TBI Frustations

[madhatterxlch]

1991 Chevy Blazer K-5, 5.7 TBI OBD 1
From 1 day to the next the truck went to $hit, pardon my french.
The truck would idle fine for a while, then died. I decided to change the fuel filter, didn't fix the problem, so I changed the fuel pump, no change. After some more troubleshooting and the proplem becoming worse and not fine I rebuilt the TBI, replaced the IAC, then the MAP, then the TCS, then checked the EGR and cleaned, then cut out the CAT, then changed the plugs, checked Vacuum lines & grounds, NO CODES on the ECM, checked the coil found to be good, TPS checks out good. HELP!!!!!! About to change my insurance coverage to full coverage and dump a gallon of gas on it and watch it burn.

[gmclowsierra]

check fuel pressure

[oltronj]

try the coolant temp sensor.

[DannyO]

disconnect the o2 sensor and wait until the computer goes to closed loop then it should be fine. Could be a bad o2 sensor. my brother had a 91 caprice that did the same thing. i wired it straight from the computer and bam ran great.