vacuum leak help please
10-28-2014, 04:51 PM
#1
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vacuum leak help please I have a 2002 Trans Am ws6 and i had a service engine light come on so i got the codes read and i have a vacuum leak. I already tested the gas cap and that was not the issue. So I want to know if there is a good or common place to start looking for leaks. Thanks ahead of time and also the car has 11k miles so im sure its just because of something sitting for too long.
10-28-2014, 09:51 PM
#4
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Back in the old days before computers, we would take a can of carb cleaner and spray it sparingly around potential leak areas. It will tell you where the leak is very quickly.
10-29-2014, 06:16 PM
#5
Is there a code for vacuum leak specifically or was that speculation by the person that read your codes? Gas cap issues are usually related to EVAP and similar so let us in on the train of thought here. To detect vacuum leaks, you can Light a cigarette and move it all around potential leaks.. Carb cleaner works well also but is a little dirtier.
10-30-2014, 01:28 AM
#6
It could also be from the small vacuum port on the back of the intake manifold. This is where the AC and air injection system get it's vacuum from. Also check the EVAP hard plastic tube and where it hooks up the driver side of the intake manifold for vacuum leaks.
10-30-2014, 10:59 AM
#7
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what code did you have, p0171 system too lean, would be an engine vacuum leak, p0455 p0456 p0442 are all evap codes and be caused by fuel vapor leaks, gas cap can pass test and still not seal, its more of how does it feel when youre tightening the cap, if you tighten the cap and its starts clicking with little resistance before it starts to click then the cap is probably not sealing like it should, it should seal then have a little resistance then click, cap is generally where evap leaks occur, but purge valve and any vapor hoses coming off fuel tank can leak.