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<x-charset iso-8859-1>Sounds like you have pretty much done everything, it's quite possible it's not the fuel injection. Some other things you might want to try. Since you have disconnected the cold start valve electrically also disconnect and plug the fuel line. This will totally isolate the valve and rule it out 100%. if you car runs smooth at idle you found your problem, a leaking cold start valve. If you still have the miss connect a timing light up and run the engine. when you point the timing light at the timing mark the light flash should be consistent and constant. If the flash is intermittent (a miss) you can rule the fuel injection out, the problem is in the ignition system. Check all of the coil connections to ensure they are tight, next run the idle and check the voltage on the hot side of the coil. The voltage should remain constant if it doesn't check the car electrical system. If the voltage is constant at the coil change the distributor condenser and points (if you haven't done so), and check the spark plug wires. If the wire insulation is hard and dry replace the wires. After all of this if the engine still runs rough at idle and the timing light flash isn't consistent, you may have a problem in the distributor. I had a similar problem, after I did all of the things I just listed. I found out my distributor had to much axial and radial play in the rotor shaft and didn't allow the points to not open and close and causing a miss. The miss was more noticeable below 1,000 RPM above that you couldn't notice it but it was still there (use the light). I bought a rebuilt distributor ($60) put it in, and the miss was gone. I hope this helps. Good Luck Jim San Diego > So when I bought the car two years ago the guy pointed out that the MPC to > the cold start valve was intentionally disconnected. Don't connect that, it > floods the engine he said. I happily took his advice while I wondered about > fixing it. Posted to the list and was told either a bad cold start valve or > wires reversed somewhere giving it constant power. Well in my travails > trying to iron out the miss during Idle I came across a spare intake for an > automatic square and switched the cold start valve in....continued to flood > the engine. when I unplugged it the idle improved a bit but still sounded > and felt too rich....fast forward to latest job...fixing the miss. So the > first thing I did was unplug that mpc, as I said it slightly improved the > idle, but still a miss and wanting to stall. > > So I went out and bought a fuel guage per Muir pages 140-143, sliced off the > end and hose clamped it onto the rail test port..pressure reading 32 foot > pounds at idle, adjusted it down to 28 foot pounds by way of the regulator - > okay great! so the idle was missing because the pressure too high and > flooding overrich mixture. > > well I went out and bought another set of bosch supers and screwed out the > old ones..black around the rims slightly wet but reusable - hell only 3 days > old. Put the fresh ones in and fired it up. Still a miss. Hooked up my > tach/dwell and measured the dwell. 49 degrees at idle , moving slightly to > 50 degrees in the higher rpms. okay. tried to set the idle by the adjustment > screw. Now I could make an adjustment from between 800-900 up to 900-1000. > the needle moves evenly between 900 and 1000 during the course of the idle, > low end towards 900 for the miss and back up towards 1000 for the smooth. No > better than that. Took it around the block a few times and then back to the > curb. Idle just as bad missing as ever. read the voltage off the battery at > idle 13.5 even. At mid to high rpms it goes up to 14.0. > > So the dwell & voltage seem okay, now the fuel pressure is at 28 pounds, yet > the idle doesn't quite yet. Miss as solid as if I've done nothing to the > car. I'll buy a new cold start valve and/or check the wires to the starter > but I do not think this will solve my miss. Am I right? Am I wrong? My God, > what have I done? > > Chris > > ------------------------------------------------------------------- > Too much? Digest! mailto:type3-d-request@vwtype3.org Subj=subscribe > </x-charset>