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  #16  
Old 11-13-2007, 04:11 PM
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Join Date: Nov 2007
Location: Vermont
Posts: 21
HI, Stupid me I may have shorted the wires on the fuel pump when I was replacing the check valve. Is there a fuse or something that can be replaced if the fuel pump were shrted.

Is there a way I can jumped the fuel pump.

Thanks

Aj


Last edited by megatrack; 11-13-2007 at 06:35 PM.
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  #17  
Old 11-13-2007, 11:57 PM
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I found the answer to my last question here by
Uncle Acky
Help Will not start
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  #18  
Old 11-14-2007, 08:38 AM
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Location: Richmond Hill
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AJ, Not stupid you, there is no power to the fuel pumps when engine is not running. I know the engine was off when you changed the check valve.

Please go through the steps in the post you linked above. do this carefully and write down the results so it will be easier to troubleshoot. I suggest you copy and paste the test info into a word document, print it out and bring it to the car with you.

Let us know what you find.
Acky
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  #19  
Old 11-14-2007, 10:43 AM
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HI, Just got done with the test
1- 12.2v
4- ground ok
10-12.1 V ign on
12-9.8v while cranking
16-4.2v while cranking
21-10.9v ign on

I have bridged pin 1 and 2 car started after 2-3 try, RPM very low, Also I have noticed that my rpm do not work.
Is that also related to the MAS?
Thanks for helping Uncle Acky.

AJ

Last edited by megatrack; 11-19-2007 at 03:01 AM.
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  #20  
Old 11-14-2007, 01:32 PM
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Location: Tiki Island Texas
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If this is only when cold it may be just a symptom of age. Recommended fix is to boost fuel distributor lower chamber pressure up to .45 from .4 bar and adjust the idle mixture. Needs to be done in a shop with proper gauge.
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  #21  
Old 11-15-2007, 04:15 PM
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HI AJ,

Your test results look good, the readings are very close to what I get on mine.

With this in order, the MAS unit should power the pumps. If the pumps run and draw 4 to 8 Amps then everything in that circuit is in order. You problem is elswhere.

At this stage I suggest you test and clean the ICV, idle control valve. Check throttle position sensor and throttle valve position switch.

If you can have the fuel preasures checked it would be of great value. Please keep a record of your tests and results.

It is best to test circuits and systems rather than randomly replacing parts.

Regards,
Acky
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  #22  
Old 11-15-2007, 07:28 PM
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HI,
Like I said earlier the pump doesn't work with the MAS in place. it only works when I jumped pin 1 and 2 . So that's why I tough that the MAS was bad. I will check the posts for test procedure on the parts you have suggested.
Thanks AJ
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  #23  
Old 11-16-2007, 07:31 AM
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Sorry AJ,

to the best of my knowledg, from your test results the relay portion of the circuit in the MAS unit is not working.

Replacing the mas unit should fix the problem. I personally would try to use a known good one for confrimation. Also I would carefully open the unit and check it with a 5X magnifying glass, look for cracks in the solder joints, connections and pin connections. It may be repairable.

Please don't waste time now with other components that I suggested, I though you were having hard starting even with the pins jumpered.

Acky

Last edited by Uncle Acky; 11-16-2007 at 09:26 AM.
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  #24  
Old 11-16-2007, 08:18 AM
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Location: Richmond Hill
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PLEASE NOTE:

I see a relationship with the tachometer. Included in the diagrams I will send you.

A wire goes from fuse #5 to the tach (speed sensor?) then to connector #26 (inside fuse box, below fuses) then to pin 11 MAS unit also to pin 27 CISE control. I have not checked this circuit. I will pull fuse 5 in my car and try to start engine to see what it does.

Also I suggest replacing fuse #5, #7, #9, lightly smear silicone grease on the ends first.

I will send you diagrams...e-mail me.
Acky
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  #25  
Old 11-16-2007, 09:12 AM
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Location: Vermont
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HI Acky,
SInce I don't know anyone with a MB I ordered a MAS from ebay, I paid $50 for it.
In the mean time I'll replace the fuses, and cross my fingers

Thanks for helping.

AJ
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  #26  
Old 11-17-2007, 07:34 PM
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HI,
Ok I did receive my MAS, it fixed the fuel pump (I now have power) and tach problem but I still have my cold start problem, so I will check the parts that Uncle Acky has suggested to clean in an earlier post and let you know the results.

Back to square 1.....

AJ

Last edited by megatrack; 11-19-2007 at 02:27 AM.
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  #27  
Old 11-19-2007, 10:18 PM
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Join Date: Nov 2007
Location: Vermont
Posts: 21
HI, I bought a fuel pressure gauge, anyone as a procedure for this testing the fuel pressure.
About adjusting the fuel mixture:
http://www.landiss.com/mixture.htm

I am a little confused about the PART WHERE THEY SAY IT CAN BE ADJUSTED WITH A VOLTMETER.
I tried some today between pin 2 and 3 of x11 and I got 1.49 volts when the car runs I can see 3.8v for 1/2 a second when cranking. can anyone explain the procedure.
Thanks
AJ


Last edited by megatrack; 11-19-2007 at 10:40 PM.
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