You all have helped me out a ton so far. I've almost gotten my car running the way I want it. First of all, it should be noted that I have replaced all my vacuum lines. I have tried to test all the mechanical components, and I have yet to find my idling problem. I have NOT gotten my mixture tested by a CO analyzer. I have also had a shop clean my injectors. They said one of them has a lower flow rate than the other three, but it "should be okay".

Anyway, on to the problem. It idles too low when cold, and I don't know why. Let me describe what I know.

1. From dead cold (overnight), the car will immediately start, with an idle that barely registers on the tach.

2. When I give it a touch of gas, it will immediately idle at about 1,500 RPM.

3. After about 60 seconds, the idle drops to barely registering on the tach again. The car never dies, but it feels like it's about 50 RPM before it would.

4. As the car warms up, the idle will slowly rise to about 900 RPM.

5. When the car is hot (at least 15 minutes of running), the car will over-run if I turn it off as normal. However, if I turn the key off very slowly, it doesn't seem to do it.

6. When I re-start the car after a few minutes of sitting, the car will return to an extremely low idle until I get going a few miles down the road.

I have read thoroughly through PBanders D-Jet website, and I think I understand most of what's happening in the fuel injection. Most of what I've read says that vacuum leaks will cause a high idle, not a low idle. I guess I still need some guidance. Any ideas?

Have you verified the operation of your auxiliary air valve?

Also make sure your cold start valve is not dumping excess fuel into the engine.

Check fuel pressure also.

I resisted getting a air fuel gauge for a while but it is well worth the $150 in time when you are trouble shooting.

A low idle could be timing.

Fuel pressure and timing are good. I know the AAR closes. I have taken it out and applied 12V. It takes about 5 or 6 minutes to close. I kind of suspect the CSV, but they're NLA. When I apply 12V, it does click, but I don't know if it's leaking. Any recommendations on an air/fuel gauge to buy?

Sure it closes, but does it open back up? When the problem is occurring pull the hose from the AAR where it attaches to the air filter and cover it with your thumb, see if you can feel the suction, or if it changes the idle anymore. If it is occasionally sticking in the closed position it would cause this.

If the CSV is leaking you may be able to get by just with deleting it (route the fuel lines around it) May make it slightly harder to start but wont mess with your idle once its started.

These AEM gauges work well.....http://www.tangerineracing.com/engine.htm
It doesn't sound like an CSV issue to me.....I would look at the AAR again to make sure it does open all the way. How is your distributor? Are the points plates moving freely? A gunked up dizzy may cause weird issues to happen.....not sure if it would specifically cause this issue but check it anyway. You can always bypass the CSV to rule it out.

That is what I have in mine.

+1 on the not the csv. It sounds like a temp problem. Unplug the ts-1, the temp sensor that's screwed into the plenum and see if that makes a diff. Has the tps been adjusted? Is it a 1.7 or a 2.

You may also want to check your tps calibration. I know my car had a very weak speratic idle until I calibrated mine. Now when its warm its a 900 and stays there.

Timing and dirty distributor advance plates.
Explains quite a few symptoms.

sorry, your timing is not right.
I know you stated above that it is right, but its not.

I am starting to sound like Krusty now....geez.
Rich

Rich is right. I didn't think about"overrun" in the sense of dieseling. Timing. Have you readjusted dwell recently? Remember, a dwell change creates a timing change too. Reset the dwell then the timing.

Dwell is critical and so easy to check. It can have a big impact on performance. Check that and then timing.

I will try to check the dwell and timing again this weekend. Curt, we checked the dwell/timing while you were here. I haven't messed with it since, though I did finally get those valves adjusted. Would that have changed the timing that much?

As for the TPS, I think I adjusted it correctly when I put everything back together, but I feel like I might need to buy that circuit board. Mine is a 1.7.

Dwell degrades over time from wear on the rub block. As the dwell changes 2 degrees, the timing changes 1 degree. I hope I got that the right way. Timing could be way off. The car will run with a dwell of 30 or 65, though just barely. A dwell off 30 would equate to the timing being off by 7 or 8 degrees. A worn diz shaft can eat points pretty quickly too. Returning dwell to the desired 47° well get timing real close again.

So, you changed the timing and the TPS....

Ok,

The TPS is NOT a tunable item.
It has the ability to adjust it but that is because the same part was used in many cars, but it is not meant to be changed in your car.

There are what....21 clicks, but more important, and more relevant to your issue, there is a specific idle circuit that you may have adjusted out of the loop.

Search here, I have posted a pic about 30 times of what is should look like when properly adjusted....once you see it, it all makes sense that you cannot use that TPS to tune anything, it only can get worse.

If you remove the cover and take a look, you will see there are a large number of fingers that get touched during the opening of the throttle.

Then close it...the contact MUST sit on one lone single tab at the bottom...and you cannot doing around with that, it just has to sit on that contact to make the idle circuit work properly.

That mis adjusted, and timing and dwell will fix all the symptoms you have described.

Hey, take a look at this pic.
Look at your TPS.
It may not be exactly the same version, but the same condition exists at Idle.

Look at the arrow and how that middle contact touches nothing...
that activates the idle circuit.

you can plainly see that that is no adjustment at all that can be done and you must mount it so that at idle it is exactly in that position....or else it just won't work.