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-   -   What is this !! Never seen this problem before. (http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/509722-what-never-seen-problem-before.html)

JFairman 11-29-2009 05:19 PM

The fuel line attaches to the injector with a compression fitting. If that type of fitting is overtightened the collar can be creasesd or distorted and will leak.

RarlyL8 11-29-2009 06:12 PM

Yes I suspect these lines have been over tightened in the past and now are leak prone.

There were 2 problems with cylinder #3, the fuel line was leaking at the injector causing the fuel drip under the engine, and the fuel injector was bad having a crappy spray pattern and leaking.

What do you think caused the sudden rough engine after the boost run? I think that is when injector #3 went south and possibly a bit of debris broke loose when I cleaned it and stuck in the pentle when it opened wide during the boost run. What puzzles me is that all the fuel lines are now leak free, injector #3 has been changed and the car still does not run right.
I've looked for vac leaks and still think I may have created one somewhere that is not obvious.

JFairman 11-29-2009 06:34 PM

There's a fine little conical fuel filter screen in each injector and any debris from orings breaking down or corrosion from the euro cast iron fuel head should stop there.

Carbon from gasoline eventually builds up on the injector pintle and seat and it can have a lousy spray pattern and or leak down into the intake ports after shutting the motor off because CIS injectors stay open all the time unlike electronic injectors that are constantly opening and closing so they stay clean.
Using the best gas and techron or seafoam helps to keep that stuff somewhat rinsed off.

Hard to say whats going on with yours without seeing them and sticking them in empty clean 12oz water bottles and pressing the sensor plate down while the pumps are running and watching the spray pattern and measuring the fuel quantity from each injector.

If you have 6 good lines and injectors coming in the mail you could try those.

RarlyL8 11-29-2009 08:39 PM

I have not disected injector #3 but suspect that I may have damaged the screen when i clean the injectors. A pump was used that can generate more than 100psi.

The pattern was checked using glass bottles and is how I found #3 to be faulty.

Yes I am waiting on this used system to arrive so I can swap parts. I know what I need to do but dread doing it as I am so strapped for time. I posted this follow-up in hopes that someone would spot something I haven't thought of of may have had something similar happen to them.

Thanks for the input and I'll follow up again when I get the parts changed.

h20cooled7 11-30-2009 12:13 PM

Not to be an ass ,but what about new injectors at this point? I tried cleaning my injectors but still couldnt get a good spray pattern. If you dont get atomized fuel or a dripping injector your gonna get a misfire on that cyl or cyls. I combed the web and Robert at Lufteknic had the best price $90 something.

RarlyL8 11-30-2009 06:02 PM

Yes new injectors will be ordered if these used ones don't pass.

One additional kick-me-while-I'm-down I didn't mention happened a couple weeks ago when I bought a set of injectors from a board member. I received air injectors. :rolleyes:
Yes this has been one for the books.

jpnovak 11-30-2009 07:03 PM

Brian, I have a set of N/A CIS injectors that are 6 mo. old. they were removed for an EFI install. Make me any offer that won't be refused. (Shipping should cover it). PM an address and I will put them in the mail.

RarlyL8 11-30-2009 08:40 PM

Thank you so much! This has turned into one of those deals where I'd been better off buying new from the start. Trouble is you don't know that going in ...

mb911 12-01-2009 04:13 AM

I vote spark plug wires are in the wrong order. I can't tell you how many times I have seen the exact issue to only find out good intentions went bad

RarlyL8 12-01-2009 05:10 AM

Ha! Yes Ben I checked that several times. I actually removed the new wires/cap/rotor and put the old ones back and then re-replaced them one component at a time. Checked the firing order written on the wires as well.

Here is an important fact -
When cold the car starts up perfectly and runs for a few seconds perfectly then begins to get rough as it warms. Within 10 seconds of starting it runs crappy. This is why I believe the problem is AFR related (fuel or vac leak).

