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Iceguy
10-03-2013, 10:37 AM
My car started having an issue with the idle. Before the idle would go thru the high / low then after a couple minutes it would settle on 900 and sit & run like a champ. Now it wont stop the high low. I noticed that at the low it acted like it was running out of fuel. I check the fuel system - pulled the pump, checked the hoses, pulled a couple injectors - all looks good. I put it back together and did a road test. It hesitates from a stop, but after it starts moving it run strong. I even got stopped by a police officer, lucky he was a car guy & just gave me a warning. Any one have an idea what I need to be looking at next ?

Bitsyncmaster
10-03-2013, 10:43 AM
If your engine is stock, it should have a constant idle speed of 775 RPM. If you're seeing 900 RPM you have something not working. Most common is the throttle plates are not closing fully or you may have the three brass screws not screwed all the way in.

Iceguy
10-03-2013, 03:13 PM
Thanx Dave- Will check that.

Iceguy
10-03-2013, 05:40 PM
Everything seems to be checking out. I was looking at the micro switch & if I lift the throttle to the open point- it runs good or what sounds right to my ear. Do these go bad, or is this being controlled by the ECU & it has a problem ?

Iceguy
10-03-2013, 05:45 PM
Dave- the 900 is sort of a guess - using the tack on the dash it falls btw 5 & 10 - just a shade toward 10.
If your engine is stock, it should have a constant idle speed of 775 RPM. If you're seeing 900 RPM you have something not working. Most common is the throttle plates are not closing fully or you may have the three brass screws not screwed all the way in.

Bitsyncmaster
10-03-2013, 05:53 PM
My tach is dead on accurate but I'm not sure if all of them are that way.
You can press the idle switch with a tool to see if that was not being pressed enough by the throttle arm (screw).
You can also move the throttle spool, forcing it all the way off to see if you may have a binding throttle cable.
Do all these tests with the warm or hot engine at idle.

Iceguy
10-03-2013, 08:11 PM
Dave, A friend ( who has a repair shop ) ran a few tests when I got the car & he said the gauges were off, that's what I'm going by. As you suggested I drove my car and got it warmed up. But when I got back I had it idling in the driveway and it will sat & idled fine. The tach shows a little over 1/2 way btw 5 & 10. I checked the cables & they seem ok.

Iceguy
10-13-2013, 03:49 PM
Now that I have drove my car a bit, after what I thought I fixed, it runs worse that before. It now acts like it doesn't want to run. Before after I'd get moving it would get up & move. Now I give it gas it shakes and acts like it doesn't want to run at all. I reset the idle to where it was, but now it's worse. It is so bad that when I have it just sitting & running the doors shake.

SBL
10-28-2013, 01:50 AM
Are you anywhere near Tampa?

Iceguy
10-28-2013, 05:25 PM
Hi Steve, I'm in Orlando

SBL
10-28-2013, 11:06 PM
Probably too far to travel. I live on Treasure Island on the Gulf. About 30 miles west of Tampa. I have almost always figured out idle problems, although it can be an iterative process.

Do these few things for fun.
Unplug the computer. Tell us what the idle speed is then.
Same for the o2 sensor.
Are you able to feel the idle speed motor work to try to adjust the idle?
Can you hear the frequency valve buzzing?
What position are the brass screws in?
There are often paint marks on the curb idle screw. Can you put it back where it was from the factory?
Is your mixture control screw available? Let me know and then we can proceed.
It goes without saying, check every vac line that you can. There are some that are not accessible, but check them all. Look ate the vacuum canister. I once saw a crack in that which gave crazy idle problems.
Open and clean the control pressure regulator screen and reassemble.
Is the brass tube ("of agony") termed the Auxiliary Air Pipe in position and is the O ring OK? There is another O ring that is used on a tube from the cold start valve to the air intake. Is it OK?

What about any details of the cars history? Gunk in the gas tank (I had the worse one in history, 3/4 full of thick goo)?

Iceguy
10-29-2013, 05:03 PM
Thanx Steve, I printed out the list & will start checking things out. I know there is no gunk in the gas tank. I pulled the fuel pump a while back when the motor was stopping after 4 min. That ended up being the RPM relay. What I know of the cars history is that it was sold new in Va. sat in a collection until a guy in Sarasota bought it, he passed and I got it from a dealer over there.
And you really aren't that far - when I have an AAA card in my pocket !

Iceguy
10-31-2013, 08:01 PM
I unplugged the computer & RMP went to 1000 for aprox 1 min, then shut down.
I do have the mixture control screw.
I think I've checked vac lines & have not found anything - yet.
Still working down the list.

Iceguy
11-14-2013, 05:57 PM
I think I'm getting closer to my problem. My car is running rich - I can smell it & see the smoke. Could this be a bad cold start valve - or warm up regulator ?

Bitsyncmaster
11-14-2013, 06:46 PM
I think I'm getting closer to my problem. My car is running rich - I can smell it & see the smoke. Could this be a bad cold start valve - or warm up regulator ?

It could be but unless you can get some measurements (primary pressure, control pressure and dwell) everyone will be guessing what is the problem,