[ZTWsquared]

(06-19-2010, 04:32 AM)winnipegkevin Wrote: Looking for input for what direction to take with this situation. This could be a long story, so get a beverage and relax.

I have an '03 SVT. Currently 45k on the odometer. This car has been a real nightmare for me. For the past 3 summers, it has a problem of stalling and dying when the temp gets hot out (28 deg typical, but maybe 24 deg if I drive it a lot over the course of the day). It happens about 5 to 8 times a summer, almost always on the way home from work. Luckily, many times it has happened very close to home, so I can limp it home slowly or leave it and go back and get it later, when it cools down. It will do with stop and go traffic or clear roads.

It has gone to 2 dealers and one garage. Both dealers said they believed it was the fuel pump, but could not replicate the issue. The 2nd dealer changed the fuel pump and fuel filter. Did not work. The 2nd dealer looked at it numerous times after that and could never find a cause. Suggested I get another new fuel pump installed, which I never did.

The MAF was replaced along with the O2 sensors.

The tech at the garage that I have taken it to lately, says it appears to be running lean, which is overheating things and the car is shutting down. The fan resistor, and coolant temp sensor were changed and several cooling fan relays. No change. The latest work was done when I had the car towed in to the shop and they could hear it running poorly. He believed the timing could be off, and found that the spring in the intake gear for the VCT was not functioning properly. Ordered parts and 3 weeks later the car was back on the road. Driveability improved in most regards but 3 days later it died again. It is going back in Monday for more investigation.

Options:
1. Keep dumping money into it to find the cause of the problem. This has not worked so far.
2. Save it for a winter car, when it drives fine due to temp and find a new summer ride. My wife does not like this idea due to storage space.
3. Trade it in at the dealership when it is cooler out. I don't like this option, because I don't want it to become another persons problem.
4. Wrap it around a pole or burn it and hope for insurance money.
5. Sell it for cheap and let someone with more knowledge, money or patience try to fix it.

The car has STS, ORP, formerly SRI, and Xcal2 tune (most recent from FocusSport). I believe the first 3 parts went on after the car started acting up. I believe the first Xcal2 flash was done before the problem started.

I love the car, but this one has really killed my interest. So, what would you do? What option do you like? What would you suspect to be the problem? Things to check?

Thanks for any input,

Kevin

A couple of things stand out for me from your description:

Why were the fan relays replaced ... it seems to me either the fans work (no replacement needed) or they don't >>> time to investigate further.

You didn't say whether or not the fans were coming on at the proper temp (especially the high speed fan) ... but double check the parameters on your tune to make sure the "high speed fan" temp wasn't inadvertently set too high --- and of course, putting the tune back to stock would be a good investigative tool as well ... just to eliminate the possibility that the condition is caused by the tune.

Also: I didn't read anywhere about any investigation into the mechanical side of the cooling ... the water pump, t-stat, rad etc ... are you sure you're getting good circulation.

If you were experiencing a lean condition serious enough to do what you describe ... for sure you would get a DTC related to head temps and your car might even go into limp mode ... or is it limp mode your describing as poor driveability ... in any event, limp mode is always accompanied by a DTC so if you're check engine light didn't come on ... it's either burnt out or you didn't trigger a CEL. You might want to use your x-cal to read codes anyway, just to see if there's anything in the memory.

Good luck.