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[Michael Kouridakis]

Has anyone experienced the ridgid fuel line to the fuel injectors twisting when trying to remove the nuts on the injectors? I'm using the correct wrenches-- one to hold the body nut of the inj and another to loosen it. My car still runs like **** below 1500 rpm and is usually hard to start after it's been sitting. The fuel pump runs when the engine is running. Could my injectors be leaking down pressure? They're supposed to hold pressure when the car's off, right?HELP

[larso]

THe injectors have two places you can hold them, the rubber 17 or 19 hex whatever size (the big one that actaully threads into the cylinder head, they are like inserts for the injectors), and also the small one, 13 or 12, the metal part of the actuall injector...
IF you can't get the lines off with holding one, try the other, and/or hold both while turning the injector line hex spindle nut thing.
Wear a glove, your knuckles get bashed , these things atomize over the years together, because of heat, a tad of corrosion, metal to metal.

[larso]

Oh yeah, and since your car is running rough , what RPM is it idling at when you first start it up?

Does pressing the throttle smooth it out or does it just studder? If it studders it is too lean, meaning the WUR is shot, the injectors are clogged/worn, or some other possiblities such as mixture...

[numbers]

I replaced the injectors on my '80 931 last year, and only had one line start to twist on me. Use your two wrenches, and as soon as the connection breaks loose, tap on the fuel line where it goes into the connection and it will free-up. Then spray a little WD-40 on the connection to give the line a little lubrication. It should spin free from the line. If your experience is like mine, you will be amazed at how smooth you car will idle and run with the new injectors.

[D Hook]

I just had all four changed and both the rubber intake boots had small cracks. After that, the idle is smooth. Still gotta' do the WUR before the weather turns. It starts rough but smooths out within 8-15 seconds. Check the boots, too. Replace w/new if you can, not used.

[Michael Kouridakis]

Thanks for all of the advice guys. I did finally get the injectors out and cleaned them and the head. The car is running much better now but it takes a while to warm up. What happens is that it runs and dies for the first few start-up attempts even if I press the pedal to keep it running. It does the juddering thing you mentioned Larso. When its warmed-up it runs well but I can still feel a very subtle judder and it won't idle. Should I adjust the idle set screw up higher? How do I adjust it if it's running lean? And lastly--- what's the WUR????
Thanks

[larso]

Do all adjustments when the car is hot.

That's what your base should be. If it idles at 900-950 once warmed up, then the Warm up regulator must be bad in YOUR situation...because if you are pressing the pedal down and it isn't doing anything but stalling, the mixture is too lean, and it is not the fault of the AUX air regulator.

The idle screw u should adjust when car is hot too, since that is your base (that's when u drive the most).

If your car is a little hesitant and juddery once it's hot, and it has slow throttle response, then the mixture could be off, but if it's bad only when cold, it's the warm up regulator.

It sounds like your mixture is a little bit off, since it is a little bit juddery (is it when you drive it?), AND you have a WUR problemo.

Once you adjust the mixture the little bit needed it will most likely move your idle up, but if it moves it down then you may need to adjust idle screw.

[ This Message was edited by: larso on 2001-08-19 04:09 ]

[Michael Kouridakis]

Thanks Larso, I'll give it a try. Where is the WUR. I'll just replace it when I get a chance. It does a very subtle juddering at speed even when warm sometimes. When I try to keep it idling when hot by goosing the pedal up and down it sometimes misses and sometimes it will backfire, but the backfiring is very rare.

On the plus side-- it's so fast. I can't believe it. This is easily the coolest car that I have ever owned and I've had a bunch. On my way to work there's an exit ramp off of the highway that turns into a lovely group of S's. The first time I took them I went in way too slow for the 931. I just pressed the rt foot down and she hooked up and accellerated fast. The feeling is awesome!