Code 41-Bucking On Light Acceleration

[Scoobum]

A gentleman contacted me. He had his engine rebuilt...and now the SM is showing code 41...and is bucking at light throttle. Read up on it and it could be the cam sensor, ignition module or ECM. With it bucking at light throttle...is there any tipoff to what it is? I've got known good spares for everything. Possible they installed the cam sensor incorrectly?

[PacecarTA]

reset cam sensor properly

[Scoobum]

Thanks so much Paul. Car is 90 minutes from my house...and I wanna get it right...and not go back.

[PacecarTA]

if the sensor is badly worn at the bottom tanges where the wave washer is it can do this as well

its possible it was set originally and the new chain did its initial stretch and has changed that
also look for obvious like maf plug disconnected

[Scoobum]

Will do Paul. I'm off Sunday...and if you can think of anything else by then...please post up. Once again...thanks .

[Steve Wood]

http://www.vortexbuicks-etc.com/code_41.htm

good troubleshootin g routine from the factory.


Being old fashioned, I would start off by cranking it up and seeing if the problem goes away when the sensor is unplugged and the car runs in batch mode.  If it does, be sure it is set correctly and there is no excess play in the shaft.  If it looks good, then it probably needs a new cap.

[Scoobum]

I was out yesterday and it only does it in OD with a load on it. I swapped out the coil pack and ignition module...no difference...a nd it has a new ECM. I pulled a plug and he has some NGK's in it that I wasn't familiar with. I called Norbs and he said they were a very cold plug. There's black soot blowing out the exhaust on the driveway. I'm guessing the plugs are so cold they won't fire with a load on them...and the gap looked wide. I suggested he order the original wires for it and 44's. He ordered the parts this morning. If this doesn't cure it...then I'll reset the cam sensor...and check it as you guys have suggested. I'm open to other suggestions. Oh...he had a Capsoers cam sensor cap on it...and I had him swap back to the stock cap...and the code cleared...and didn't return when we tested the car with the coil pack/ignition module swap.

[Steve Wood]

someone looked in the book and saw the 0.045" that is listed and did not know the turbo uses 0.035"
the NGK UR-5 is the usual plug.  It's equivalent to the AC 42's.  NGK plugs run opposite with regard to heat range so that an NGK UR 6 is colder, not hotter than the 5 where the UR-4 is more like the 43