Engine revving issues!!!!
Hall Of Fame
Joined: Jun 2005
Posts: 14,228
Likes: 19
From: Riverton, UT
Magic<----- I was talking about Jmill75 question.
You know, I see 4 seporate issues JUST in this thread.
Magic;
Have you replaced your TPS or used a multi-meter to ensure it is not the TPS?
Don't know of a quick way to test the MAP?
And finally for the return spring, get an old medium spring and hook it up to the bottom of the throttle Cam and string it to the throttle cable mount. This way you get more strength turning the Cam back to the closed position. If this fixes the issue then simply replace the throttle spring, if not I would move to the TPS or IAC.
You know, I see 4 seporate issues JUST in this thread.
Magic;
Have you replaced your TPS or used a multi-meter to ensure it is not the TPS?
Don't know of a quick way to test the MAP?
And finally for the return spring, get an old medium spring and hook it up to the bottom of the throttle Cam and string it to the throttle cable mount. This way you get more strength turning the Cam back to the closed position. If this fixes the issue then simply replace the throttle spring, if not I would move to the TPS or IAC.
All Star
Joined: Dec 2006
Posts: 950
Likes: 0
From: MINNEAPOLIS, MN
Hydra, TPS AND IACV Both r/r...Even fell for dealer TPS and IACV.
Return spring.... cleaned with throttle body cleaner and WD40...seems to work so far.
MAP. Removed/Cleaned/Reinstalled sprayed T/B cleaner in housing on engine side and MAP sensor housing....Again seems to work so far.
Return spring.... cleaned with throttle body cleaner and WD40...seems to work so far.
MAP. Removed/Cleaned/Reinstalled sprayed T/B cleaner in housing on engine side and MAP sensor housing....Again seems to work so far.
Registered User
Joined: Sep 2012
Posts: 7
Likes: 0
I have the same issue. I recently bought a used 2000 Dodge Durango 4x4 with a 4.7 V8.
While driving, the engine will start to race a little and then the tachometer will come back down. I have not identified a specific rhyme or reason for this yet.
I had my mechanic hook up a smoke machine to check for vacuum leaks and we could find nothing.
I replaced the IAC and then reset the computer.
After experiencing the same issues, I took the vehocle to my mechanic who then plugged it up to a scanner and using his tablet, he manually set the idle and some other thresholds.
For a while, all seemed fine, but the idle while in Park is still erratic and the engine keeps throttling up and down when at a steady speed on the highway.
I am reading where this may be a MAP sensor issue, but i am not sure where to look for the MAP sensor, should I simply replace it or only clean it?
Your thoughts are appreciated.
While driving, the engine will start to race a little and then the tachometer will come back down. I have not identified a specific rhyme or reason for this yet.
I had my mechanic hook up a smoke machine to check for vacuum leaks and we could find nothing.
I replaced the IAC and then reset the computer.
After experiencing the same issues, I took the vehocle to my mechanic who then plugged it up to a scanner and using his tablet, he manually set the idle and some other thresholds.
For a while, all seemed fine, but the idle while in Park is still erratic and the engine keeps throttling up and down when at a steady speed on the highway.
I am reading where this may be a MAP sensor issue, but i am not sure where to look for the MAP sensor, should I simply replace it or only clean it?
Your thoughts are appreciated.
Veteran
Joined: Mar 2009
Posts: 426
Likes: 0
From: Mt Airy NC
Wife has a 2001 4.7 and it has the over revving. It has been going on for a few weeks. Not as bad now though from what i understand-nothing been said. I changed the spark plugs with Champion and a few days later cleaned the throttle body with cleaner. This is when it started doing this.