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  #16  
Old 11-11-2001, 09:44 PM
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Gunter:
Yes, that helps somewhat.
I would now begin to suspect possibly the frequency valve. The warm up compensator I don't believe would actually make the engine stop running due to rich mixture, possibly just make the engine idle too fast. But the frequency valve can really "foul" things up.
I would check that with the fuel pump running you also have battery voltage to the frequency valve. The frequency valve is on the drivers side of the intake manifold next to the air intake for the throttle body. The power supply wire to the frequncy valve is black with a red stripe and white dashes, or possibly on a 80 it's black with a red stripe and white stripe. This is fed, as I mentioned, from the fuel pump relay, socket 1 on the connector. Next I would check for continuity from the other wire on the frequency valve, brown with a green stripe, back to the CIS control module socket 15. Sould of course be less than 1 ohm resistance. You should also check either end of this wire for a short to ground or power.
The CIS control module provides the ground for the frequency valve. It is critical for the mixture preperation that this is carried out without any outside influences.
If the wiring itself is checking out OK, then what I would suggest doing is making up a test harness for the frequncy valve, ground on one side and the other side tap to an underhood voltage source (or just use a second 12 volt battery) to see if the frquency valve can be heard and/or felt to pulse at all. You of course could try another approach, such as seeing if disconnecting the connector for the frequency valve allows the engine to run with the relay installed.
If I am on the right track, and the wiring seems to be in order, then I would suggest that either the frequency valve or CIS control module is ultimately at fault.
When you go to Germany I would be interested in a small bottle of brandy, Asbach Uralt. Only available in large bottles here, don't "need" that much! I like the little hollow chocolate "brandy bottles" with the Asbach in it, I can get those here in Wisconsin though. I'd like to try it without the chocolate sometime, but don't want to buy a huge bottle of it. Stuff's addictive, I hear.
Gilly
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  #17  
Old 11-11-2001, 10:37 PM
scuba
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Gilly,

Thanks for the advise, I'll try that tomorrow if I have time in-between coming home from work and going to my daughters ball game.
By the way, my car does not have the catalytic converter anymore, I don't know if that makes a difference or not.

When I go to Germany I make sure that you will get a bottle of Asbach, that used to be my dad's favored.

Gunter

Last edited by scuba; 11-11-2001 at 10:46 PM.
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  #18  
Old 11-11-2001, 11:19 PM
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Gunter:
Only if it is convenient for you and you can locate a smallish bottle, like maybe in the US what we would call a pint bottle. I believe this would be in the area of 250ML. It is very good stuff, like cognac. I would enjoy just a little from time to time, I don't need a liter of it. I'm not sure if customs allow it to be brought in. If I were more persitant maybe it I would be able to locate a small bottle of it.
I don't believe the catalytic converter would cause this condition. I also don't believe the O2 sensor would even cause this, it would run in a fixed operating mode, but not so rich that the engine would flood. It would be interesting to see how it runs with the CIS control unit disconnected.
Gilly
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  #19  
Old 11-12-2001, 07:40 PM
scuba
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Angry

Gilly and anybody else who has a brainstorm for me.

I checked both wires from the frequency valve today and the reading was 2,7 ohm resistance, then I tried to start the car with the frequency vale unhooked, but the car would not start. Then I disconnected the CIS control module and the frequency vale, but got the same results. After that I hooked the frequency valve back up and just left the CIS module disconnected and still the same. But when I take the fuel pump relay out, the car starts running again, even with the frequency valve and the CIS control module disconnected.
I also tested the fuel pressure today, and between the warm up regulator and the fuel distributor on the control pressure line, I received a reading of 2,0 bar while starting the car. When I checked the pressure between the fuel distributor and the injector on the first cylinder my reading was 4,2 bar while starting the vehicle.
Are this the right values for my vehicle ?

Gunter
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  #20  
Old 11-13-2001, 12:19 AM
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Gunter:
I don't want to misunderstand again, so I need to get the facts straight:
1. The 2.7 ohm resistence, is this from the power wire at the frequency valve to the #1 socket at the fuel pump relay pin AND also between the control wire at the frequency valve and the CIS control module? Should be closer to 0 to 1 ohm, also unusual they would both be the same reading. If this is the case, disconnect the frequency valve, fuel pump relay and CIS control module and check for a short between the 2 wires at the frquency valve electrical connector.
2. When you say it starts running again with the fuel pump relay removed, you mean only for a short time until the fuel residual pressure is gone?
3. I will try to obtain correct fuel pressure readings for you .
Gilly
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  #21  
Old 11-13-2001, 09:22 AM
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The warm-up pressure is good but the other pressure is not of much use other to say that the pump was running. It does sort of show the injector opening pressure and it tells me that the fuel pump was running at the time as residual pressure (that to which the systems goes instantly when the pump stops) is 3 bar.

The car will run without power to lambda control module, frequency valve, and warm-up regulator. it will not run more than an instant without the fuel pump as the main pressure regulator has a dump valve to instantly drop pressure to the residual value to prevent dieseling. (this pressure is below injector opening pressure - so no injection).

If your car is running with the fuel pump relay removed I would find out where the power is coming from. I suspect you are on the wrong relay or the wrong relay is being used. The fuel pump relay on that model is similarly shaped (to all others) but has 6 pins instead of five if I recall.
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  #22  
Old 11-13-2001, 09:40 AM
scuba
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Thanks for your reply Steve,

My car is only running when I take the fuel pump relay out.
The way it works is, when I turn the ignition on with the fuel pump relay installed, I hear the fuel pump running for a couple of seconds to built up pressure. Then I turn the ignition of, take the relay out and then start the car and it will run for about 10 seconds or so until it runs out of fuel.
With the relay out of my car the fuel pump will not run.
I know this is confusing and I hope I explained myself right.

