Hey all,

I installed my new plenum today and after hooking everything back up on the initial start it ran great. Ran around the block and was very happy. Then the trouble began. Went outside to fire it up again a little bit later and it began to run really rough. Idle speed was where it always is, 650 RPMs. But the engine was wobbling like an old V8 with cams would. Mind you everything is reconnected correctly so after a little research I thought it could be the throttle body. I have ~70K miles so that wasn't an unreasonable thought. Went and picked up a reman TB from the dealer and put it all together and had the exact same problem. The SES light would blink intermittently on the short trip around the block and would go off and on. It stayed on once but after disconnecting the battery it went away.

So I took everything off and re-installed all the original pieces, still same ****. AArgh.......... I performed all of the resets that you would normally do after a plenum/TB replacement so I'm at a loss on what to do next.

Any ideas to help a brotha out?

 

how are your spark plugs?

 

NGK iridiums w/ 15K miles. Car ran great before I opened it up so I have to suspect it has something to do with the install. I have had the plenum off 2 or 3 times before with no issues so

 

There's not a little red plastic straw stuck in there anywhere is there???

 

I know you said you did the throtltle body reset. But it can be tricky. Keep a watch with a second hand with you when you do it. After disconnecting the battery you may have cleared the ecm the car may run rough until it relearns.

 

or maybe your ecm needs to be updated

 

The fact that the issue started shortly after install of a new plenum suggests there's a problem, most likely a slight vacuum leak that is occuring when the intake plenum expands under heat. I suggest taking everything off and starting over again, paying close attention to pinched gaskets, vacuum hoses, intake ducting, etc. You might also want to check that the plenum is true. What plenum is this? Also, buy/borrow a vacuum gauge (MityVac brand) and test the vacuum. If it's low or boucing, you've got a vacuum leak.

 

^Good point.

What about that little cap on the front passenger side of the upper plenum? If you knocked it off during the install/uninstall/reinstall, that would be a vacuum leak there.

 

[QUOTE=Blue [SIZE="5"]Dream;5035291]Hey all,



So I took everything off and re-installed all the original pieces, still same ****. AArgh.......... I performed all of the resets that you would normally do after a plenum/TB replacement so I'm at a loss on what to do next.

Any ideas to help a brotha out?[/QUOTE[/SIZE]]



My guess is a vac leak. maybe a hose got knicked, thats all it takes sometimes.

 

I'll give that a shot after I try it all over again.

I bought a chromed plenum off a member on here. I'm going to tear it all down this morning and start over. The fact the issue is exactly the same with the stock plenum suggests to me that it isn't a plenum issue. Good point about testing the vacuum, I may go that route if I can't fix it by starting over.

It's there on both plenums.

I'll check them all again. I appreciate all the responses. If anyone has any more ideas I'd love to hear them. I'm supposed to go to Houston this weekend for a mini family reunion so the timing of this is pretty crappy. Back to the garage in a little bit.

 

^ Not working thru the night, are you Tim?

 

Nah, I was worn out after working on the car for 5 hours and crashed around 9. Up bright and early to have my coffee and check the responses here. I'm usually up at 5 anyway.

 

This happened to me when I changed my spark plugs. I put the original plugs back in on the driver side, problem went away. Put the new plugs back in on the same side, problem did not reoccur and has been fine for > 20k now. All I could figure is one of the coils was not on properly.

Not that this is what's happening to you, but you seem to be kinda grasping so I figured I'd throw it out there.

 

that rubber funnel thingy by the oil cap isnt pinched between the upper and lower plenum is it? Also, are you sure the air hose on the battery side of the plenum is re-hooked up?

 

Thanks for all the replies peeps. Tore it all down this morning and found a coil plug loose that went to a spark plug. Did all the resets and it runs like a champ!!

Now I'm headed to Houston!!!!!!!!!!!