vettewreck

iTrader: (1)

So a few months ago took my GT on a road trip about 2 hours. Car drove perfect whole way. Then I noticed the CEL flashing just I'm about to get off the highway and into my destination. Car is "missing" and doesn't like to run at low rpm. However NO noise, no knocking, clanging, nothing. Was told it might be stuck in limp mode. Disconnect the battery, give it 5 min.. hook back up, no change. Drove the car all the way back home 2 hours and at highways speeds its fine. Just around town its like a plug is out or something. Ok, so we scanned it and its a Cylinder 4 misfire. We change all the plugs. We swap wires. We swapped a coil. None of which changed the missing and code cylinder 4 misfire. But still... no knocking, to tinging, no banging.. no noise at all that from I understand would certainly be a failed lifter bc of noise. No smoke either. Of ALL the dod lifters failing threads I've read they all make horrible knocking or engine noise and can hardly drive. Mine has none of those. What else could this be if NOT a dod/failed lifter? Cam or crank sense gone bad and triggering a wrong code? What other way is there to maybe get the car out of limp mode if thats what its stuck in? Any thoughts at all? Ive been thinking more and more it just doesn't sound like a lifter bc there is NO noise. None.

87gnx

iTrader: (3)

Sounds like you did all of the right things.I'd bet it is the cam position, or crankshaft position sensor tho.Might take it to a better scanner, and find out for sure. I had to do that for the wifey's Beemer. It was worth the $100.00 for their scan. I fixed it at home. G./L. $0.02

Blackbirdws6

iTrader: (7)

Make sure the pcm did not **** the bed. Mine had a fault in the pcm causing a misfire two months after I bought the car brand new.

Marc 85Z28

iTrader: (8)

It sounds like you have a collapsed lifter. Remove the valve cover on the passenger side and crank the engine with ALL the coils disconnected. Check for lack of rocker movement on the intake valve.

I've done several collapsed lifter jobs, and NONE of them made any valvetrain noise.