Raise

iTrader: (31)

when i installed my headers, i took my cats off and just left the rear o2s hanging. a while after that, i installed my 224 cam and had it tuned by texas speed (mail order tune). i told them to delete my rear o2s. well, i noticed that even before my cam, ever since the header install, my engine would shake/jerk every couple seconds. u can really notice at idle, but even when rpms are up, u can still see it shake looking under the hood. u cant feel it while ur actually driving, but at idle its terrible. anyway, ive tried to pinpoint what it is, but i still havene had any luck. ive replaced plugs, wires, o2s. after texas speed sent me back my pcm,my ses light went off, but i dont know if they deleted my rear o2s correctly. can anyone tell me if this would be a possible cause of my problem? also, im having it tuned again very soon, so what should i tell him to look for?

kpowr82

iTrader: (9)

No, the rear o2's likely have nothing to do with it. The only purpose of the rear o2's is to monitor catylitic converter efficiency/failure. They do not affect afr at all.

Is the shaking you're feeling a vibration, or more like a rocking back and forth motion. Cause if it's a vibration, that is pretty common. It's primarily because of the location of the headers and y-pipe and the increased diameter tubing.

The vibrations are intermittent on my car also at idle. It seems like every couple of seconds, the vibes become more pronounced. Once it warms up though, the vibration becomes steady and much less noticeable.

Raise

iTrader: (31)

nah man, its a shake. with the hood popped, u can actually see the engine shake back and forth a few times.....and that happens every couple seconds. any ideas?

prostock_bigblock

iTrader: (11)

That happened to me once , and i couldn`t discover the problem , but after 1 year , I felt a kind of loosing performance ,(that was on 98 model) , so i decided to open the engine , however , we found a slight damage in pistons 1 and 3 , and we noticed that this happened only in 98 models . Why ? dont ask me .

Raise

iTrader: (31)

damn, well i hope my problem is different

kpowr82

iTrader: (9)

I hope so too. Are you throwing any codes? Maybe your motor mounts are bad, I doubt that, but maybe.

Raise

iTrader: (31)

well, its just coincidental that the shake showed up right after the header install. i dunno i dont think its the motor mounts.

bigMAC

It sounds like you need some poly motor mounts. It is probably because of the lope of the cam that is shaking the engine.

Raise

iTrader: (31)

well, for the second time, the engine started shaking after the header install, which was way before the cam.