Stumble/miss at 2100 RPM Options

[Rrrockhound]

I've got a pretty persistent stumble or miss around 2100 RPM. She purrs like a cat above and below that, but at that RPM, I get stumbling if I rev in neutral (no load) or a miss if accelerating from a stop. I tried disconnecting the throttle switch to see if it would go away, and it actually got a little worse. I cleaned the throttle switch tracks anyway, but no dice. What say you? Trigger points, maybe? It's a 2.0 D-jet, with new plugs/wires/cap/vacuum lines and Pertronix unit.

[bob174]

May be trigger points. Don't know if you read my post from earlier tonight. I changed those trigger points out as a last effort because everything I had read said they were rarely a problem. It fixed a couple problems on my car. They're expensive though. But I look at it like this--everything on my car was old--difficult to narrow down problem areas that way. I started upgrading/replacing stuff with new things and it helps the diagnostic process. Can you narrow it down to a particular cylinder by pulling one injector wire plug at a time, running it to 2100 and seeing if the stumble is still there? It's going to run like crap with one cylinder not firing, but if it's still has a stumble you'll know that the cylinder you pulled was not the problem. Then it's fuel delivery or ignition on the one that's the problem child. Check the fuel pressure--maybe a bad injector?