hockeybawler
New member
Does this happen to everyone's grand prix? I have an 04 and every time I turn it on my cars idle surges from around 500 or so all the way up to about 1000. Any input would be appreciated, thanks!
A/C makes cars idle surge
- Thread starter hockeybawler
- Start date
Scottydoggs
Killa Bee
it only does it once?
it could be the hvac taking vacuum and causing the idle surge. or maybe you got a vac leak in the vac line off the top of the sc to the firewall.
it could be the hvac taking vacuum and causing the idle surge. or maybe you got a vac leak in the vac line off the top of the sc to the firewall.
hockeybawler
New member
Nope it will continuously surge until I shut the A/C off. I have tried to check for vac leaks before with carb cleaner because I think I may have one but I can never hear a difference in idle. Think it may be time to take it to a shop and have them run smoke through it?
Scottydoggs
Killa Bee
put the defroster on, see if it still does it. as the compressor turns on with defrost too.
hockeybawler
New member
I will when I go out to my car in about an hour
hockeybawler
New member
Sorry it has been a few days but I tried the rear defroster and it did not make the rpms rev. Still the A/C makes them rev.
Scottydoggs
Killa Bee
that one line that runs to the fire wall, its the one that power's the hvac, maybe the box inside the car is leaking, ot the line broke in the engine bay.
you change the battery lately? sometimes the line can break when doing that. it runs down the pass side fender to under the fuse box, some cars have a t some dont, the T is under the fuse box, one side goes into the cars harness into the cab by the frame, the other side runs across the rad support to a vac ball in the d/s fender, take the head light out to see it.
pic of said T under fuse box. if you dont have a T the line goes just to the cars wire harness.
you change the battery lately? sometimes the line can break when doing that. it runs down the pass side fender to under the fuse box, some cars have a t some dont, the T is under the fuse box, one side goes into the cars harness into the cab by the frame, the other side runs across the rad support to a vac ball in the d/s fender, take the head light out to see it.
pic of said T under fuse box. if you dont have a T the line goes just to the cars wire harness.
hockeybawler
New member
I changed the battery in the winter so that could be it. I did not notice any bad lines but I will check everything tomorrow to find out what exactly is going on with it. Thanks for the help and suggestions!