93 grand am v6 failed emission HC at idle

D

Duramax

New member
Joined
Sep 26, 2011
Messages
10
Reaction score
0
Points
0
Well my daughters grand am failed the emission test at idle HC(ppm) and co. Limits are 220 and 1.2. Her car was at 514 and 1.28. Also her cooling fan stays on all the time. Plus the hesitates from a dead stop. Any ideas would great.
 
Last edited:
How many miles on the car? How many miles since a tuneup, plugs, filters, etc?
 
Not sure on miles. I think between 160k and 180k plugs all changed last year they still have the correct gap and look good all tan and white. I know the fuel filter needs changed air filter not sure. Oil + filter last week it passed the cruise test the A/C compressor is engaged even when it's turned off on the dash I that matters.
 
Well changing the filters would be a great place to start especially the air filter if it's dirty. Adding a bottle of fuel injector cleaner to the tank would also be a suggestion. Are you saying with the climate control switch set to off the A/C compressor and fans are running? If so I would check if you have a stuck relay.
______________________________
 
Yes fan runs even when the switch is off. I pulled the heater fuse and it turned off. Also idle went up a little but still hesitates when you crack the throttle. Did a compression test with the motor hot. It ranged from 170 to 190 even cylinders were the highest
 
Would the sending unit for the fan cause it to stay on and where is it located? I'll check the relay
______________________________
 
the fan is on because the A/C is on, regardless of engine temperature if you turn on the compressor the fan runs
 
I was wrong. The A/C compressor does turn off when the selector switch is off,but the fan runs constant still. Changed the fan relay and made no difference.
 
What is this plug for? Its below the power steering pump.
plug002.jpg
 
Whats this plug for?
plug002.jpg
______________________________
 
I also cleaned the Mass Air Flow Sensor/Meter
and IAC. It seems to run alittle better. changed the air and fuel filters also.
 
Well I tried to change the fuel filter previous owner screwed up the fuel line. Cant get the filter to tighten up. Need to replace the end of the line. That should be fun. I hate stupid people who mess with cars.
 
Have you considered a faulty engine coolant temperature sending unit? It is common to the problems you have.
______________________________
 
Check engine light is off unless the bulb is burnt out, It passed the cruise test. So I dont think its in limp home mode, but then again I've never had a car do that. I did think about the temp sender being bad,but my daughter wants a new car. I'm waiting on a repair manual to come in the mail.
 
You must log in or register to reply here.

Share this page

Back
Top