uncontrolled reving

[aviatorCH47]

I just got a 1998 dodge dakota sport v8 5.2, and it revs itself while at highway speeds, also, sometimes there is some sparatic idling at points. There is no change in speed or shifting of the transmission. I had the transmission serviced and a tune-up done but neither fixed the problem. All the mechanics I have talked to about it are freakin clueless and give me little or no help. Would like some help please, at least an idea.

[jimmymc]

engine revs but no change in speed? something must be slipping--have another look at that tranny.

[aviatorCH47]

Originally Posted by jimmymc

engine revs but no change in speed? something must be slipping--have another look at that tranny.

yes, but it even does it during idling sometimes, when at a complete stop

[jimmymc]

When the engine revs up...what would be the estimated rpm change?

[aviatorCH47]

Originally Posted by jimmymc

When the engine revs up...what would be the estimated rpm change?

it revs about 100rpm depending on the speed. When I took it in to the mechanic he said that it may be the idler control sticking? Also, they did clean the fuel injection system and that has seemed to help a bit, but I haven't driven it a distance since then.

[jimmymc]

cleaning the injectors is good...hope that will fix your problem.

surging...

it can be caused by a whole host of things...like lean/rich fuel mixture, bad electrical connection, sparkplug, plug wire.
I would find the MAP sensor and check to port to the outside air pressure...sometimes this gets stopped up by dirt and it confuses the computer on the correct fuel mixture needed.

good luck jimmymc

[bustedratchet]

I don't know if this might help but it is an Idea.About a year ago my buddy at work was looking at a larger Dodge truck with about the same symptoms as yours.After checking it over for a while He found some Dodge trucks have an internal vacuum leak which may cause this. I think he replaced the intake manifold gasket set.