My Bronc has an intermittent high idle problem when I put the vehicle in park. It does not always do it, but it often idles steadily anwhere from 1,000-1,500 rpm when placed in park after driving. Sometimes tapping the pedal will bring it down and sometimes not. Most of the usual suspects, such as the IAC, are relatively new. The thermostat is a Ford oem and new as well. My temp gauge stopped working if that means anything, although I've pretty much determined that it is the actual gauge itself and not the sending unit.
thanks
__________________ 1990 Bronco XLT two-tone grey and black.
351 5.8 liter, E4OD automatic trans.
Loaded. Most, if not all, XLT options.
146K miles and counting!
Sounds like the high idle kick down deal. When the vehicle starts it starts on a higher rev until.. i.e choke opens or whatever Fuel injected does.. I know it has a temp switch on top of throttle body which tells it when to kick down the idle.. possibly the problem. There is a 2 wire plug that plugs into this.. try a jump wire in between to eliminate the high idle.
Sounds like the high idle kick down deal. When the vehicle starts it starts on a higher rev until.. i.e choke opens or whatever Fuel injected does.. I know it has a temp switch on top of throttle body which tells it when to kick down the idle.. possibly the problem. There is a 2 wire plug that plugs into this.. try a jump wire in between to eliminate the high idle.
Can you tell me specifically where this sensor is on the TB? I have not replaced that one, only the IAC which cured a similar issue a couple of years ago (not exactly the same issue as this and not that many miles between then and now, maybe 1,000 miles.
thanks
__________________ 1990 Bronco XLT two-tone grey and black.
351 5.8 liter, E4OD automatic trans.
Loaded. Most, if not all, XLT options.
146K miles and counting!
There is no temp. sensor on the throttle body or any mechanical "kick-down" on an EFI engine. Idle is solely controlled by the computer. Intermittent high idle would/could be caused by a couple things but the simple and more likely issue would be vacuum leaks. Considering they are intermittent, check the vacuum lines that run from the TAB and TAD solenoids (next to the ignition coil) and behind the engine to the diverter valve (between the right valve cover and the fire wall) and the EGR valve (right side of the engine near the front). These two components are supplied vacuum at variable (intermittent) times during engine operation by the TAB and TAD solenoids.
The other possibility could be TP sensor beginning to die but I'd check the vacuum situation first.
__________________ Only stupid question is the one you don't ask.
1993 Bronco XLT 5.0, E4OD (at the moment)
1992 F-150 XLT 4.9, M5 (at the moment)
Thanks GS. But it seems like a few squirts of throttle body cleaner took care of the problem. I violated my own rule of starting with the simple things!
__________________ 1990 Bronco XLT two-tone grey and black.
351 5.8 liter, E4OD automatic trans.
Loaded. Most, if not all, XLT options.
146K miles and counting!
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.
