2003 Pontiac Grand Am = Frustrating

Specific repair issues for all GM cars + FWD vans
Post Reply
Tim Martin
2.5K Uber Ninja Contributor
2.5K Uber Ninja Contributor
Posts: 2642
Joined: Wed Feb 04, 2009 1:28 pm
Location: PA

2003 Pontiac Grand Am = Frustrating

Post by Tim Martin »

This car is taking frustration to a new level. This car, an 03 Pontiac Grand Am GT with a 3.4L engine an 102,000 miles on came in for emissions inspection an it had a code PO401. We diagnosed a faulty EGR valve, replaced it an proceeded to reset the monitors for emissions inspection. The one that has not reset is the one for the heated O2 sensor. Mode 6 shows no faulty data, I can manually do the heater test with my scan tool an it works, why wont the readiness monitor set to ready? What am I missing or is there something I need to do? Typically this is a piece of cake thing but not so with this one.
User avatar
steven kiser
5K Holy Smokes Contributor
5K Holy Smokes Contributor
Posts: 6184
Joined: Fri Jul 06, 2007 4:58 am
Location: eastern ma.

Re: Frustrating 03 Pontiac Grand Am

Post by steven kiser »

As a rule I'll drive the vehicles to reset. The heater circuit may need a few other monitors to be reading before it runs. Sometimes the fuel level has something to do with the emissions running.
never argue with a fool, they'll drag you down to their level and beat you with experience
Tim Martin
2.5K Uber Ninja Contributor
2.5K Uber Ninja Contributor
Posts: 2642
Joined: Wed Feb 04, 2009 1:28 pm
Location: PA

Re: Frustrating 03 Pontiac Grand Am

Post by Tim Martin »

Well Steve, I agree with ya. The fuel level is just barely below the 1/4 mark. Here in PA for an 03 model all but one monitor needs to be reset be4 emissions inspection can pass. I typically do not get excited if an evaporative systems monitor does not reset cause that one is usually the most difficult to run. The drive cycle for the O2 heater test is to start the engine with coolant temp below 122 degrees, idle in drive for 2.5 minutes with foot on brake, ac and rear defroster on, then drive at 55-60 mph for 3 minutes. Well I have done this time and time again with the same result - the heater readiness monitor does not switch to "Ready". It is so frustrating cause we dont have time for this an the customer wants his car. We get stuck in between the state an the customer in a case like this.
User avatar
ricmorin
5K Holy Smokes Contributor
5K Holy Smokes Contributor
Posts: 5967
Joined: Mon Jul 25, 2005 10:11 am
Location: New Hampshire
Contact:

Re: 2003 Pontiac Grand Am = Frustrating

Post by ricmorin »

There are two stages to the monitor according to my information. The second part requires an engine temperature of 176 degrees minimum to finish. Perhaps the engine is running just slightly cool enough to not get past this but warm enough to not set a PO128?
Ric Morin - Volunteer Forum Moderator, Shop Owner, ASE Master L1
Motorcar Alternatives, LLC
603-622-6434 x203
www.motorcaralternatives.com

I find my life is a lot easier when I use Special Orders
User avatar
steven kiser
5K Holy Smokes Contributor
5K Holy Smokes Contributor
Posts: 6184
Joined: Fri Jul 06, 2007 4:58 am
Location: eastern ma.

Re: 2003 Pontiac Grand Am = Frustrating

Post by steven kiser »

Totally forgot that. A bad t stat will cause that as well as a bat cts. I hook up my scanner read the operating temp and hit the rad and where the upper rad hose attaches to the engine with an anfared temp gun. If this had a heavy duty radiator you may need to disable the fan or restrict the air flow. Great point on the temp, I totally pulled a blank on that one.
never argue with a fool, they'll drag you down to their level and beat you with experience
Post Reply

Return to “GM Cars”