1990 Ford Bronco Engine Idle

1990 FORD BRONCO

300,000 MILES • V8 • 4WD • AUTOMATIC

KSCHIRMAN

MEMBER
2 POSTS

I have a 1990 Ford Bronco with a 5.0L V8 engine & automatic transmission. The vehicle idle's at a very high rpm while in park or neutral. When placed into drive or reverse, the idle drops some.

I have already replaced the IAC valve & map sensor and traced all of the vacuum lines. I have also ran tests to see if the air intake manifold is leaking and everyhitng looks to be mounted correctly.

Any idea's where to go next? Thanks for the help.

Apr 17, 2010 at 5:00 PM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

Did you try spraying carb cleaner or starting fluid on the intake or vacuum lines?

let me know.

Apr 20, 2010 at 10:18 AM

KSCHIRMAN

MEMBER
2 POSTS

Yeah i sprayed carb cleaner everywhere, around the intake, over the vacuum lines, around the canisters, everywhere, nothing changed.

I have pulled the following DTC codes:
KOEO:
Active - 23, 23 (TPS)
History - 11, 11 (Pass)

KOER:
12, 23, 45, 13, 73, 12, 23, 45, 13, 73

Before my first post i had replaced the IAC and MAP due to previous codes. I have ran the voltage tests on the TPS and it appears to be bad, so i'm going to purchase a TPS sensor.

Any thoughts with the KOER codes?

thanks,

Apr 20, 2010 at 10:51 AM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

I question if the tps is going to clear those codes. Replace it and let me know what happens.

Apr 20, 2010 at 11:22 AM

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