Question about 2002 Pontiac Grand Prix

2 Answers

My 2002 Grand Prix GT 3.8L Won't pass emissions. Testing center's scanner says car was recently worked on and that the mileage driven since is not enough to recycle check engine light. The ck eng. light has not come up in over a year. The light bulb is good. Since then we have had the engine scanned and no codes are showing up. Emissions test performed a 2nd time and again failed for same reason. Could the ECU possibly be bad? Any help would be appreciated.... About to pull my hair out!

Posted by on


2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

I would hope that's all there is to it but I've been driving it for several hundred miles between emissions tests. I believe the ECU isn't resetting like it should. I've replaced the usual suspects like O2 sensors, Spark plugs (all 6), cleaned EGR valve and even cleaned the engine!! Any other advice??

Posted on Dec 11, 2009

  • Lawrencej61 Aug 27, 2011

    did you fox the car, if so do tell me what you done


  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 1,586 Answers

Nope, you just need more miles. When the car's computer has been disconnected from power (such as when the battery is unhooked), it'll set what are called "readiness codes" when power is reapplied. It takes a certain number of miles to clear these - some cars require 50 miles, some 100 miles, and some (such as some Isuzu models) need very specific drive cycles to clear them. Once the requisite number of miles have been driven without issues, the readiness codes will extinguish and your car should pass.

Posted on Dec 10, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Car won,t start no lights no noise nothing on my 2007 Grand Prix GT it worked good yesterday what could I do

Try jump starting it ? Test battery , cables an connections ! There are a number of good videos on youtube for testing .

Nov 09, 2016 | Cars & Trucks

1 Answer

How do i reset my pontiac 2002 grand prix in orer to pass emissions?

A new cat what was the original code. Usually you need to drive the car for a while after changing a battery (1/2 hour to an hour) on the road so that the cpu as all the data it needs before going for etest especially the new etest machine. The place that change the cat is it the same place that is doing the emission test?

Aug 12, 2014 | 2000 Pontiac Grand Am GT

1 Answer

2002 Pontiac Grand Am GT - Failed Emissions Due to excessive number of readiness monitors 'Not Ready'

I would start with a good tune up ,spark plug , fuel filter , air filter
and depend of mileage o2 sensor change (over 100,000 km)
and retest for emissions
hope it helps

Oct 09, 2013 | Pontiac Grand Am Cars & Trucks

1 Answer

I have put 3 catalytic converters on my 2002 pontiac grand prix in the last 3 years, because it won't pass emissions, could something else be wrong?

Sounds like it might be running to rich.I would replace the fuel pressure regulator because it cause a rich condition.When the engine came on what was the number of the trouble code?

Jan 24, 2012 | 2002 Pontiac Grand Prix

1 Answer

2002 pontiac Grand Prix GT Malifuction Indicator Light Circuit.

When the light is on, the computer has detected a problem that you need to know about. You'll need to use an OBD2 code scanner for your vehicle. The scanner will tell you what the computer has detected.
You can borrow, rent or buy a code scanner from most automotive auto parts retailers... some will even help you use the scanner and interpret the results.

Mar 20, 2011 | 1999 Pontiac Grand Prix

1 Answer

I have recently put in a new catalytic converter in my 2002 Grand Prix. Before I put it in the check engine lights were on. After I put it in, it went off. I have driven it almost 400 miles and yet it...

Yes, pull the error codes from the computer, and follow thier indications, then take the emission readings to a mechanic and have them diagnose from that. PArts replacement is TOO expensive, only replace what is needed...

Sep 07, 2010 | 2002 Pontiac Grand Prix

1 Answer

1999 grand prix code P0108 and P0141

Until the problem is repaired the codes will come on

Jul 06, 2010 | 1999 Pontiac Grand Prix

4 Answers

The temperature gauge on my 2002 grand prix dose

the temperature sending unit on a 97 grand prix 3800 gt(which is also the coolant temperature sensor) is not accurate. the sending unit part of this sensor only sends info to the guage on the dash. the coolant sensor part sends info to the computer of the car. it is located under thermostat and somewhat difficult to get at. i had put a brand new one in and my temperature on my dash is all over the place---even with good thermostat and properly bled system. when i hook up a scanner to my computer, the coolant sensor is sending the computer(ecu??) what seems to be the right temp. anywhere from 194 degrees to 217 when hot. the guage however on dash go from 160 to 260 in less than 2 minutes.

Nov 16, 2009 | 2002 Pontiac Grand Prix

2 Answers

Emission control diagram on 2002 pontiac grand prix

There should be a sticker on the underside of the hood that includes the vacuum diagram. If you live in a state that does emissions testing I don't know if your system is different or not from a model sold in a state that doesn't.

Feb 24, 2009 | 2002 Pontiac Grand Prix

1 Answer

2005 pontac grand prix emission problem

EGR Valve needs replaced, because my gas cap light has been on forever even after replacing it and found out later it is more than likely the EGR Valve which when it screws up causes misfiring and poor performance down the road if not fixed soon enough and also leaves you with very poor gas mileage. The cost of the part ranges from $150 to $270. On the other hand it could also be Ignition Coil which costs significantly less but less likely for this to be the actual problem. Its cost is about $80 for the part.

Oct 09, 2008 | 2005 Pontiac Grand Prix

Not finding what you are looking for?
2002 Pontiac Grand Prix Logo

689 people viewed this question

Ask a Question

Usually answered in minutes!

Top Pontiac Experts


Level 3 Expert

83096 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22382 Answers

Jeffrey Turcotte
Jeffrey Turcotte

Level 3 Expert

8841 Answers

Are you a Pontiac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides