89 GT stumbles 2500 and above

Dtambs39

Member
Feb 25, 2021
23
2
13
50
Dallas
Good to hear the TPS was a big help.
Something else I'd check that is often overlooked is a little something called the MAP sensor. Manifold Absolute Pressure. Should be high on the firewall, just passenger's side of center, a black box about 1 1/2in wide, and 3in tall. Should have a couple wires and a vacuum line coming out the bottom of it. May not be it, but it's worth a look anyway.
Couldn't hurt to take the EGR valve off and clean it out real good with carb and choke cleaner.
Ok I will look for the map sensor. The entire egr is new. I also did the computer test on the egr and it passed. Will keep you posted.
Thanks
I had 39-40 psi in mind with the line disconnected blocked, and varying with the line hooked up at idle. 10-12 extra psi sure will not help it run right. The aftermarket regulator I have is adjustable through the vac port. I think the stock ones are, too, but it’s been a long time since I had a stock one.
I am looking at an aftermarket one currently. Keep you posted
Thanks
 
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HemiRick

I'd be looking at jacking under the house
Jun 28, 2020
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Memphis TN
Mass air cars do not have a MAP they have a BAP, only diff is no hose from intake attached to it. the BAP just senses air pressure at start.
 

Dtambs39

Member
Feb 25, 2021
23
2
13
50
Dallas
I replaced the FPR and set it stock settings, stopped the fuel smell, still have a stumble at 2500 and above. MAF or TFI next? any thoughts?
 

Boostedpimp

15 Year Member
May 8, 2003
1,211
445
124
NJ
I would swap in a new ignition coil to test or find a friend locally with a fox that doesn't have problems and barrow his coil for a drive around the block.