84 Duke - Engine chugging with throttle (Page 1/1)
842m4SE MAR 10, 06:34 PM
My 84 Duke has started having an issue lately when driving where it starts and idles just fine, but when I apply throttle it's like it's cutting out for a tiny amount of time constantly, so it shakes and makes little power.
I've taken out the EGR valve and cleaned it out with carb cleaner. I am missing one of it's bolts though, if anyone has a spare I could use it- hope that isn't causing the issue. I've replaced all the vaccum lines, new MAP, O2, IAC, cleaned up coolant temp sensor. Also new plugs, wires, and the distributor cap appears to be clean. Inside of the distributor has surface rust. Spray pattern of the throttle body appears to be normal, don't know the pressure though. Car sat for 23 years so many parts are questionable. Only CEL is Code 45 - Rich exhaust.
Here's a short clip of the issue: https://www.youtube.com/watch?v=Y46igxXp3Bk
Any advice or suggestions would be greatly appreciated, thank you.

[This message has been edited by 842m4SE (edited 03-10-2022).]

theogre MAR 10, 09:11 PM
Check timing. ECM uses base timing from Dist to set actual timing to run the car.
Check ICM mounting screws. They are Grounds for the ICM and ECM. See my Cave, HE Ignition

Cleaning EGR might not help.
unplug and block vac line AND tip on EGR and try again.

If doesn't leak for you to test, EGR on this motor can fail internally and leak.
See my Cave, Vac Leaks

ECM doesn't know about EGR but assumes is working to set timing etc. and when doesn't work can cause weird problems.

New plugs? What type/brand?
Some "Gimmick" "performance" plugs are really crap.

Check engine/trans mounts and "dogbone." crap parts allow engine to move and pull wires or break things.

⚠️ Warning: 84 has many things that are 84 only.
Wiring is one of them and many later diagrams are invalid.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave