1993 Ford Bronco high idle

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1993 FORD BRONCO
100,000 MILES

This thing started idling @ 1500 rpm. No engine light. My scanner wont connect with ecm. So I changed the iac. No change. I disconnected the air charge temp sensor, idle changed for a second then went back to 1500 rpm. I replaced it and pcv. Still 1500 rpm.

Wednesday, October 23rd, 2013 AT 4:54 PM

6 Replies

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Have you checked for vacuum leaks?

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Wednesday, October 23rd, 2013 AT 5:43 PM

CJ MEDEVAC

MECHANIC
11,004 POSTS

IS THE THROTTLE PLATE CLOSING ALL OF THE WAY. POSSIBLE CABLE PROBLEM?

THE MEDIC

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Wednesday, October 23rd, 2013 AT 6:10 PM

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Capped off all vacuum lines. Throttle cable is unhooked. Plates are closed. I noticed iac valve is cracked open so I plugged the port off w/ my finger and still has the high idle.

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Wednesday, October 23rd, 2013 AT 6:52 PM

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Im thinking the computer. After checking into a new one im finding this computer has the calif emissions. Since im in Michigan could I change it to fed emission computer? Calif # are bsb and bsa fed # are cc and cb. Let me know

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Wednesday, October 23rd, 2013 AT 7:21 PM

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Your car is designed to use that computer. If you disconnect the IAC does it make a difference? Also, if you remove the IAC and have a helper turn the key from on to off, can you see the pintel move on the IAC?

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Thursday, October 24th, 2013 AT 6:04 AM

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Disconnected the iac no change, I blocked off pcv and throttle body and discovered a vacuum in the crankcase? Is that normal? I don't think so/////////

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Thursday, October 24th, 2013 AT 6:58 AM