audi-driver1126

i know this may sound like a stupid question but i need to adjust the idle on my 4000s 2.2 l inline 5. last year my dad told me he adjusted the idle because the car was running roughly but that was because i have a very bad leak on the rubber boot on the intake. he made the car idle higher and now that i have fixed the vacuum leak i want to lower the idle back down because its now to high.

is there a certain way to adjust? i am just trying to be safe and not damage my motor

cheers-Aidan

Rogviler

Rest assured that there's really no way to mess up your motor by adjusting the idle. Either the engine will stall or it'll idle really fast.

It is kind of pain to adjust though, because technically you're supposed to unplug the idle stabilizer valve, adjust the idle, then plug the ISV back in. And you inevitably get it dialed in just right and then plug the ISV in and it idles like crap again. I've never had a problem doing minor idle adjustments without unplugging the ISV, but I'll give you the disclaimer that the repair manual tells you to unplug it for whatever reason.

So anyway, the adjustment is done mainly with the flat-head screw on the throttle body. It's at the end of kind of a molded-in stalk right by where the throttle cable connects on the passenger side. Obviously you want the car running while you do it.

At some point I would advance your timing too, but it sounds like it's more important to get the car running good at this point. But advancing the timing will do wonders for these cars. Let me know if you're interested in that. It's easy, it just involves possibly adjusting the idle again and if you want to get really involved, adjusting the fuel mixture (though I didn't do that).

-Rog

audi-driver1126

allright thanks for the help,i was just wondering just in case. and sure i will advance the timing, hows it done?

Rogviler

At the heart of it, advancing the timing is as simple as turning the distributor counter-clockwise. Just loosen the bracket holding it down enough to be able to turn it, and then do your adjustment while the car is running.

Listen for any stumbling or knocking, which would indicate too much advance. Also, it's good to test it out by driving it, especially if you can find some hills to go up. You're looking for an increase in power. Too much advance and it will loose power or possibly even knock. In a perfect world you could run with a high advance and the highest octane gas you could find, but I don't know anyone who has won the lottery enough times to do that on a regular basis. But more octane=knock resistance if you wanted to play with it more.

I run probably a little over 10 degrees advanced on regular gas, and if you really wanted to dial in the frequency valve you could get to 15-20 with no problem. That's almost more trouble than it's worth though, especially if you're not comfortable with doing that (I'm not).

So I would advance the timing and then dial down your idle speed if you need to. Just out of curiosity, what RPM does it idle at right now? Advancing the timing should increase the idle speed, so either way you'll probably have to dial it back.

-Rog

audi-driver1126

allright thanks, sounds easy enough for a 14 year old. at the moment the car is idling at about 1200 rpms but i cannot be sure because i have been fidling around with little things and the car has not been started today. also i shouldnt play with the idle speed or the timing until i replace my exhaust, it has some major leaks. and i could imagine how much that effects the idle and so on.

tommorow i will get the car running, or at least try, and then if i get it to a nice healthy stage i will fill you in on all the little important details. also is it normal for the car to idle up and down between 1000 and 1300 rpm at cold start? it seems mine does that until its warmed up

Rogviler

Well that's not too bad of an idle speed. I consider 1000rpm to be normal for my car, although it seems like some people consider that to be practically out-of-control. I've seen some cars idle at 500rpm, so maybe that is too fast, but it's always worked for me.

As for the bouncing idle, my car does about two revs between 800 and 1200rpm when I first start it, is that what you mean? It's always done that, so again, it's normal to me, but there's probably a way to get it to not do that.

-Rog

audi-driver1126

well when it first starts up the engine revvs up to about 1500 rpms for a second then goes all the way down to about 800 for maybe 3 seconds and then it goes back up to 1200 for 3 seconds continuously for however long it takes to warm up. basically it bounces up and down with 3 second intervals.

and plus, currently the car has little back pressure from the exhaust due to corrosion making fat holes on the pipe, so if the idle is at an ok speed now, it definately will be a little high with a sealed pipe replacement.so basically i need a pipe before i do any of the things on this thread. oh yeah and my father says that if i adjust the timing i will loose fuel consumption too

Rogviler

Heh, I've heard people say that advanced timing will make for worse gas mileage...and just as many that have said retarded timing will do it.

Personally, I haven't noticed anything out of the ordinary as far as gas mileage since I advanced my timing several months ago. So if it does make it worse it's not much. More likely it'll actually improve it (or cancel out any negative effect), since you won't have to mash the pedal down to go up hills and such, which wastes gas.

It would be easy to test though. IF you have a working odometer that is.

As for the idle problem, have you unplugged the idle stabilizer valve's electrical connector to see if it still does that? It won't hurt the car to do that, and it's an easy test.

More likely it's just a result of the incorrect setting on the idle adjustment screw, that'll create that exact problem too. Once you get that dialed in right it should go away. The ISV is expensive to replace ($250 or so for the part), so hope it's not that.

-Rog

audi-driver1126

i think im going to advance the timing, but that will come later. today i tried to start it like i said i would and like many times it only cranks over and doesnt fire. i checked so many things but couldnt find a fault and decided to see if it was getting any fuel and at the fuel distributor there was no pressure what so ever.

got any ideas, this is really putting me off

here is what i tried.

unhook the battery than hook it back up

unplugged ISV and temp sensor

unplugged this thing under the passenger side dashboard, pretty sure its related to the ECU

then plugged it all back in and fired it up

after nothing worked i unplugged the power conectors on the fuel pump and jolted it with 12 volts right on the connectors then hooked it back up and again tried to start it, take a guess what happened...nothing

Rogviler

Do you hear the fuel pump running, or can you get someone to listen for it? It should sound like an angry bee if it's working right. If not, I would suspect something with that circuit. The bad news is there are a lot of seemingly unrelated things involved with that one circuit, like the oxygen sensor, for instance. But the most common things are going to be the fuel pump relay and the Hall sender inside the distributor.

The fuel pump relay is easy, you can pop it apart and look for any loose or cracked solder joints, which is usually what happens. If you have any experience at all with a soldering iron you can fix it as good as new.

The hall sender is harder to diagnose, but more likely I think for an intermittent problem. If you're sure the fuel pump relay is working then that's the next link in the chain basically. If you're not familiar with how it works, the hall sender is what tells the fuel pump relay that the engine is running or trying to run. If it doesn't send a signal then the relay assumes the engine is off so it doesn't come on.

I had a terrible problem with my hall sender that drove me nuts for years. The car would just die while I was driving and then it wouldn't start, I'd jiggle some wires, let it sit, and finally it would start. Then it would be fine for months before coming back. I assumed it was a problem with the fuel pump itself or the relay, but finally I decided to swap the whole distributor (with the hall sender), and it's been fine ever since.

You can replace just the hall sender, which is a disc just inside the distributor itself, but it can be a real pain and you don't really save much by doing that versus the whole distributor, so I'd just pick up the whole distributor. Even one from a junkyard would at least allow you to diagnose that problem for a lot cheaper.

If your fuel pump is coming on, then you're good there. Just start moving down the line, make sure the filter isn't clogged, et cetera.

I think it's awesome that you're starting young trying to fix your own car. I with I had done that, I'd probably be a lot better off.

Also, let me know if you ever need any parts. If I don't have it I'm sure I can get it for you or direct you to someone who does.

-Rog