GMC Repair: trouble gm, truble, filter 2

Question
1st hi iam a fellow expert in autobody on all experts. i to am a mech. but i am stumpped on 1  
a friend of mine picked up a 1990 carmro rs 5.0
auto . truble is like a old carb system. hit the gas it boggs out. unless you feather it. car did sit for 3 yrs . i have rebuilt the tbi. (pressure reg. tps /iac/ injectors.) changed fuel filter 2 times. mapp sensor 2 times.(note with mapp/mass unplugged it runns fine.) did backpressure test.
checked vac. fuel pressur test. everything checks out ok.. any guess. i am stumpped on it .maybe updated prom.. i don.t have any olisiscope or comp hook up equp. any more . i sold it all on e bay. go figure . thanks  

Answer
Unplugging the TPS causes the fuel system to go to a FULL RICH condition. I would suspect that you have a fuel pressure/volume problem.

Pull the plugs and see if they are or are NOT gas fouled.

Are you POSITIVE that the exhaust is NOT restricted ?.


A revised PROM will not help your problem.





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