Thanks

Gunter
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  #23  
Old 11-13-2001, 01:44 PM
scuba
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Question

Hello Gilly, Steve and everybody else who follows this forum,

Today I tested the continuity at the brown with green stripe wire from the frequency vale to the CIS control module socket # 15 and it was 0,9 ohm.
Then I checked the continuity between the black and white wire on the frequency valve and socket # 15, and it was 3,079 ohm.
Next thing I tested was the resistance between socket # 1 and the black and white wire from the frequency valve, it was 0,7 ohm, and the value between # 1 socket and the brown and green wire reads 0 ohm.
Then I made up a wire and connected it between the plus pole at the battery and the male plug where the black and white wire from the frequency valve connects into. when I then hook up ground to the other pole from the frequency valve I can hear a click from the valve, but only one time when I connect ground to it.

Is this the way it supposed to be and is the resistance correct on my wires ?

Thanks for your help everybody.

If I ever get done with this car, I can probably write a book about it.

Gunter
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  #24  
Old 11-13-2001, 05:53 PM
scuba
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By the way,

I also tried to plug the fuel pump relay in during the 10 seconds my engine runs, but as soon as I plug it in my engine dies. Here is what I did; I turn the ignition on to accumulate fuel pressure, then take the fuel pressure relay out and start the engine. As soon as the engine started running, I plugged the relay back into the socket, but as soon as I did my engine died.
Is there any way I can check the fuel pressure relay by itself ?

Thanks for your help.

Gunter
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  #25  
Old 11-13-2001, 07:23 PM
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The testing of the frequency valve circuit is OK, but not necessary. I told you that the engine doesn't need the frequency valve to work.

I'm going yto make a stab at the problem. I say it is a problem either at the C105 connector from the starter or the other end of the black wire going to the upper starter bolt. I am presuming that your total load becomes greater than the circuit can handle. Do you have the ETM 1980. Look on power distribution. The terminal C105 which gathers all the wires from the alternator and starter.

My first test would be to disconnect the load of the frequency valve, the warm-up regulator and the lambda controller. See if the circuit will support the fuel pump alone without opening. The C105 connection is in the front of the LH wheel well. It is a row of four phillips screws bundling the groups of wires attached.

To test this theory properly, one should verify that the battery voltage on this 30 circuit stays stable when the problem exists. Thsi is my theory of what it happening. It can be tested with a volt meter. If I were doing it I would also measure the current in this circuit to see if there is too great a load. My theory hinges on eiither too great a load or too weak a circuit. By pulling down the C105 connection you will drop voltage to ignition and most everything else. The wire dropping vertically supplies the ignition eventually and most everything that isn't going out one of the horizontal outputs from C105 (in the diagram).
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  #26  
Old 11-13-2001, 07:49 PM
scuba
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Thank you Steve,

I'll certainly try your theory.

Do you have any idea as to why the engine cuts off as soon as I plug the relay back in ?

Gunter
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  #27  
Old 11-13-2001, 09:40 PM
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I assume you just don't understand. The fuel pump relay takes power from the connection above. When the relay is in the group of appliances (warm-up reg, freq valve, lambda controller and FUEL PUMP) are turned on.

Since the fuel pump seems to work the circuit obviously does its job. Since none of the appliances are absolutely necessary for running except the fuel pump, it is resonable to figure that none of them are the problem UNLESS their excess cuurent or just normal current causes the connection at C105 to break down. In this case the circuit to the ignition is taken down.

This is my hypothesis, IT MUST be understood to be proven. It is absolutely easy to prove, but you have to understand what I'm saying. If I'm right with this hypothesis no amount of parts will fix it. I am saying that one of those phillips screws is loose. The lead that goes to the ignition must maintain battery voltage to power the ignition. Check it out.

My hypothesis supposes that the pump runs doesn't ever run with the fuel pump relay out, not even while cranking or first turning the key.
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  #28  
Old 11-13-2001, 10:18 PM
scuba
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Steve,

Thank you for your reply, ( and you are right, when it comes to electrical stuff, I'm very novice )
I have checked the 4 Phillips screws and there are all tight and tomorrow I'll test the circuit 30.

Thanks again

Gunter
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  #29  
Old 11-15-2001, 10:23 PM
scuba
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My vehicle is still not running as of today, and so far I haven't found anything wrong with socket # C105.
I checked my oil level today and noticed that the oil on the dip stick was way above the normal range, plus the oil smelt strongly of fuel. I changed my oil and filter about 4 weeks ago and my vehicle run for approximately a total of 10 min, after that,when I changed the oil and filter today I had a total of about 11 quarts of oil and fuel mix in my engine.
Can this be from only trying to start the car for about the last three weeks ?
The compression on the cylinders is between 155 PSI and 168 PSI.

Does anybody has any comments to this.

Thanks in advance.

Gunter
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  #30  
Old 11-18-2001, 08:31 PM
scuba
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Steve and Gilly

Steve and Gilly,

I have had my electrical connections checked out by an electrical engineer and according to the schematics, all my wires are in order and check out the way it should be.

Is there anything else I can check ?

Thanks for your replay

Gunter
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