Where's my Boost?!

First, i will apologize if this problem has been posted, i couldn't find it by searching. Anyways, my problem started when i went to start my car, it was all ready warm. The car would not idle, would just shake. I had to constantly be on the gas or it would quit. This seemed to be similar to the symptoms of heat soak in the fuel rail. After roughly 30 seconds or so the car was running fine. Then i noticed that i had no boost at all. Step it down, nothing. After awhile, if i would gradually ease into the throttle i would get boost again, but if i got on the throttle slightly fast at all, no boost. I am a noob with these cars (an 89 xr7 AOD) and any help or suggestions would be greatly appreciated. Thanks Guys

Maf

Sounds like your MAF and/or TPS. You should have got'n an MIL. Check codes. Test and clean MAF and check/adjust TPS. There could be other problems, but at least this will get you started. Also, you must reseal your upper and lower IC tubes.

Sorry if the above sounds a bit blunt, I was in a hurry when I posted it (pies in the oven Anyway, the above remarks are just maintenance stuff. At least you'll know they are good to go and can eliminate them from the list of possibilities.

The MAF sensor generally causes lack of rapid RPM development after WOT. The TPS sensor will cause air/fuel mixture to be off as you develop RPMS. The IC tubes leaking will cause loss of boost and mess with air/fuel ratios ta boot. Your example of heat soak in the fuel rail could also fit expanding metal joints on the IC tubes that enlarge with heat, and shrink down when cooler. Keep in mind that if your car is running lean, it will run hotter, so another good reason to make sure the MAF and TPS are working properly. And, like I mentioned above, it could be any number of things other then/or besides what I've listed here. Best to do a little maintenance on the MAF, TPS, and the IC tubes and go from there.

discipled1 said:

Sounds like your MAF and/or TPS. You should have got'n an MIL. Check codes. Test and clean MAF and check/adjust TPS. There could be other problems, but at least this will get you started. Also, you must reseal your upper and lower IC tubes.

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No MIL, but you've given me a good place to start. I took it for a short spin tonight, started up and ran fine, just lack of boost.