Hatterasman

I have a bad miss in the V8q. The idle is uneven and shakes the car. There is little power when driving and the car seems to shudder, especially when it shifts into overdrive. DTC codes are 2111,2341 and 2413. I cleared the codes and it sets them repeatedly. I removed the RPM sensor and did the ohmmeter checks described on Bentley page 28-80-1. The sensor seems to check out OK. Calls for the sensor to read approx. 1000 ohms across terminals 1 and 2, I get 968 and the other two checks are open as required. What next? Can I check the wiring as described without having the VAG test box? Where do I find the control module harness connector pictured on page 28-80-2? Should I just replace the RPM sensor?

Jeff
`91 V8q

audiqv8

Did this problem just started out of nowhere?

The other two codes (2341 and 2413) indicates that the O2 sensor needs to be replaced. O2 sensor last approx 60,000 miles before they needs to be replaced. I would check the O2 sensor first. Usually when the rpm sensor fails the engine will not start or if the engine was running it will die. Can you rev the engine in neutral? If the engine does not want to rev then I would check for missing teeth on the flywheel. The ECU will throw a RPM sensor error code when the engine does not start. As long as the tach bounce when cranking the engine the rpm sensor should be OK.

Does this happens when the engine is hot or cold?

HTH

Hatterasman

The car has been sitting for several months. I had a little off road adventure with an embankment this winter that required the replacement of the front and rear bumper assemblies. The car drove home OK after this, but then started to miss after I finished the bumper work.

I found the left distributor cap was cracked and replaced them both, feeling sure this was going to correct the problem. It runs a little better with new caps and rotors, but not much.


The O2 sensor is new (<5K miles).

2341 - control limits exceeded
2413 - outside of normal range

I am interpreting these codes to indicate an overly rich condition caused by the miss.

It runs bad all the time - hot or cold.
It starts right up.
The engine can be revved in neutral, it seems to clear up a little if I leave it in third gear and keep the RPMs up.

Jon Clay

maybe a long shot, but make sure the plugs and wires are all connected...

audiqv8

Since you replaced your distributors, check your ignition wire. Is the firing order correct? Are the wires at the correct ohms? Are you getting crossfire? Also check your ignition coil. Do you know why the distributor cracked (arcing)? Pay special attention to the wire going from the coil to the distributor.

Even though the O2 has less than 5k check the wiring, your offroad trip might have damaged the O2 sensor wiring.

Hatterasman

Well, the prize goes to Jeremy from the audifans.com V8 List...I just found #2 and #3 plug wires swapped, duh. To quote my son "Good one Dad, work on cars much?" Car runs great! Codes 2341 and 2111 are gone. Code 2413 is still being set, but that lists as "mixture adaptation problem". I probably just need to drive a while to give the ECU enough information to re-adapt.

Oh, it feels good to on the road again.
Thanks Guys!