Emergency help needed

[smurfstiva]

I have an '89 L on carb. Brand new engine. I can not get the thing to idle im talking you start it and it shuts right off. I have check everything i can think of. I have done the carb cleaner trick and only found it increase idle at the base of the carb, i have replaced the gasket under the carb. i have even replaced several what appeared to be somewhat bad vacuum lines. Please help i am at my wits end and if i cant get it running i cant get a job.

[skimsucka]

check the engine fuse in the dash and meter fuse

[smurfstiva]

if i start it and hold the gas down a little bit it will pur like a kitten though

[Lmcclure]

maybe the throttle cable is out of adjustment, if it runs fine with the gas down a little and shuts down when it is let off, thats just my 2 cents

[wybnrml]

Vac advance on the distributor?

[smurfstiva]

i dont think the throttle has an adjustment. and the timing is perfect i can even drive the car but as soon as i push in the clutch and reach for the brake ----------- flat line almost everytime

[Festy46]

As you face the engine from the front of the car, look on the left side of the carb. You should see a plastic knob (it looks almost like a sprocket about the size of a penny). Turn that knob to speed up the engine until it will idle. This will get you going until you have time to locate the problem.

[JohnGunn]

You say that the engine is brand new. By that are we to assume that you have never seen this engine idle correctly? As opposed to its running fine one day and then suddenly it stops running fine.

If that is the case perhaps you need to go back to the basic setting of the idle speed according to whatever manual you have available. Maybe you've already done this, but if so you should report what happened when you did.

John Gunn
Coronado, CA

[smurfstiva]

yes all this has been done what ever you adjust the screw to it will just idle back down to shut off. I have had the timing adjusted perfectly, and it idled like a champ for a few days and then one morning this happened.

[WmWatt]

Theoretically it should be spark, fuel, or air. The engine is too cold for the O2 sensor and computer to kick in. If the fuel line is dirty or the pump is leaking it could be a fuel issue, having to rev the engine to get enough. Perhaps it is an air issue, having to rev the engine to get enough vacuum. A vacuum guage would show if it's a vacuum issue. Did you try misting water or spraying solvent on the hoses while the engine is idling to check for leaks?

[JohnGunn]

Thanks to your responses I think I have a better conception of the current behavior of you car. Here are a few observations, based on that understanding.
1. If your car runs well when you depress the accelerator I would think that sufficient proof that your problem is not with faulty ignition.
2. Also, since it runs with the accelerator pedal depressed, whatever blockage there might be in the fuel system is not complete.
3. Whenever the mechanical fuel pump on my 1967 VW Beetle started to fail, the first sign of failure did not affect the idle. It showed itself initially by not being able to supply sufficient fuel to maintain higher engine speeds.
4. On my Beetle, if the automatic choke was not working properly at start up, it would behave much as you car does.
5. There are two ways you can check if this is your problem. Start the engine and keep it running with the accelerator pedal until the engine is warm. At that point if you remove your foot from the accelerator pedal and the car idles as it should, then you choke is not working. The other way to test the working of the choke is to look at the carburetor. There should be a butterfly valve in the top of the throat of the carb, which should be at least partially closed when the engine is cold. Also that should be connected to a fast idle cam on the outside of the carb which when cold holds the throttle slightly open to provide a faster idle until the car warms up.
6. If the choke checks out, I would start wondering if one of the carburetor jets or passages was clogged. Someone with more knowledge of you system would have to tell you how to test for that.

Waiting for your next response.

John Gunn
Coronado, CA

[NovaSS]

sounds like dirt in an idle passage of the carb, Make sure the PCV valve is working too, and double check vacuum advance is working.

[smurfstiva]

so john your saying the same thing i am that the carb itself is the problem and probably needs to be replaced? and just for curiousties sake what is this vacuum advance i keep hearing about? Thanks again for all your replies

[JohnGunn]

so john your saying the same thing i am that the carb itself is the problem and probably needs to be replaced? and just for curiousties sake what is this vacuum advance i keep hearing about? Thanks again for all your replies

At this point I think it is too soon for me to make any recommendation to you about replacing a specific part. My general preference is to analyze the problem as carefully as I can, trying to think up tests to use in identifying the most likely cause of the problem. It usually turns out to be a lot cheaper to study the problem for a while before you start replacing parts. In addition the process of thinking about a problem is maybe the very best way to learn more about your car. With practice you will get better and better at it and eventually discover that a lot of the same logical processes have direct application in many other areas of your life.

On the other hand, if you are in a hurry and have the money to buy a used carburetor at a junk yard, it might be a good investment. Even if it did not solve your current problem. It might be nice to have it in reserve for when the current carburetor does fail.

NovaSS mentioned a dirty idle passage, which sounds interesting since that would explain why only the idle would be affected. With my VW you could buy a rebuild kit which included the parts that might need to be replaced, and you could take it apart and clean it up. They were pretty cheap. Certainly cheaper than buying a new carburetor. Also, some carburetor problems like the choke problem I wrote about might only need to be lubricated to make them work properly.

In the end, all I can do is tell you what I would do. What you do, or do not do, is completely your decision. I've given long detailed recommendations to people and never heard a word back from them. I figure they wanted someone to tell them the part to replace, but didn't want to spend the time necessary to figure out what part that might be. Sounds like you're leaning in that direction. Which is fine. I just don't have the answer you want, at the moment you want it.

John Gunn
Coronado, CA

[zoe60]

Make sure your slow fuel cut solenoid is getting power. It's wires go to the rectangular plug that the carb is attached to. It is on the driver side of the carb.