1999 Chevy Blazer emissions

Tiny
SYFAZ777
  • MEMBER
  • 1999 CHEVROLET BLAZER
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 110,000 MILES
My blazer will not pass a smog test. What do you reccomend changing? When the a/c is on sometimes I can smell gas. And when I stand behind the car at idle, there is a gas smell but no dripping gas out of the exhaust pipe. Does the a/c suck air from the outside or recirculate inside air? Why is there a gas smell inside the car occasionally when the a/c is on? Please help me
Saturday, July 24th, 2010 AT 10:16 PM

3 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Hi syfaz777,

Thank you for the donation.

First thing to do is to understand what is wrong causing the test failure.

Can you pprovide the details of the test that failed?

A/C would either recirculate or get fresh air from outside deoending on the setting.

If gas fumes is getting to the cabin, then there must be a gas leak somewhere. As to it getting to the cabin, it could be an air leakage somewhere or the recirculating mode had been set to fresh air.
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Sunday, July 25th, 2010 AT 8:57 AM
Tiny
SYFAZ777
  • MEMBER
  • 5 POSTS
1999 chevy blazer ls
well, I know for sure there is no switch or setting to change from recirculate to outside air. THERE IS NO SWITCH, only a/c on or max a/c. I will try to get the test results, but now I know for sure there is gas or fluids dripping out of the exhaust pipe. Any suggestions?
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Sunday, July 25th, 2010 AT 11:31 AM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
If your system is manual HVAC, then it is not equipped with recirculating /fresh air features. Under such circumstances, you would have to check for air leaks from areas such as the firewall, look out for dislodged or broken/torn plugs etc.

If fuel is coming out of the exhaust, it means excessive fuel is getting to the cylinders or at least one cylinder is not firing correctly.

Possible causes are :
1. Bad spark plugs or related parts.
2. Compression.
3. Faulty injector.

But I believe it is fluids rather than gas. Fluids would drip off as combustion from the engine would produce water vapor and after a while this would accumulate to be discharged from the exhust as fluids.

Is the Check Engine Light indicating?
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Sunday, July 25th, 2010 AT 2:46 PM

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