WERK I 12-01-2009 07:45 AM

The leaking injector has also contaminated your oil. I don't see it mentioned anywhere in your updates, but you should change it immediately.
Regarding your leaking injector(s), your cleaning probably loosened some particles trapped inside and have rested on the pintel valve seat or worse, a bent pintel. :(

fredmeister 12-01-2009 07:50 AM

if its a vacuum leak try running some small amount of propane around all the possible sources of leaks to find where. you can use a propane bottle and brazing nozzle unlit of course to direct the propane at the connection. carb cleaner may not work as well because of environmental issues making them less flammable which used to be a cheap way of checking as well.
you just need to do a process of elimination to track down the culprit. Is it possible your CD box is on the way out? Mine faled suddenly one day as well with no warning, except a slight misfire once or twice before total failure.

RarlyL8 12-01-2009 12:47 PM

Dave, the engine has been out 3 times so the oil has also been changed 3 times. Oil alone has cost me a small fortune!

Fred (?), I have thought about the CD box as I have unpluged it several times now. A SunTune machine would sure come in handy about now.
The engine runs consistantly bad and has resonded every time I fiddled with the injectors. Right now I believe that more than one injector has failed. The next step is to pull all the injectors one more time and swap with another set that I will bench test before installation. That will either fix the problem or eleminate injectors as the source.

rsrfan 12-01-2009 01:44 PM

Here is an important fact -
When cold the car starts up perfectly and runs for a few seconds perfectly then begins to get rough as it warms. Within 10 seconds of starting it runs crappy. This is why I believe the problem is AFR related (fuel or vac leak).[/QUOTE]


Brian. Check your thermotime switch. It is my understanding that if it goes bad it will continue to provide a ground path after initial start which would result in flooding of the engine via the cold start valve. Should be easy to test by disconnecting the ground lead. Its a stretch, but...

RarlyL8 12-01-2009 02:51 PM

I'll check that but I do not think the engine is running rich (no fuel smell or smoke). It sounds like it is missing on a couple cylinders. My AFR meter is not working as the lead is too short for the new bung. Must fix that as well ...

nocarrier 12-01-2009 04:49 PM

I had a similar problem with my 930.

It ran great when cold but after it warmed up it would start missing and would buck under load.

I even started a thread about my bouncing air meter plate.

It ended up being my CDI ( it was a permatune) I guess when it was cold it was working ok but as soon as it got hot it started to die....

I ended up confirming it was bad by finding an open across the negative and chassis ground.

Perhaps your cdi could be acting up as well.

911nut 12-01-2009 05:36 PM

Quote:

Originally Posted by jpnovak (Post 5040576)
Brian, I have a set of N/A CIS injectors that are 6 mo. old. they were removed for an EFI install.

N/A injectors, which are held into the blocks by an o-rings, won't work on a 930 engine as the 930 injectors have threads and screw into the blocks.
I don't think that there is an effective way to really clean CIS injectors. I had 3 bad ones and I replaced them with new. Not cheap, but cheaper than a burnt piston.

RarlyL8 12-01-2009 08:52 PM

You're probably right Paul. My goal was to wash away any deposits that might have formed over the years. It looks like I should have left well enough alone. I had suspected that at least one injector was leaking due to a few subtle symptoms. When I did the check #6 was in bad shape and leaking so I replaced it.
I recieved a complete Euro CIS system today from a fellow Pelican in CA. Now if I can only find the time to swap some parts.
JP told me that the injectors he has have 930 part numbers. If they are in fact SC injectors you are correct, they won't work.
This problem I am having is consistant and reproducible. The car will fire right up and run god for maybe 10 seconds max before degrading to a rough idle that gets worse with time. CDI? God I hope not after chasing these injectors for 2 months.

JFairman 12-01-2009 09:11 PM

If you have the 930 ignition delay relay in your car then an injector that leaks down quickly will often make the engine sort of stumble on roughly on the cylinder(s) that have leaking injectors.

Without that relay that keeps the ignition on for almost 5 seconds after the key is turned off that won't happen.

RarlyL8 12-02-2009 05:02 AM

I don't have that relay (and find it anoying in the cars that do).
Hope to steal a few moments this weekend and tear it down again. Will report back when She is back together and can be fired.


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