Vacumn related problems?
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 3,252
Likes: 6
From: The Colony Tx
Vacumn related problems?
I have 3 problems that are possibly related and have not been able to find the answer using the search function ( I may be seach challenged
). Stumble on take-off, occational backfire, and when the cruise is on it works fine on a level road, but falls off going up hill.
Do these all sound vac related or am I off track? I did find a cracked plastic line that runs from the left side of the engine by the distributor over to the plenum on the right side. I will be replacing it tomorrow and see if any of these problems seem to go away.
). Stumble on take-off, occational backfire, and when the cruise is on it works fine on a level road, but falls off going up hill.Do these all sound vac related or am I off track? I did find a cracked plastic line that runs from the left side of the engine by the distributor over to the plenum on the right side. I will be replacing it tomorrow and see if any of these problems seem to go away.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
The cracked line should be the HVAC/Cruise line (do either work?), but I'd suspect the MAF or at least want to rule it out. Unplug it and see if it goes away or scan it to see if it's rich or lean and then unplug it to see if fuel delivery swings the other way.
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 3,252
Likes: 6
From: The Colony Tx
Line from plenum was definately cracked. Replaced and no difference. Will try the MAF tomorrow.
I have tried using a hose to isolate vac sounds and the cruise seems to have no leaks. So the not holding speed going UP hill doesn't make sense. It holds just fine if on a level road.
I have tried using a hose to isolate vac sounds and the cruise seems to have no leaks. So the not holding speed going UP hill doesn't make sense. It holds just fine if on a level road.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Low vacuum - acceleration and load - relies on the Vacuum Tank to make up for the shortfall. The HVAC hose runs from the Plenum, to a Check Valve, wherein one side contines through the Firewall and another goes to Cruise and the Vacuum Tank. From what you describe, nothing is getting to the Tank, but if you patch it up and the problem continues, apply 10 inches of vacuum to the Tank with a hand held pump. It should hold.
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Seperated them and it ran good. $90 to Jegs will fix mine. Hope yours is as easy.
