4af pulsing at 2500rpm

[DBguy]

Hey,
I've got a 1989 4af engine that I swapped into a dune buggy. When I pull the throttle up to exactly 2500rpm the engine pulses up and down between 2000-2500rpm. It only does it at 2500rpm and nowhere else. Also you can hear a click going (at the same rate of the pulsing) which I'm pretty sure is one of the fuel solenoid's...Also I'm not sure but the engine may be lacking some power too, not sure though since it's not actually in a regular car...Other than that it runs great, no problems at all...
Any ideas?
Ed

[skyle555]

In my Toyota service manual I located this diagnostic procedure:

Start the engine. Check that the engine runs normally. Disconnect the throttle position switch terminal. Increase the engine speed to 2300 rpm, and check that the engine is fluctuating.
Reconnect the throttle position switch terminal. Again increase the engine speed to 2300 rpm and check that engine operation returns to normal.

This may not be your problem, but it sure is similar.

By the way, this is located under the title "Inspection of deceleration fuel cut system."

[DBguy]

Sounds like the same symptoms for sure...I'll take a look once I get some time.
Thanks!
(if anyone has any other ideas please post them)

[devo]

Check out my thread on location and testing of that switch!
I think im gonna kill myself!

[DBguy]

Thanks devo that's tons of info!
I'm 90% sure that's the problem based on the problems you had and the link that was posted in your thread.
I will try to take a look at it this weekend.
Sweet!