2002 GP SE - Won't Start Periodically.

Periodically, car will not start. When car is cold there has never been a problem - starts right up. Car has 100,000 miles, recently had transmission rebuilt, new plugs and wires, new fuel filter, gas cap. Car has been maintained since day one.......It appears to be a vapor lock of some kind??? Car drives great other wise...never conked out etc..Seems to happen at randomly. Can drive car for 20min or 2 hours and it runs fine, however when you attempt to restart the vehicle(I'm guessing before it cools down) it won;t start. Sounds like it wants to start but doesn't. If it sits for 20-30 minutes it starts right up. Any how, it happens at random.....but car needs to be reliable.

No codes are coming up. And current problem has only happened a handful of times. Car was seen by dealer and only thing they could come up with is the gas cap needed to be replaced for $100.00. They never picked up that the transmission was ready to go....Needless to say car is not going back tothe dealer.

Any ideas would be appreciated.......Thanks

Check and make sure the fuel pressure regulator is working properly. It may be leaking down when the car is hot and not holding pressure. You will need to rent a fuel pressure guage to see what the FPR is doing. The only other thing is that the fuel pump may be going bad and when it heats up it will not start. I would however check the regulator first as I think that may be your problem.

Check and make sure the fuel pressure regulator is working properly. It may be leaking down when the car is hot and not holding pressure. You will need to rent a fuel pressure guage to see what the FPR is doing. The only other thing is that the fuel pump may be going bad and when it heats up it will not start. I would however check the regulator first as I think that may be your problem.


GTP Dad, can you advise were the fuel pressure regulator is located??
How hard is it to replace the regulator & fuel pump? I've been told the fuel pump is in the trunk area or do you have to drop the fuel tank to change that????? I appreciate your help....Thanks!

What size engine to you have? If you have a 3.8 the FPR is on the drivers side on the front of the engine. Remove the engine cover and the FPR looks like a small round can with a vacuum hose on the top. On the fuel rail there should be a shrader fitting that you can attach a fuel pressure guage to the rail. It looks like a tire valve. The connection will look the same on all engines just in a different location. If you attach a test guage the pressure should be between 45 and 55 PSI at idle it should hold for a short time after the engine and fuel pump is turned off.

As for the fuel pump it can be accessed through a panel in the trunk. Usually toward the front of the trunk under the carpet. Remove the panel and the fuel pump should be right under it. You will need a special tool, available at most parts stores to remove the fuel lines.

The fuel pump is much harder to replace than the regulator. I will need to know which engine you have in order to give you instructions on changing the FPR. It is not hard to change regardless of which engine you have.

What size engine to you have? If you have a 3.8 the FPR is on the drivers side on the front of the engine. Remove the engine cover and the FPR looks like a small round can with a vacuum hose on the top. On the fuel rail there should be a shrader fitting that you can attach a fuel pressure guage to the rail. It looks like a tire valve. The connection will look the same on all engines just in a different location. If you attach a test guage the pressure should be between 45 and 55 PSI at idle it should hold for a short time after the engine and fuel pump is turned off.

As for the fuel pump it can be accessed through a panel in the trunk. Usually toward the front of the trunk under the carpet. Remove the panel and the fuel pump should be right under it. You will need a special tool, available at most parts stores to remove the fuel lines.

The fuel pump is much harder to replace than the regulator. I will need to know which engine you have in order to give you instructions on changing the FPR. It is not hard to change regardless of which engine you have.

GP Dad - the engine is a V6 - 3100 SFI. This is what is on top of the engine.
Your input is appreciated regarding direction in diagnosing the problem and changing out the parts.

On the 3100 you will need to remove the phlenum from the top of the engine to get to the FPR. It should be located in the center of the engine between the fuel rails. It needs to be unbolted to be replaced. You should be able to check the fuel pressure by finding the fuel rail above the injectors and connecting the fuel pressure guage to the shrader fitting on the rail.

