I put in my factory chip. I hope this works!!!!

Alright I replaced my chip with the stock one and it still has the same problem!!!! What should I replace now??

I will try getting a new computer. If the TPS or MAF sensors were broken wouldn't they throw a code?

It would be great to have a scantool on this one, so that you can watch all of the scan data values to see if they are in range or erratic.

I dont think would help though because the dealer used their scanner and couldn't find anything.

What do you think would be more likely to cause the problem, the computer or the TPS sensor? Should I just go ahead and replace the TPS first to see if that works since its alot cheaper that replacing the computer. Or is the computer most likely the problem?

Yes, they'll throw codes. There'* a "voltage too low" code and "voltage too high" code for the TPS (and maybe more codes also) and there'* at least one code for the MAF also.

What kind of fuel pressure are you getting at idle? I had the exact same situation with my Explorer. Would run find at high speeds, but very eratic at idle. It ended up being the fuel pressure regulator. The regulator wasn't maintaining pressure at idle, but then at high RPMs (driving speeds) it was OK becuase it was in a vacuum for fuel feed into the rails.

I have no idea. Would a faulty regulator trow a code?

Doe you think the fuel pressure reg. is more likely to be the cause than the computer?
I personally dont think so because this is an intermitent problem.