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Volkswagen Fox: 1987-1993 88 vw fow won't run

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Last Post: Jun 3, 2009 11:47 PM Last Post By: FKH161
lobok

Posts: 15
Registered: 10/17/08
88 vw fow won't run
Posted: Oct 17, 2008 9:53 PM
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before my car quit on me it would drop rpm for about a minute and then run just fine. I got home and let it sit overnight and drove it the next day and the same thing happened. when I got where I was going I shut it off and now all it will do is a cold start for a couple seconds and die. Checked timing, fuel pressure, and spark.
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Oct 17, 2008 11:27 PM   in response to: lobok in response to: lobok
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How did you check fuel pressure?

If it runs for a second or 2, you know that the timing belt
and timing are OK. What happens when you bridge the fuel
pump relay?
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 2:21 AM   in response to: FKH161 in response to: FKH161
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Well I have pressure up to the fuel distributor and i know the cold start injector works. As far as the timing, I don't know exactly if the distributor runs off the cam or crank, but there is no major noise from the engine when cold started.
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Oct 18, 2008 2:28 AM   in response to: lobok in response to: lobok
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The CIS system is vacuum sensitive... and fuel pressure
sensitive. Pressure at the fuel rail does not mean much
unless you know how much pressure.

You have 2 fuel pumps... it could be that the main pump is
no good, and the only fuel you are seeing at the distributor
is the low pressure fuel pushed by the in-tank pump... which
is enough to spray out through the cold start valve, but is
not enough pressure to push through the injectors.

Make sure all your intake boots are solid and don't have any
broken spots where the boots look like accordion folds.

Remove the boot from the fuel distributor and make sure that
the air flow plate can be lifted (is not stuck down).

The distributor is driven off of the intermediate shaft
wich is driven by the timing belt... again, if it runs for
a second or so, then timing/spark is probably OK, leaving
you with either a fuel pressure or vacuum problem.
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 2:43 AM   in response to: FKH161 in response to: FKH161
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Thanks I will check those but the one one thing I do know is the main pump is noisy so that is how I know that one works. I'm going to check on a intank fuel pump. How do you remove the fuel injectors to check if they're spraying. My manual tells me just to pull on them and they pop right out. I've pulled on them but they won't budge.
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 2:52 AM   in response to: FKH161 in response to: FKH161
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Just one more thing is sparks plugs were carbon fouled.they have been replaced as of today, and the o2 sensor was carbon fouled also
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Oct 18, 2008 2:53 AM   in response to: lobok in response to: lobok
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The best way to pull them is with the correct tool:

http://www.zdmak.com/wbstore/images/SCHH83400.jpeg

The two fingers go under the injector fuel line fitting
like this:

http://www.928motorsports.com/parts/images/injectorpuller/InjectorTool2.jpg

A screwdriver is then put in one of the slots above and then
rested against the valve cover... further pressure on the
screwdriver will lever the injector out (valve cover being the
pivot point).

If your main pump was noisy, check the intank one... simply
remove the access panel in the trunk, disconnect the two
fuel lines and have someone crank the engine (for a second
or 2)... you should have fuel come out of ONE of the metal
fittings next to the fuel sender/pump harness plug.

The blue hose is return, so you could actually leave that one
attached to the sending unit.

If no fuel comes out of the feed pipe, then your intank
pump is no good.
tcovenant2000

Posts: 1,278
Registered: 12/09/03
Re: 88 vw fow won't run
Posted: Oct 18, 2008 10:15 AM   in response to: lobok in response to: lobok
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I pull my injectors with channel locks. Just get a good hold of the hex part (where you could put a wrench) and lever against the valve cover.
As for the carboning, that's usually a sign of a too-rich mixture. You should pull the injectors and see if you're getting any spray.
You test if your fuel pump is working by using a fuel pressure gauge. It's the only good way.
You could have system pressure that's too low or too high, or a bad CPR dumping fuel and causing pressure problems, or even a restricted fuel filter.
Thomas
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 4:39 PM   in response to: tcovenant2000 in response to: tcovenant2000
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pulled the fuel injectors and two broke inside the manifold. Do you have to pull the head or just the intake to remove broken injectors?

Message was edited by: lobok
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 5:29 PM   in response to: lobok in response to: lobok
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pulled fuel injectors which broke but with the fuel pump bypassed and the plate in the intake box pulled up they spray continually
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Oct 18, 2008 6:59 PM   in response to: lobok in response to: lobok
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Put everything back together, bridge the fuel pump relay and
see what happens... I assume you didn't bridge the relay
initially?
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 18, 2008 10:41 PM   in response to: lobok in response to: lobok
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pulled the fuel injectors and two broke inside the manifold. Do you have to pull the head or just the intake to remove broken injectors? but I did bypass the fuel pump but it ran without the key on
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Oct 18, 2008 11:48 PM   in response to: lobok in response to: lobok
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What I meant was... before you took the injectors out, and
before any of us gave you advice, did you bridge the fuel
pump relay and then try to start the engine with the key?
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Oct 19, 2008 10:13 PM   in response to: FKH161 in response to: FKH161
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no I hadn't because I could hear the fuel pump before when I cold startrd it and I didn't know about the fuel pump relay until I had talked to you
lobok

Posts: 15
Registered: 10/17/08
Re: 88 vw fow won't run
Posted: Jun 3, 2009 11:28 PM   in response to: lobok in response to: lobok
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finally got the fox to run. It was the main fuel pump that was the problem. Got one off of a wrecked car. took a little bit but it finally started running again. Thanx for the help everyone!!!!!
FKH161

Posts: 5,903
Registered: 12/29/05
Re: 88 vw fow won't run
Posted: Jun 3, 2009 11:47 PM   in response to: lobok in response to: lobok
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Good stuff & thanks for the update!
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