Since installing the new cam in my car it's never felt like it is really running as good as it should be (very slight difference after cam install). Trhgouhout the last couple weeks seems like the car keeps running worse and worse. Initially i had the valves set to 1/2 turn past zero lash (found out on a roller setup this is wrong obviously). So this weekend i get around to adjusting valves and set them all to 1/8th. Now when i drive the car it feels like a complete dog...my purely stock T/A would smoke it. It just doesn't want to go anywhere. Why would readjusting the valves do this - or is this just circumstantial? It feels like the timing is ALL messed up...i haven't had a chacne to scan it with Freescan, gunna do that this weekend when i can get my hands on a laptop. But like i said, feels like the car has progressively gotten slower, and i notice a dramatic difference since adjusting valves on sunday. In fact, now the car seems to be idling rougher and running worse than before i put my PCMForless tune in. I know this is pretty vague...but any general guidance on troubleshooting this...where should i start?

 

1/2 turn should have been fine (unless you have Comp R lifters) and if it has run terribly poor ever since the cam install, I might suspect that you got it a tooth off on the cam sprocket. Hopefully you have checked any obvious hoses and connections to rule them out.

 

A little more history: Well, car hasn't run worse since cam install. It seemed to run at least as good as if not maybe a little better for baout an hour after i initially got it running and got the new tune uploaded. The lst 3 hours or so i have put on the car since seme to have gotten progressively worse.

Initially after cam install it wouldn't start. I tore the front apart and check the cam sprocket - it was good turned out ot by my opti drive from the cam was in the cam sprocket wrong (not sure how my friend helping me at the time managed to force that in wrong!!!). Anyways since i'v epretty much put the engine together twice at this point i had a good chance the second round to reverify all hoses and connections.

So I guess my real question is will scannign to check for codes help diagnose the problem any? Is there any log data i could look at that might help? IS it even remotely possible this is a PCM/Tuning problem causing timing issues?

As a side note: this time around on valve adjustment i was under the car turning the crank...had my dad up top adjusting hte valves. Now, he has done this dozens of times but since his head injury he tends to sometimes get a little forgetful/careless over simple things - if theoretically the valves were all adjusted to maybe slightly less than zero lash could that cause terrible performance? Since adjusting them i seem to have a lot more valve noise than before...but should i expect that much more if they were adjusted to 1/8th passed zero lash as compared to 1/2 passed?