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this is a 91 302 w/ E40D 4x4 4:10 axles w/ limited slip... its an f-150 with a 36xxx on the 5 digit odometer, but i dont think there are any differences that would change the diagnosis compared to a bronco
we just bought it, so the history is vauge, plus the guy lied about at least 2 things now:doh0715:... so theres no telling what is true.
the idle is at anywhere from 1400- 2000 rpm in park all the time, or around 1100-1400 in gear. this is what we have done so far:
replaced EGR
replaced IAC
cleaned throttle body
replaced MAP
replaced TPS: this is interesting.. when we took the old one off, compared to the pictures on "the ultimate TPS thread" the TPS was on backwards.. meaning flipped 180 degrees. before we replaced it, we did the voltage test and it started at 4 volts, and dropped to .75 volts WOT. so we installed the new one the correct way and re did the voltage test, now it checks out normal, .75 idle - 4 volts WOT. nothing changed about how it runs.. still in the same spot.
sprayed every vaccum line/ joint we could find with brake cleaner, trying to rev the engine and find a vaccum leak but was inconclusive. the idle changes a little (50rpm or less) on its own, if there were leaks they were too small to make a difference..
checked the EGR vaccum regulator, did the test where you unplug the wire harness, and check the vaccum at the egr valve. it did not change the vaccum (which was very weak) at the egr. it is giving code 33 but could either the egr sensor or the egr vaccum regulator cause a high idle?
we have performed the self test several times:
koeo:
33 - egr valve opening not detected
Cont. memory:
334 - DPFE or EVP circuit above the closed limit of 0.67 volts.
128 - MAP sensor vacuum was not greater than 2 in-Hg (7 kPa) during normal vehicle operation.
KOER:
code 4 (engine V8)
411 - Cannot control rpm during KOER low RPM check
412 - Cannot control rpm during KOER high RPM check
truck starts fine everytime, and drives ok, at idle w/ no brakes speed is 35 (and it shifts! :shockedscary)
any ideas on what should be tested next? i will keep searching.
thanks:beer
we just bought it, so the history is vauge, plus the guy lied about at least 2 things now:doh0715:... so theres no telling what is true.
the idle is at anywhere from 1400- 2000 rpm in park all the time, or around 1100-1400 in gear. this is what we have done so far:
replaced EGR
replaced IAC
cleaned throttle body
replaced MAP
replaced TPS: this is interesting.. when we took the old one off, compared to the pictures on "the ultimate TPS thread" the TPS was on backwards.. meaning flipped 180 degrees. before we replaced it, we did the voltage test and it started at 4 volts, and dropped to .75 volts WOT. so we installed the new one the correct way and re did the voltage test, now it checks out normal, .75 idle - 4 volts WOT. nothing changed about how it runs.. still in the same spot.
sprayed every vaccum line/ joint we could find with brake cleaner, trying to rev the engine and find a vaccum leak but was inconclusive. the idle changes a little (50rpm or less) on its own, if there were leaks they were too small to make a difference..
checked the EGR vaccum regulator, did the test where you unplug the wire harness, and check the vaccum at the egr valve. it did not change the vaccum (which was very weak) at the egr. it is giving code 33 but could either the egr sensor or the egr vaccum regulator cause a high idle?
we have performed the self test several times:
koeo:
33 - egr valve opening not detected
Cont. memory:
334 - DPFE or EVP circuit above the closed limit of 0.67 volts.
128 - MAP sensor vacuum was not greater than 2 in-Hg (7 kPa) during normal vehicle operation.
KOER:
code 4 (engine V8)
411 - Cannot control rpm during KOER low RPM check
412 - Cannot control rpm during KOER high RPM check
truck starts fine everytime, and drives ok, at idle w/ no brakes speed is 35 (and it shifts! :shockedscary)
any ideas on what should be tested next? i will keep searching.
thanks:beer