still more problems

[61sktnbug]

ok so i have the head back on the car , adjusted the lifters , it statrs up , runs for about 1-2 seconds then drops off and dies, and if i try to feather it to kepp it running it just missis and farts and coughs , any ideas? i m getting bored of not driving it

[pearldrum]

Is the timing off? Check the reference marks on the cam sprocket and flywheel.

[Porsche944]

Air Flow Meter disconnected?

FYI: The DME will start the engine and then check for a valid signal from the AFM. If the AFM signal is not valid the DME shuts off the injectors, ignition, and fuel pump.

[pokey]

Look at his sig. It's an early 924, not a 944 or 924S. No AFM or DME.

[AFJuvat]

You need to make sure that your mixture is set properly.

Make sure your cold start valve is connected, as well as the warm-up regulator.

Sounds like you are running a little lean. - that 3mm Allen screw next to the fuel distributor - turn it clockwise.

AFJuvat

[61sktnbug]

Originally posted by AFJuvat
You need to make sure that your mixture is set properly.

Make sure your cold start valve is connected, as well as the warm-up regulator.

Sounds like you are running a little lean. - that 3mm Allen screw next to the fuel distributor - turn it clockwise.

AFJuvat

i tried that i didnt make a diffrence , this is going no where fast!

[SoCal Driver]

Originally posted by 61sktnbug
i tried that i didnt make a diffrence , this is going no where fast!

It's an old 924!!! What do you expect miracles???

[AFJuvat]

Originally posted by 61sktnbug
i tried that i didnt make a diffrence , this is going no where fast!

Welcome to Bosch K-Jetronic a.k.a. CIS!

Ok, we are going to go back in time a bit. I'm not trying to insult your intelligence, but CIS is a pain to get dialed in properly, especially when you are dealing with near 30 year old cars.

You've fixed your head - so we are going to make a few assumptions before moving on:

1. The head is installed properly
2. Timing is properly set
3. You used all new gaskets, all vacuum hoses are connected correctly, and in good condition.
4. You have a new fuel filter installed.

If the above do not apply, stop now and correct. All the fixing in the world will not correct for the above.

Now, you are going to need some special tools - yes, they are expensive, but without them, you are pissing into the wind and will get nowhere.

CIS fuel pressure tester. Out host sells one, you can find it here: http://www.pelicanparts.com/catalog/shopcart/PORS/POR_PORS_PTOOLS_pg5.htm#item26

Yes, it is expensive, yes, you need it. No, you can't work around it.

I would assume by now that you have the haynes manual. Read the section on fuel injection, then read it again. Read it again a third time. If there is something you do not understand, post the question here

On to troubleshooting - in the next post....

AFJuvat

[AFJuvat]

1. Remove the rubber boot between the airbox and the sensor plate.

2. Pull your fuel injectors one by one. When the injector is pulled, put the key in the ignition and turn the ignition on - do not start the car. Now, depress the throttle plate, the fuel pump should start running and you should get a good spray out of the injector. After you stop pressing the sensor plate, the fuel pump should stop and after a couple of seconds, the injector should stop flowing and not leak. Repeat for all four injectors. If the injectors do not open, you have a basic fuel pressure problem - check the basics, pump, lines, connections, etc. If you get a bad spray pattern or it leaks, replace the injector. Install all injectors before moving on to the next step.

3. disconnect the coil wire. Remove cold start valve. Leave fuel line and electrical connection connected. Have a friend crank the engine. The cold start valve should spray a fine mist of fuel. If yes, continue, if no, replace.

More in next post

AFJuvat

[AFJuvat]

4. If you have lambda control, locate the frequency valve - it looks like a small cylinder on a fuel line with an electrical connection. When the engine is cranking, it should be buxxing. If it is not, find out why - bad valve, or bad relay - follow procedures outlined in Haynes manual. Look next to your control box - see that funny looking relay - is it clicking? If no, replace.

5. Break out that new fuel pressure gauge that you just bought. follow procedures in haynes manual for ALL fuel pressure tests. All measurements must be within the proper range. Pay particular attention to the tests for the warm-up regulator. A bad WUR will ruin your whole day.

6. Check the pressure regulator on the fuel distributor - it is that allen screw held on with a locknut on the side - it sticks out at a funny angle - you can remove it - watch out, it has springs and shims and o-rings (Oh my!) everything has to be good, clean, no cracks, binding, corrosion, gum, etc. If the regulator is gummy, germove the whole distributor and soak it. DO NOT DROP THE CENTER PLUNGER!!!!! If you scratch it, or damage it in ANY way, you need to replace your distributor.

If all of the above test correctly, and the car still will not run, you need to look at the ignition system.

Basics - do you have spark?

Is the basic distributor timing set properly? Are the vacuum lines connected properly? Cap and rotor in good condition?

Vacuum system: Make sure you have NO vacuum leaks. Clamp the air hose on the auxillary air regulator and see if the car runs easier - if you notice a definate smoothing out of the engine after you clamp the line, replace the AAR.

If all of the above test correctly, you should be able to get the car at least running. If the exhaust is making your eyes water, you are too rich. If the exhaust is very hot very quickly, you are too lean. Use the 3mm allen screw to adjust mixture. Clockwise for rich, counter to lean. You ALWAYS make your last adjustment to rich. You can adjust it close by feel and by ear, you really need a CO meter to get it dialed in properly.

Now adjust your distributor timing with a light.

Any other questions, ask away

best of luck

AFJuvat

[61sktnbug]

Originally posted by SoCal Driver
It's an old 924!!! What do you expect miracles???

no i dont but it ran fine before , so i assume that it would run good once i installed everything the way it was,

thanks for that list af i ll try that today