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Fuel pressure/WUR problem???

Hi.
I have a 83' 3.3 Turbo engine in my car.
Here the other day it started to behave all weird on me.
When giving throttle, it would not fire (approx @ 3800rpm) and I had to ease up on the throttle to get her going again.
When she did fire (a little on and off) the boost didn't go Any higher then 0,5 Bar.
So i drove into a gas station to take a look. When I got back there, it was clearly that she gets way to much fuel. It was hard to breathe and my eyes hurt.
So I took a look at the spark plugs. They where realy black.

So I'm thinking it's probably some trouble with fuel pressure or WUR.
Anyone ?
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Old 07-31-2007, 03:48 PM
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wcc wcc is offline
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I can't tell you what's wrong with your car, but I can tell you that your plugs are supposed to be black and sooty. Of course if your car is stock with the stock spark plugs (W3DPO).

It does sound like you have a major fuel leak.
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Old 07-31-2007, 04:58 PM
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The spark plugs had more like an layer of soot.... So im thinking the soot is preventing ignition and thats why i get a lower turbo boost. ( No ignition = no exhaust = no boost)
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1978 911 SC
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www.pelicanparts.com/gallery/dozer
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Sorry about my English... I'm Norwegian

Last edited by dozer; 07-31-2007 at 06:01 PM..
Old 07-31-2007, 05:07 PM
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Well you may want to post a pic of them cause they really are supposed to be that way. They (Porsche) put in a cold plug so that is why that's normal. When I saw mine for the first time I thought there was something wrong with the engine, but it was normal.

Here is a thread that may help shed some light on the plugs.
What's up with Spark Plugs?
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Old 07-31-2007, 05:18 PM
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Well, it's to late posting pics now.... I've already cleaned them.
Decided to instal new plugs after I took a look at them...
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www.pelicanparts.com/gallery/dozer
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Sorry about my English... I'm Norwegian
Old 07-31-2007, 11:29 PM
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Ok,so the plugs supose to black.But I don't think they supose to have a layer os soot on them. I still belive the lack of ignition and boost is caused by the AF ratio beeing WAY to out there..
I would be grateful if annyone could confirm my theory about this beeing caused by a fuel pressure or WUR problem.
What is your bet? Fuel pressure regulator maybe or WUR?
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1978 911 SC
G-50 / 3.3 turbo / coilovers / RS 3.8 look
www.pelicanparts.com/gallery/dozer
http://www.pelicanparts.com/gallery/dozer/
Sorry about my English... I'm Norwegian
Old 08-02-2007, 05:07 PM
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I know you probably don't want my advice, but you can get these tools to check the fuel pressure and AFR. Then you'll know the FP & AFR instead of guessing.

http://www.jcwhitney.com/autoparts/Product/Pr-p_Product.CATENTRY_ID:2008126/c-10101/Nty-1/p-2008126/Ntx-mode+matchallpartial/N-10101/tf-Browse/s-10101/Ntk-AllTextSearchGroup?Ntt=fuel+pressure+tester

Also, the LM-1 is the most popular AFR data logger that you can use to check your AFR. I use the Gunson Gas Tester for my car. One day I'll pick up a LM-1.

http://www.eastwoodco.com/jump.jsp?itemID=5247&itemType=PRODUCT

http://www.innovatemotorsports.com/products/lm1.php

Lastly, you can remove your WUR and test it by cooling it and heating it. You'll have to search for the exact process of testing it. Then you'll know if it's operating normally or not.

Sorry I'm not more helpful in saying it's for sure your AFR or your fuel, but these tools are just about a must have anyways IMO. This would be my process if I was experiencing your problems. Good Luck!
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Old 08-02-2007, 05:38 PM
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Bill, I apritiate all advice I can get on this matter, including yours
I just think the sotet spark plugs is a result of to ritch mixture.
Remember the fumes from the exhaust... it made my eyes burn and it was hard to breath.
It clearly is a matter of fuel mixture,and I see the sooted plug as a result of this and not a reason for my problems.
Hence the topic: Fuel pressure or WUR problem?
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1978 911 SC
G-50 / 3.3 turbo / coilovers / RS 3.8 look
www.pelicanparts.com/gallery/dozer
http://www.pelicanparts.com/gallery/dozer/
Sorry about my English... I'm Norwegian
Old 08-03-2007, 11:49 AM
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As you have stated, a sudden rich condition can only be too much fuel, not enough air, or a weak spark.

A CIS engine depends on the air flapper valve to mechanically meter the fuel.
The fuel head and WUR regulate the fuel pressure.
The dizzy regulates the spark.

I would first check the system fuel pressure and the warm pressure. The WUR may have a blown diaphragm causing the pressure to dump.
If that's not it check the spark of each cylinder.
Let us know what you find.
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Old 08-03-2007, 12:21 PM
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Believe it or not, you could be experiencing a lack of fuel pressure delivery. Has anyone ever run their turbo out of gas? The last thing it does before dying is belch out black smoke from a way-rich mixture. The reason is the first thing to go is the control pressure which allows the metering plate to relatively over-open vs. the air delivery. Also the fact that your car does not want to run over 3800 RPM is an indicator that it may be running out of fuel. You will need to conduct a fuel pressure and delivery test to confirm if this is the issue.
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Old 08-23-2007, 05:26 PM
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Quote:
Originally Posted by 930turbo View Post
Believe it or not, you could be experiencing a lack of fuel pressure delivery. Has anyone ever run their turbo out of gas? The last thing it does before dying is belch out black smoke from a way-rich mixture. The reason is the first thing to go is the control pressure which allows the metering plate to relatively over-open vs. the air delivery. Also the fact that your car does not want to run over 3800 RPM is an indicator that it may be running out of fuel. You will need to conduct a fuel pressure and delivery test to confirm if this is the issue.
So are there lingering effects of running it out of fuel. Do pressures have to be adjusted, etc.?

Thanks.

RT
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Old 08-26-2007, 09:59 AM
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