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Our problem is, it does not idle. It runs off of the coldstart valve, idles for a few seconds, then dies. With the Air Flow Meter arm propped up a quarter inch, it is able to stay running until you turn the car off. We're getting vacuum from the intake, getting spark and the engine is timed to TDC. If you could help in any way possible, it would be greatly appreciated.


Thanks in advance,

Evan
 

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Our problem is, it does not idle. It runs off of the coldstart valve, idles for a few seconds, then dies. With the Air Flow Meter arm propped up a quarter inch, it is able to stay running until you turn the car off. We're getting vacuum from the intake, getting spark and the engine is timed to TDC. If you could help in any way possible, it would be greatly appreciated.


Thanks in advance,

Evan
While I am not a CIS guru, I will point you to a Great little helper. The SEARCH feature.
I used CIS Cold Start 5th Injector, changed to search entire posts, and got a few hit.
I would also suggest reading the threads from start to finish, as there are troubleshooting steps taken to find the end result.
If you skip to the ends, to read the resolution, you may miss, something that may clue you as to where your issue is.

I know that when you read Tolstoy's War and Piece, you start at the title page...and read the bazillion of pages of carefully worded plot and charactor development. While buying the book, and reading the title page then skipping to the end does officially count as reading the book, you miss the warmth of a carefully crafted dialog. I suppose you could by the Cliff Notes version.

I will direct you to:
http://forums.vwvortex.com/showthre...-Crabbit&highlight=CIS+only+runs+5th+Injector

and

http://forums.vwvortex.com/showthre...injector&highlight=CIS+only+runs+5th+Injector

and

http://forums.vwvortex.com/showthre...-problem&highlight=CIS+only+runs+5th+Injector

These may assist you in your endeavors, until others will add to your post.
 

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Ok, the engine runs when you manually open the air flow plate, Right?

If so, the first thing you need to do is throw everything you think is wrong with the ignition system out the window. That will free up your brain for more CIS stuff.

You need to forget about the fuel pump too, that will free more cells up. While you're there, ignition switch, ground wires, starter, all that stuff, out the window.

Now you are down the the CIS and a lot more space in your head to understand that.

What opens the air flow plate? Air. If the airflow plate is not opening, there is no air present to lift it. PERIOD. DONE.

Why is the air not lifting the plate? Air is a lot like electrons. It's lazy and will find the least resistance. If the engine runs [which it can] and when you manually lift the air plate the engine stays running, then you need to find out why the plate is not moving.

If there are no leaks [which I find difficult to believe since the engine was fine and just died on the road] then there is a slight possibility that the fuel pressures are pushing so much on the lever that the air flow plate cannot lift high enough. A simple idle fuel mixture adjustment may solve that, but that adjustment cannot change while driving.

So a recap, the plate must move when you crank over the engine. If it does not you have an air leak. If it does move, then the mixture may need to be adjusted.

Then of course, you really should check the fuel pressures and adjust them if needed. I just do not think you should go there until you understand how CIS works and you're not there yet.
 

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Symptom sounds like a plugged Control Pressure Regulator causing full system pressure to be applied where a much lower control pressure should be present.

I prefer and recommend fuel pressure testing with a CIS specific fuel pressure test set rather than blindly guessing and tearing things apart or replacing them on a guess.

There are four pressures to test on these cars, system, cold control, warm control and residual.
- - -

Two listings from Harbor Freight.
Both include K Jetronic in their applications lisings but I see no shut off valve pictured, no way to know for sure. Without a shut off valve there's no practical way to test system pressure.
That the car runs with the sensor plate manually raised indicates that the system pressure is adequate. That's no substitute for an actual measurement.

http://www.harborfreight.com/master-fuel-injection-pressure-test-kit-97706.html

http://www.harborfreight.com/master-fuel-injection-pressure-test-kit-62788.html

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Then too, and as much as I enjoy disagreeing with Butcher, the car may have a massive intake air leak as he suggests.

First look and see if the idle air bypass screw is in place on the back side of the throttle body.

Look at and feel up the Auxiliary Air Regulator AND all it's connecting hoses, failures there are somewhat common.

Completely remove the main intake air duct between the sensor plate and the throttle body.
Hold it up to a light as you flex it in all directions, shine a bright flashlight inside as you flex it again.
You're looking for through cracks here.
It's old, likely stiff, especially if sitting in a cold Michigan garage, take care you don't damage it as you flex.




.
 

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Symptom sounds like a plugged Control Pressure Regulator causing full system pressure to be applied where a much lower control pressure should be present.

I prefer and recommend fuel pressure testing with a CIS specific fuel pressure test set rather than blindly guessing and tearing things apart or replacing them on a guess.

There are four pressures to test on these cars, system, cold control, warm control and residual.
- - -

Two listings from Harbor Freight.
Both include K Jetronic in their applications lisings but I see no shut off valve pictured, no way to know for sure. Without a shut off valve there's no practical way to test system pressure.
That the car runs with the sensor plate manually raised indicates that the system pressure is adequate. That's no substitute for an actual measurement.

http://www.harborfreight.com/master-fuel-injection-pressure-test-kit-97706.html

http://www.harborfreight.com/master-fuel-injection-pressure-test-kit-62788.html

- - -
Then too, and as much as I enjoy disagreeing with Butcher, the car may have a massive intake air leak as he suggests.

First look and see if the idle air bypass screw is in place on the back side of the throttle body.

Look at and feel up the Auxiliary Air Regulator AND all it's connecting hoses, failures there are somewhat common.

Completely remove the main intake air duct between the sensor plate and the throttle body.
Hold it up to a light as you flex it in all directions, shine a bright flashlight inside as you flex it again.
You're looking for through cracks here.
It's old, likely stiff, especially if sitting in a cold Michigan garage, take care you don't damage it as you flex.




.
A hair dryer,blowing air through it warms cold rubber, and or hot water..... would allow it to bend easier than cold.
 
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