Rough idle all of the sudden - any ideas?
I am hitting the wall trying to find the root cause of a rough idle problem that recently surfaced about a week ago and could use any thoughts you have on what else to look for. It starts fine and was idling great previously. Now the motor really jumps around during idle (set to 980 RPM)...sometimes smooth, sometimes really rough, most of the time rough. No codes were thrown during or after the problem.
05' RK - 510 chain drive cams (06-07 cam plate design), high compression SE 103 top end, T-Max, closed-loop with 2 sensors. I do all of my own wrenching.
Here's my list -
1. Broken front motor mount? - Replaced with new mount; no improvement...
2. Manifold vacuum leak? - sprayed around the seals with engine starter and detected no RPM changes
3. IAC motor not moving? - pulled the air cleaner and watched the plunger move when initializing the start switch...don't know if it moved as much as it is supposed to...or is intermittent...closed the small air port with my finger and the RPM dropped instantly indicating that the port was open as it is supposed to be..
4. Leaking injector? - oberved down the bore of the throttle body while turning the fuel pump (the systems) on and off 5 times...observed no fuel flow into the throttle body...
5. Connector or wire issue? - Pulled the tank and checked the wiring and plug ends on all the TB sensors...observed no issues
6. Loose push rod? - Checked all (SE easy adjustables) and they are tight.
7. Plugged air filter? - No. It is fine..
Any ideas on what else I should check or what may be causing this? THANKS!
"You are only young once but you can stay immature forever"
05' FLHRCI - Black Cherry Pearl - 117" build...125/125 SAE...DTFBY!...