cold starting issues 78 530

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want2know
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Joined: Mon Aug 02, 2010 12:21 pm

cold starting issues 78 530

Post by want2know »

I need to get my 78 530 runnning better. It was a dailydriver until 5 years ago. Since then Ihave run it occassionally but not often. It will start when cold if I work at it. Initially it fires and idles for a short 5 to 10 seconds. then it just shuts down. It will rarely rev if throttle is opened. But when I can get it to rev over 2000 then it will generally operate smoothly. Starting when hot is usually not a problem.
here is what has been done so far. Drained gas tank, replaced fuel filter. Replaced all fuel injector connectors, as well as cold start and thermotime switch connectors. Checked aux air valve when cold (it is open). Replaced mass air flow housing with a used one . Spark is good. Timing is set to 9 before when idling at 1000 rpm with all vacuum hoses connected.
I have checked for air leaks and vacuum leaks with engine running and spraying carb cleaner on hoses.
I've also tried to google these symptoms and have done a lot of reading in your archives, but no luck
I was thinking of using contact cleaner and dielectric grease on all wiring connections, but haven't done so as yet
Any one have some suggestions?
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Falkenberg
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Location: In Europe, far, far away.

Post by Falkenberg »

I don't think you've used the correct method to set the timing.
Do you have a cold start injector? Is it working?
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want2know
Posts: 4
Joined: Mon Aug 02, 2010 12:21 pm

Post by want2know »

I understand the timing may not be exact, but it is an alternative way to get the timing close. The cold start injector works. I have been wodering if the ground circuit may be at fault. Not firing the main injectors, but the cold start is working. could the car start with only the amount of fuel supplied by the cold start injector? I won't be able to check this out until the weekend.
just a thought
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Mike W.
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Post by Mike W. »

I'd start on checking fuel pressure. Hook up a gauge and see if you get a lot of bleed off. And or pull the air filter boot off, press on the AFM flap to run the fuel pump for a while and see how it does.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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