Help needed to diagnose fuel injector problem.
 

My 1989 230E is hesitating because it is not getting any fuel to #3 cylinder. I know this because there is no change in rpm when I pull the spark plug wire on #3 cylinder.

I tried changing the spark plug but there is no change. Then I exchanged the #2 and @3 fuel lines to see if the fuel distibutor was a problem but that also didn't change anything. Now I concluded that it must be a fuel injector problem.

The fuel injector seems to be very loosely installed and it is turning free in both directions. I have no experience on fuel injectors. Should I disconnect the fuel line to the injector and then pull it out to remove it ?

Ok, I'm going to assume this is a CIS-E 102 engine. Remove the 5mm hold down bolt and swap the injector from one cly to another, if the skip moves, theres your problem, if it doesn't. Run compression and leakdown. The seals are nothing but odd shaped orings so the injector will wiggle and spin and such.



I also am assuming you checked for vacuum leaks and so as well.



Joe

As Joe points out, be sure you don't have a vacuum leak into that particular cylinder.

the problem is suddenly gone
 

I don't know how it disappeared but it might be because yesteray I put a bottle of injector cleaner then took the car around town .

Yesterday it ran very bad and then I parked it in the garage. Today there was no hesitation or stalling right at the start.

I forgot to mention on top of the post that the problem appeared suddenly after I let the car rest for 3 days. I usually never let it rest for more than a day.

It was definitely not a spark plug or voltage problem because when I pulled off the connector 1 inch off the spark plug I could hear very loud noise of the spark passing from the connector to the tip of the spark plug.

I may never let my car sit for more than a day again because I am sure the problem will come back if I do so. I only want to drive my Mercedes.