I'm trying to track down a "miss" in my '95 964 with 90k miles. It's not real pronounced, but you "suspect" you hear it at idle, and if you rev the engine, you definitely perceive it stumble a little as it first begins to rev up. Once up to 3000-5000 rpm it's smooth. I have replaced the Oil with synthetic and performed an italian tune up, (a couple times: it's fun and it makes people stare at you ;-)), replaced the fuel filter, replaced the spark plugs and examined the wiring leading to the coil packs, (no real defects noted, just some heat discoloration on the insulation), checked the voltage (with the engine running) both at the battery terminals and farther up at the other end of the cables (Identical), and checked/cleaned the air filter. I just now followed the faq instructions to check the fuel and ignition system diagnostic codes. The ignition system wouldn't give any information, the fuel system returned a code 2-3-3. Where can I find out what a 2-3-3 means? It's not in the faq.

Anyone know why the ignition diagnostic system (Port 6) won't talk to me?

How can I troubleshoot the coil packs? My gut says it's an ignition problem. (That or compression, and I don't have a compression tester, and, quite frankly, a compression problem on this engine is more than I wish to face--I don't even want to think about it!)

Rafael mentioned checking the voltage going into the coil packs. What should it be when?

What does the distributor use as a rotation pick-up? Any way to test it?

Sorry for so many questions. I guess I'm seeking guidance on where to go from here. TIA

Bob Neumann

'95 964 90K, '89 745 140K