So after removing, rebuilding, and reinstalling the trans in my 92 400E I started 'er up tonight and noticed a miss. In the course of pulling the trans out I removed the airbox so I could unbolt the dipstick tube from the back of the engine. I noticed the wiring harness going to the injectors on the passenger side of the engine wide open, I could see copper (oh joy). So after having my engine rock back and forth whilst R & Ring the tranny, and taking the airbox off and back on again means I could've bumped a wire and caused a problem.

So my question is this; to narrow down which hole isn't firing is it a bad idea to unplug injectors while the engine idles to see which cylinder isn't firing? I don't want to assume it is a harness problem, but I would like to narrow down which cylinder is the culprit so I can check the plug, wire, etc. I don't want to cause more problems by unplugging injectors.

Car ran perfect before I pulled the trans.

No "idiot lights" on the dash are on.

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Fourings

84 Audi Coupe GT with Turbo engine, EFI (buh-bye CIS), Jamex seats, Koni's/H&R's, e-code lights. 210k and counting.
1992 Anthracite 400E, 161k, "Grey Ghost".
1986 VW Quantum Syncro, 192k, gone to the crusher in the sky.
1989 300TE 172k. (Was mine, now also Mom's car)
72 280SE 4.5 (Mom's car)

To start with is the trans body GROUND wire tight??

If so then start with disconnecting the injector wires..you wont damage the computer.

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I'll assume you mean the thick braided ground wire that runs from the subframe on the driver's side to one of the bolts in the bellhousing that holds the tranny to the engine. Yes, that is tight.

Ok, thanks. Not that I have a choice with this engine, but disconnecting injectors is much less exciting that pulling spark plug wires whilst idling. Less excitment in this case is a good thing.

__________________
Fourings

84 Audi Coupe GT with Turbo engine, EFI (buh-bye CIS), Jamex seats, Koni's/H&R's, e-code lights. 210k and counting.
1992 Anthracite 400E, 161k, "Grey Ghost".
1986 VW Quantum Syncro, 192k, gone to the crusher in the sky.
1989 300TE 172k. (Was mine, now also Mom's car)
72 280SE 4.5 (Mom's car)