m20 misifires

[splinn]

Kind of a weird issue, not sure where to begin troubleshooting.

m20 with 170K. New timing belt, new water pump, brand new wires, brand new radiator, brand new fan clutch, valve adjustment. Few other bits. Was running fine untill few days ago when it randomly began to misfire (feels like its running on 3 cylinders).

Cylinders 2,4 & 6 seem to be working OK. Looks like I am getting sparks on 1,3 &6 as well but they are not functioning as they should, when wires from 1,3 &6 are removed from the spark plugs - nothing changes.

Wondering if anyone have dealt with similar issue and what would be the best approach to address this.

Any help on this is appreciated.

[mazzo]

Hmmm....maybe it's time to check distributor cap and rotor + crank sensor?

[splinn]

Thanks will check on those first thing tomorrow.

[RobDog]

This sounds like a injector problem. I believe the injectors are wired in 3's, so that would explain why cylinders 1,3,&6 are not working. I would check power to those injectors 1st.

[jlevie]

+1 on a possible injector problem. It sounds like bank 1 (cyl 1, 3, & 5) aren't firing. A noid light will tell.

[raudonis]

m20 injectors fire in batches 123 and 456.

[splinn]

Quick update
had couple of hours to pull injectors and they are in a horrible shape:





Going to have them cleaned & tested.

What would be the best way to clean the around the injectors without getting any of the dirt in there?