no power
901epd
02-20-2010, 03:37 PM
starts fine. but has no power. I have to play with throttle to get to speed. Help?:frown:
Mickey#1
02-20-2010, 04:43 PM
What year/model?
How old is the cat?
How many miles since the plugs, wires, air & gas filters were changed?
See if it runs better with the MAF sensor unplugged.
Check fuel pressure.
Check Throttle Position Sensor.
How old is the cat?
How many miles since the plugs, wires, air & gas filters were changed?
See if it runs better with the MAF sensor unplugged.
Check fuel pressure.
Check Throttle Position Sensor.
901epd
02-20-2010, 04:49 PM
:runaround:Vehicle is a 2002 pontiac, Grand Prix, small engine, with 171,000 km(104,00miles). Just tried new fuel filter with no success. Tune-up done at 70,000km... Code reads ;P0404. Runs nice otherwise. Can barely do 60kms/hr
1. I was thinking of straight pipe instead of the cat. Isn't the oxygen sensor ahead of the cat? So it should be uneffected?
1. I was thinking of straight pipe instead of the cat. Isn't the oxygen sensor ahead of the cat? So it should be uneffected?
Mickey#1
02-20-2010, 05:22 PM
P0404 is a code for the EGR valve. I don't have any experience with that code so I'm not going to be able to help.
BNaylor
02-21-2010, 07:43 AM
:runaround:Vehicle is a 2002 pontiac, Grand Prix, small engine, with 171,000 km(104,00miles). Just tried new fuel filter with no success. Tune-up done at 70,000km... Code reads ;P0404. Runs nice otherwise. Can barely do 60kms/hr
1. I was thinking of straight pipe instead of the cat. Isn't the oxygen sensor ahead of the cat? So it should be uneffected?
By small engine do you mean the 3.1L V6?
It sounds like a bad CAT converter. See link below. This notice covers 2001-2002 GM cars with the 3800 V6 engine but still applicable to GPs with the 3.1L V6. Check with GM of Canada and see if they will cover it under emissions warranty. If you run a straight pipe in lieu of the converter you will get codes like P0420 and a SES/CEL light unless a 02 simulator is used (post CAT) or PCM reprogrammed to preclude any converter efficiency tests. Plus it may be illegal.
Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=681283)
A bad CAT could affect the EGR system or even evaporative emissions system when certain tests are called on since the engine vacuum is affected or used so start there first. On the P0404 DTC the EGR pintle position error is too large when the test is run. (>15%). It could be an EGR valve electrical or mechanical issue.
1. I was thinking of straight pipe instead of the cat. Isn't the oxygen sensor ahead of the cat? So it should be uneffected?
By small engine do you mean the 3.1L V6?
It sounds like a bad CAT converter. See link below. This notice covers 2001-2002 GM cars with the 3800 V6 engine but still applicable to GPs with the 3.1L V6. Check with GM of Canada and see if they will cover it under emissions warranty. If you run a straight pipe in lieu of the converter you will get codes like P0420 and a SES/CEL light unless a 02 simulator is used (post CAT) or PCM reprogrammed to preclude any converter efficiency tests. Plus it may be illegal.
Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=681283)
A bad CAT could affect the EGR system or even evaporative emissions system when certain tests are called on since the engine vacuum is affected or used so start there first. On the P0404 DTC the EGR pintle position error is too large when the test is run. (>15%). It could be an EGR valve electrical or mechanical issue.
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