I would check to see if there is any Vacuum hoses on the transmission.
On GM Trucks/ Vans there is a small pod on the side of the transmission that has a vacuum hose to assist in shifting esp for getting into the passing gear on the highway these hoses often break making a vacuum leak to the engine that would also make your engine race or idle too fast would be a better term. It will be obvious when you crawl under the van look on the side of the transmission around the pan depending on what type of transmission it is it could be in different locations. there are different automatic transmissions GM uses.
Look for a small round tin thing Called the Vacuum Modulator link below is a photo of a couple http://spacecoastfieros.com/tech/440-4T60/Modulator.jpg that is threaded into the transmission or bolted. if that hose is not broken at that end follow the hose up to the engine see if it has broken up there or it may have just come off for what ever reason.
That would be my guess and the first thing I would look for.
Hope that helps
If that isn't the problem then it could be something else possibly electronic if it is EFI. alternator wire disconnected could make engine idle fast on EFI.
The ECM on the Vandura 2500 is under the Driver's seat.
My 93' vandura has a 5.7 liter 350cubic inch engine.
It does not take freon. The 1995 GMC Vandura uses the new R134a.
Hi: Have you an elctrical diagram for the cruise control of a Citation GMC 1985 (Vandura). Regards.
No, the GMC Vandura is a van. If you have the Starcraft conversion, the van is technically considered a station wagon for insurance purposes (much cheaper).
The 91 Vandura G2500 Instrument Panel Cluster Relay is located on the dashboard.
my 1992 vandura 6.2 diesel short bus weighs 10,000 lbs
I have a 1995 Vandura and power sofa fuse is under hood. There is a fuse block there too with iterior electronic gizmos on it.
There are to sizes 110"and 125".
IIRC, 700r-4
10-12
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