anothersteveg

Hi Everyone. I have a 2010 Denali, lifters went bad, it's out of warranty so I did a cam and lifter swap. I just went stock, ls7 lifters and a cam (new) from a l9H engine. Had the PCM reprogrammed o delete the AFM.

On startup the idle is erratic and I'm getting codes for throttle position sensor errors, position not learned, etc.

Any ideas? I wasn't having any problems with it before the swap. Doesn't seem to have anything to do with the new cam, but kind of a strange coincidence. I cleaned the throttle body and MAF sensor. Now what to check?

Thanks

Steve

01WS6/tamu

iTrader: (36)

Did you drop the TB or clean it with carb cleaner and get cleaner into the shaft area. Make sure the connector is seated good and clear codes and see if it comes back.

03sierraslt

iTrader: (22)

What exact codes are you getting?

anothersteveg

So I cleared the codes and it was running much better. The idle still,has a little hesitation but those codes stayed out.

After about 5 minutes at idle I got p325 p327 and p353. Knock sensor and coil. Any ideas on this now?

Thanks

RS/SS 4.8

iTrader: (13)

Having pulled the heads to do lifters check your ground that goes to the driver rear of the cylinder head. Then check all your grounds.

anothersteveg

Ok, the latest....

Reset those codes. Ran great for about 5-10 minutes. Was getting ready to take it out for a drive when the idle started going erratic again (not bad, like a vacuum leak). The CEL light and stabilitrack off light came on. Neither of my code readers showed a code though? WTH?

Yes, I have checked those grounds and all is well. Checked all connections and good to go. But keep throwing out the suggestions please! Vacuum lines all look good too (will recheck for the 10th time in the morning) lol.

I have not done a tune other than the AFM delete. I just went with a stock cam from a 2009 Escalade w/o AFM but w/VVT. Was hoping it was close enough in profile to not need a tune, am I wrong?

What's next?

Thank you

Steve

Any other ideas?

anothersteveg

ok, an update for anyone that might find themselves in this situation.

So today, same thing. Would run great for a bit, then start running rough and throwing codes. Kept getting cylinder 3 misfire, knock sensor voltage, and coil voltage codes. I swapped plugs, then wires, then coils, no difference. Still showed the same. So i began tracing wires looking for shorts and continuity and eventually made it to the PCM leads. When I took off the bottom one, I saw moisture (think it was antifreeze). I cleaned it with MAF sensor spray and blew it out good. Must have got in there while my PCM was off being programmed?

Anyway, plugged it all back in and voila! Runs great now. Smooth and responsive, better than before. I don't notice any difference in power (sucks to do all this work for no change) but didn't expect too with stock cams. Gives me something to look forward too when I do my G8.

Overall, pretty straightforward. I dropped the oil pan to make sure I got the debris from the lifter out (wasn't much and everything looks good), and to make sure oil pump o ring was seated right. The oil pan was the biggest and most time consuming part. Specifically getting the front diff out while on the garage floor. Actually, getting it in was the hard part..... But at least I don't have that nagging voice saying "you should have dropped the pan"