On the 3100 you will need to remove the phlenum from the top of the engine to get to the FPR. It should be located in the center of the engine between the fuel rails. It needs to be unbolted to be replaced. You should be able to check the fuel pressure by finding the fuel rail above the injectors and connecting the fuel pressure guage to the shrader fitting on the rail.

I'm grateful for these entries because I'm going through the same problems on my 02 GT 3.8 L. Maybe you can help me with a side question that's come up while researching. I cannot find (even on the net) a Chilton or Haynes repair manual for the 02 Grand Prix. Do you have any ideas on obtaining one, GTP Dad?? Thanks a ton.

I'm grateful for these entries because I'm going through the same problems on my 02 GT 3.8 L. Maybe you can help me with a side question that's come up while researching. I cannot find (even on the net) a Chilton or Haynes repair manual for the 02 Grand Prix. Do you have any ideas on obtaining one, GTP Dad?? Thanks a ton.


You can find the manual at Discount Auto.......Also we did change out the fuel pressure regulator and it seems to have solved the problem....the car appears to start easier than before.....The part was found at the dealer for $65....Also we were able to access it without removing the phlenum....it took about 30minutes start to finish!!!

Thanks!

I tested my fuel reg. and it was fine. Looks like mine is going to be the fuel filter. My mechanic says that GM did not make a doorway through the trunk so I have to remove the gas tank. Don't think I'll be able to take part in the $65 or the 30min. deal!!! Thanks!

I meant the fuel pump!! (If only it could be the filter.)

If I were you I would check the trunk to see if there is an access panel. The later model Grand Prix's have a panel under the carpet in the trunk to allow access to the fuel pump. I would certainly check before dropping the tank because I think your mechanic is wrong!

If I were you I would check the trunk to see if there is an access panel. The later model Grand Prix's have a panel under the carpet in the trunk to allow access to the fuel pump. I would certainly check before dropping the tank because I think your mechanic is wrong!

Actually, I started to do just that last night but the wife stopped me by telling me she had the trunk full of stuff she had just bought for her office. But, I definitely will check it because there's a big cost savings for me if it is there as I will do the job myself. Thanks GTP Dad!

Actually, I started to do just that last night but the wife stopped me by telling me she had the trunk full of stuff she had just bought for her office. But, I definitely will check it because there's a big cost savings for me if it is there as I will do the job myself. Thanks GTP Dad!


GTP Dad is right, there is a panel under the carpet in the trunk. The dealer price on a new fuel pump assembly was about 400- 450. But Discount auto will sell the pump only for about $150(I think). Good Luck!

Okay, what is the link for "Discount Auto"? I've tried to find them with no luck. I'm glad to hear about the trunk panel. Now, if I could just get my wife to bring the car back!!! Thanks.

Okay, what is the link for "Discount Auto"? I've tried to find them with no luck. I'm glad to hear about the trunk panel. Now, if I could just get my wife to bring the car back!!! Thanks.
Look for Advanced Discount Auto..........they are a big in the southeast!

I think I found the access panel, but it sure is confusing.
There are seven fasteners which look like nuts on bolts. The problem is, the bolt heads appear to be under the trunk which would mean I'd have to get to them fron underneath the car. Am I missing something? Thanks.

These are nuts that can be removed. The bolts are permanently mounted. Remove them and lift the access panel. The pump should be underneath. You will need special fuel line connection removal tools. These can be purchased at a local parts store. Remove the locking ring and then lift the pump out. Be very careful since you are dealing with gasoline. I would use a brass drift on the ring not anything metallic. Also make sure that the battery is disconnected before you start.

Yeh, I thought about the fact that the bolts were permanent later. Thanks for the warning about the ring.
What you're calling the brasss drift, what is that exactly? Is it another component of a special tool to remove the ring? Thanks again!

No it is just a punch made of brass. It will not cause a spark when hitting steel. They are relatively inexpensive at most places that sell tools or hardware.