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orange julius · Posted: Sat Jun 26, 2010 6:47 am Post subject: Stopped No Apparent Reason

Hoping someone could help. Car woudl not start- found it was the coil, replaced coil with new one, repalced plugs, cap, rotor battery wire.
Started car one day, drove about 1 mile then all of a sudden lost all power and teh engine just stopped- could not start it again.
Checked all wiring everything seems fine, engine turns over.
Luckily my boys were home and could tow me back home.
Anyone run across a problem like this- please point me in the right direction.
Your help would be appreciated!!

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Orange Julius

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Not buying your initial diagnosis. Coil failures are pretty uncommon. . .sounds like you have another intermittant problem.

Could be a bad ignition switch, bad DME relay, bad crank sensors or sensor cabling. You need more diagnostics. Does the car have fuel pressure? It is getting spark?
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

bcblase · Joined: 23 Oct 2007 Posts: 574 Location: Winchester, VA

+1 for Rasta.... probably was not the coil.

Fuel pump DME relay or the pump itself would be my guess.

We need more info.
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1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver

orange julius · Posted: Mon Jun 28, 2010 10:18 pm Post subject: Check

Will check to see if fuel is pump is working- I have no diagmostic tools to check- will also check for spark - thanks.
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Orange Julius

orange julius · Posted: Tue Jun 29, 2010 10:46 pm Post subject: Relay

Replaced relay ( not easy to get to). One thing I did notice was that in the past when I started the ignition I used to hear some thing activating- I am guessing that was teh fuel pump. I don'thear that anymore. Would this be because teh fuel pump is gone?

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Orange Julius

orange julius · Posted: Thu Jul 01, 2010 12:33 am Post subject: Closer to solving the problem

This is what I found:
The spark plugs are getting a spark
I replaced the fuel pump relay- verified that in fact it was not working
Brand new one installed
Checked for fuel flow- no fuel.
I found in the wiring diagram that their is another in line fuse
Any one have any idea where that can be found?
Thanks.
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Orange Julius

bcblase · Joined: 23 Oct 2007 Posts: 574 Location: Winchester, VA

Fuel pumps are known to fail in these cars - especially the original 22+ year old pumps.

You might try removing the pump and trying to power it manually. Actually, it might be easier and safer to just disconnect the power leads from it, and try powering it in place with a spare battery before you remove it.

Those old fuel hoses can get brittle with age, and you don't want to replace a $200 pump if you don't need it, plus risking damage to the fuel hoses.

Brad
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1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

masterdave · Joined: 10 Dec 2008 Posts: 183 Location: Harrison NY

sounds like its a fuel delivery issue, i had a similar problem turned out to be the grounding cable on the fuel pump. the best solution that i found was to bypass the ground wire and make an independent one. Under the rear mat you will see a grounding point for the back light array, i sanded mine down with some medium grit sand paper and ran a 20 gauge wire from it to the fuel pump ground connector. I put the wire through the chassis at the bottom of the passenger side "secret compartment" where the sun roof drain comes out. This took care of the problem once and for all no more intermittent starts for any thing like that. In my opinion the wire they used in the first place was too thin.

orange julius · Posted: Mon Jul 05, 2010 11:49 pm Post subject: Wiring

Interesting- seems like I have 2 pumps- one in the tank and one outside.
Am I seeing this correctly- as I see wiring coming out of the tank ( Hex head ) and wiring going to another unit right above it- could either be the problem and which one do you replace- I will try a direct connection to the one of them an see what happens.
P.S - I had already cleaned that ground as I had issues with the rear lights.
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Orange Julius

orange julius · Posted: Thu Jul 08, 2010 10:55 pm Post subject: Fixed!!!

Guess what guys- found the problem and take note!
The fuel pump is okay- the problem was a short in the cable harness just under the trunk. When you follow the fuel pump wiring harness underneath the car ( yes it is actually very tricky to see- their is a welded bracket that holds ths wire to the body- this had actually cut through the wire and this is what caused the short-causing both the fuse and the relay to go.
I am happy motoring again after almost 2 months.
Can't wait to find out what will go next......

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Orange Julius

bcblase · Joined: 23 Oct 2007 Posts: 574 Location: Winchester, VA

Good find!

Troubleshooting is an exact science if done by the book.

Brad
_________________
1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver

TJC · Posted: Sat Jul 10, 2010 1:11 am Post subject:

Super! Thanks for the update, something to tuck away for future reference.
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