Because the HPtuner suite looks at the data from the computer side, I dont know if it is the cars wiring or sensors going away - or the computer E40 starting to die ( as I said gets worse with time and temperature from cold start).
PLAN: Scope out the CKP, CMP sensors and MAF sensors at the ECU.
OTHER: Did notice the ECU molded fiber glass frame mount was cracked and I believe this car has had a slight smack in the vicinity of the ECU mounting.
This is kicking my butt - any ideas appreciated Rick
