Another 2k RPM SC at Idle
 

Hello all, I just wanted to through this out there, because I was trying to find the answer before I fixed the problem. I had just went through my engine, new bearings, rod bolts, chains, new cylinder studs, but rehoned cylinders. I had the injectors gone through by Mr. Injector, he has done a lot of P-Cars for me. Anyways, a week ago, I started it for the first time. Once I got fuel back to the injectors, the car Idled at 2k. The next day, it was idling at 1000 rpms, so I took my daughter for a ride. That was the only and last time it idled that low.
So, the first day when I went to set the timing, I could not get it right with Vac Retard hose off. I put it back on, and thought I got it set right. Well, after driving it, the idle went up to 2k, and would come down if you stabbed the throttle, but then would climb again. I set the air by-pass screw and got it down to 1600 rpms. Why I went for this first is unknown, but maybe from trying to get the timing set. I got out my vac gun, and pulled a vac on the advance and retard side. Retard side would not hold any vac.
I figure that something must have been wrong with the advance and retard part of dist. I got another dizzy off ebay for under $300, which the vac can on these is about $600. Got new one in, and car runs great. This engine was never in this car, the engine is an 81, and car is an 82. Anyways, when I was trying to find info about this, I had only found one post that said anything about the dizzy having an issue.

sounds like it was a vacuum leak to me, did the idle change when you pulled the vacuum line to the dizzy..and did it change when you put it back on? check the vacuum lines first and then check the advance on the distributor before "adjusting" the mixture as this can throw everything off. regards, ben

I did not adjust mixture, just the idle screw, or air by-pass. I had never seen a bad dizzy before. The engine that was in this car was sold, and I got the other guys engine as a core, so I had never seen it run. I figured it did not have a vac leak, because I checked everything very well before installing it back in the car. Plus when I removed the oil cap, RPMs would drop, so it was pulling Vac. After replacing the dizzy, everything works great, and I adjusted to idle back up. Got lucky doing swap, and had the dizzy dead on when I checked with my light. Car runs great now. I think the advance retard ring was moving around. I can move it by hand, and could not with the new one.

I would pop the linkage rod off the throttle body before I tried anything else.

I did that. Also, before I put the engine in the car, I made new bushings for the throttle linkage. I tried to go through the parts that wear on it, and have been slowly getting parts for this car. I have not problems with the car now. I have been out driving it tonight, and it runs great. I know the engine ran in the car it was in, but it had 5 broken studs with only 80k on it. The guy had 2 shops do PPIs on it, and they did not catch the studs until the third shop found 3, but there were 5, 4 on one side. This car has been a pain in my butt, do to one shop cracking all 6 heads, then I had to have Rennsport build a set, Thank you Steve.
Anyways, when the car was idling high, it did it at first fire up, and then after trying to by-pass the retard side of the dizzy, the car would run at 900 RPMs, then the next time, it would rev up to 2K, and then after stabbing the throttle a few times it would drop down, and then creep back up to either 1600 or 2k, but it would go down to 900 after stabbing it a few times. The only thing I can say is I replaced the dizzy, and car runs great. I am still going to have a shop check the injection system, due to my CO machine being dead. I am just happy it is done, because I need to start getting rid of some of these P-Cars I have.