Rough running 3.2

[rokemester]

I’ve searched the forum and there are many excellent no start and rough running threads but I couldn’t find one that lined up with my situation. My engine has been sleeping for 6 months while I did a suspension refresh. I dropped the motor to allow access to troublesome trailing arm to body bolts. While drivetrain was out of car I did the following:
- cleaned up & powder coated engine tin
- adjusted valves
- changed spark plugs
- changed manifold gaskets
- changed oil tensioner gaskets
- changed cap and rotor
- injectors flow tested and cleaned
- disconnected and reconnected DME while the rear sway bar mounts were replaced

Car fires right up but shaking/vibrating at idle. Settles into 800 RPM rough idle. Local experienced wrench advised I check for “dead” cylinders. Once engine was warm I sprayed water on exhaust outlets to heat exchanger. Found cylinders 1 and 5 were cold compared to other 4 cylinders.

Checked for spark at both cylinders and they have spark. Listened to injector 5 vs adjacent 4 injector with stethoscope and it seemed to be pulsing the same. It’s tougher to get to the injectors on the left side of engine with interference from the heater blower assembly.

Any thoughts? Has anyone seen this type of fault before? I’m in over my head here. In my 10 years of ownership the engine has always run well. 175 on the odometer, top end rebuild 11K ago.

[darrin]

check firing order and make sure you didn't swap plug wires for 2 dead cylinders -- (or, nothing to lose by simply swapping the plug wires for those 2 cylinders and seeing if their exhaust manifolds get hot -- they can't get any deader )

[BR-549]

If there are no swapped plug wires, try re-seating the wires on the plugs. I changed my plug wires recently and was getting a very rough idle. I think it was #5 where I had trouble seating the wire to the plug.

[rokemester]

Thanks! When I had a top end rebuild about 12K miles ago I changed out plug wire harness with Clewitt Engineering wire set. The wires are numbered which does help making a mistake. I’ll double check. Funny i had a bit of a fuss getting 5 spark plug wire to seat as well. I kept my old harness. I’m going to try running the old wires to those cylinders and see if anything changes.

My good friend who is a master mechanic on other side of town suggested I shoot starter fluid or carb cleaner into throttle body.

[rokemester]

Took another look. Plug wires 1 and 5 were switched!! Running much better. It is usually operator error with me. I’m trying to retrace my steps and see where I made that mistake. Thanks!

[darrin]

awesome news and thx for reporting back -- enjoy the ride

[rokemester]

Thanks! Now it’s back to sorting through a refreshed front and rear suspension and getting a pro alignment. Hearing some troubling rumbling from the right rear. Hopefully not a trip down another rabbit hole.

[Discseven]

Roke... what's life without another rabbit hole!?

[rokemester]

How true!! It’s what keeps us on our toes. ��