Need help after cleaning
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
Need help after cleaning
Guys,
On my 87, I took the plenum, runners and valve covers off to be powdercoated. While these pieces were off, i cleaned the manifold using TB cleaner. Some of it might have gotten down into the engine. I just put everything back together and tried to start it up. It immediately starts but backfires, chokes and stalls. If I hold the throttle down it starts, revs high but chokes and dies again. if I play with the throttle it revs up but wants to die so I give it more gas and it revs up pretty high and then wants to die again. Meanwhile I'm doing all this in the garage and it got so bad my eyes were stinging so I shut it off for the night.
Question...is it just choking on the TB cleaner that got into the cylinders or should I check for something else? As I said it starts right up every time but won't keep running. Hasn't set a code either.
Thanks.
On my 87, I took the plenum, runners and valve covers off to be powdercoated. While these pieces were off, i cleaned the manifold using TB cleaner. Some of it might have gotten down into the engine. I just put everything back together and tried to start it up. It immediately starts but backfires, chokes and stalls. If I hold the throttle down it starts, revs high but chokes and dies again. if I play with the throttle it revs up but wants to die so I give it more gas and it revs up pretty high and then wants to die again. Meanwhile I'm doing all this in the garage and it got so bad my eyes were stinging so I shut it off for the night.
Question...is it just choking on the TB cleaner that got into the cylinders or should I check for something else? As I said it starts right up every time but won't keep running. Hasn't set a code either.
Thanks.
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
YES After looking over the whole wiring and vacuum assembly and not finding anything out of place I started re torquing all the bolts. What I found out is that i needed to go over everything at least twice. I found runner bolts (both top and bottom) and at least one TB assembly bolt that needed to be tighter so I guess it was sucking in air from a number of small places.
It started up with no problem and is idling fine...BUT, now I have a small/medium taping coming from the right side cylinder #6. Hope the heck I didn't drop something down there.
It started up with no problem and is idling fine...BUT, now I have a small/medium taping coming from the right side cylinder #6. Hope the heck I didn't drop something down there.
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
For anyone interested. I just had a friend/mechanic over to listen to my engine noise. He immediately diagnosed my knocking/banging as an exhaust leak and it turned out to be an EGR tube that is connected from the manifold near cylinder #6 and comes over the valve cover and goes down and attaches to another pipe down by the exhaust. It wasn't fully connected down at the pipe and exhaust was pumping noise which sounded to me like a banging. Put it together (temporarily - need a new clamp) and the car runs smooth and quiet. 
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Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
Originally Posted by greenvette95
With that cleaner you may have damaged an oxegen sensor, 
Hope not...I just replaced that about a month ago. But it was an easy swap so if I did, I can do it again. How would I know if I did damage it? I only changed it because it's been years and probably 50,000 miles since it was last changed. As I said it's running smooth now that I got rid of all the air gaps.