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89 Lx 5.0 over reving while not under load?

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Old 05-09-2006 | 08:44 PM
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89 Lx 5.0 over reving while not under load?

Hi Guy's
I just joined and like what this site has to offer.
I have just bought the car and on Saturday I did a full tune up with Ford OEM parts however the motor feels like it has a " Miss" and the motor revs up to around 2000 to 2500 RPM when in Park or netural once it's warm and now it it starting to act up while I drive the car it wants to rev while in drive and stopped at a light.
The car is very clean but had a lot of carbon build up as an older lady was driving it.....LOL
Any Idea's ???
I have changed the plug's,wires,cap,rotor. OEM from Dealer
By the way I also checked out the TPS sensor and it looks KINDA new.
Thanks in advance.
TSPROB
Old 05-09-2006 | 10:05 PM
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again with the RPM problems on here...lol....could be a sensor, or maybe the IAC valve (try cleaning this) although if its only doing it when the engine is warm then maybe your looking at a head gasket, see what some of the other guys say but if you want to check your head gasket, spray some WD-40 around the engine close to where the gasket is and see if your engine rev's up....also maybe timing, cause you did replace rotor and cap, so that could be screwy....good luck
Old 05-09-2006 | 10:45 PM
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Reving up

Hey Man
Thanks I will try that.
Take it easy
Rob
Old 05-25-2006 | 02:33 AM
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My car would randomly rev rather high by itself when it got hot a couple of years ago, it was the TPS that was causing it. Hook a multimeter up to it when its doing it and see what the reading is, it shouldn't really be over 1v when the engine is running at idle, if it is (mine was at like 3) then you know the sensor is baffed. Another check on it is to check the voltage on it Engine off, key on, it should read somewhere between .65 and 1.1v (though its nice to keep it below a volt to be safe, 1.2v is percieved as dead by the ECM and will go into limp mode). If it is, start slowly opening the throttle and watch the voltage, it should increase smoothly, if it jumps and bops all over the place then you know the sensor is FUBAR.
Old 05-25-2006 | 08:38 AM
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Still acting UP

I have since changed the IAC & the TPS sensors.....
But it still act's up.....It's driving my NUTZ !!!!!
Any other Idea's ? :2:
Old 05-25-2006 | 09:21 AM
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Take it to a shop and get it looked at.I had a plug that would work fine till I hammered it then the motor went nuts.To drive normal it was fine.10 minutes and the problem cured.Cost a couple of bucks but it was my buddies shop so not to bad.
Old 05-25-2006 | 11:10 AM
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Did you reset the ECM after changing those sensors?
Old 05-25-2006 | 12:50 PM
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Reving Up

Hi Guy's
I have not reset the ECM
However someone said it could be the upper intake gasket.....
I will get someone to check it out
I had a friend at a Ford Dealer hook it to the scanner...But no codes other than the Pollution Pump...thingy....He said every car around this age shows that the pollution pump is bad...so I don't know nor did he.....
Thanks
Rob
Old 05-25-2006 | 12:53 PM
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hey i cant help you with your problems but why dont u get some pics of your ride up.
Old 05-25-2006 | 01:00 PM
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Originally Posted by tsprob
Hi Guy's
I have not reset the ECM
However someone said it could be the upper intake gasket.....
I will get someone to check it out
I had a friend at a Ford Dealer hook it to the scanner...But no codes other than the Pollution Pump...thingy....He said every car around this age shows that the pollution pump is bad...so I don't know nor did he.....
Thanks
Rob
Try resetting the ECM first, just for ***** and grins. And yes, you could have a vacuum leak.........



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