Q: My car shakes while it idles but says there is an evap system leak?

asked by on September 30, 2016

For about three weeks now my car has been shimmering while it idles. The check engine light is on and I had it read, it said that it was an evap system leak. Recently I've had the canister purge valve replaced but that did nothing. I've also checked the gas cap and that to seems fine, but do an evap system leak and rough idling go hand in hand? Are they two separate issues? And does that indicate where the leak could be since the engine is shimmering?

My car has 130000 miles.
My car has a manual transmission.

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An evap leak is the same thing as a vacuum leak. A vacuum leak will certainly cause the engine to run roughly. I would recommend having your vacuum levels checked with a vacuum gauge by a qualified professional to determine whether they are in specification. If the vacuum levels are low, I would then recommend getting a smoke test performed on your vehicle. This test will insert smoke into the engine through the brake booster hose and the smoke will be emitted from where ever the vacuum leak is. Once the leak is found, have it repaired as soon as possible in order to resolve the rough idling issue. Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs.

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