Engine starts but quickly dies

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wellpapp
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Engine starts but quickly dies

Post by wellpapp »

HI Guys.
I'm having some trouble with my 323i -79 and hoping you could help e with this or point me to some conclusions. I have tried to find and read related issues at the forum but nothing that gives me a straight answer so I'm giv this post a try.
During the autumn of last year I did some work on the car. I changed the the timing belt and tensioner, water pump, the radiator with some hoses and also the exhaust and intake manifold and with it I installed a new cold start valve.
After this I ran it for test run and the it started up as usual. The idle was low 5-700rpm and the engine didn't ran/ignite smooth and was pinking, maybe due to too advanced timing.
I was planing to get do the ignition timed since I changed the timing belt but personal matters came in the way so the car have been standing still till now.

With a fresh battery and things left as it was last year with oil and fuel it starts up after a couple of tries but the dies right away. It continuously do. When I start it up now it revs higher in the beginning which indicates the cold start valve is working compared to before. I installed a new fuel filter, still the same thing. When I started it up for a couple of times it fails to start and only the starter is turning.
I waited for a while and tried again were it starts up and dies right after. Now I trie to run it warm(er) for a couple of minutes and revving 1500-2000rpm.
When I loose the throttle is dies again. It didn't get to normal temperature with the needle straight up, just to the first line.

This is things that I'm thinking of might be the reason:
Warm Up Regulator - due to it have been standing for so long (old fuel) there have been excessive amount of water condensate in the tank which have made the something not work/rust in the WUR. If it have gone bad would it just be causing problem when the engine is cold or oleo when it is warm?
Bad spark plugs?

What do you think?
Thanks in advance!


E21 323i -79
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Jeroen
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Re: Engine starts but quickly dies

Post by Jeroen »

Check it all, that's what it boils down to. WUR could be clogged, ignition and K-Jet way off, dizzy cap, plugs, (how do the plugs look, dirty, black, wet?), fresh battery, fresh fuel, fuel system cleaner. Did you double check ignition timing after the belt change? The middle wheel isn't 180 degrees off?
Regards/groeten, Jeroen
wellpapp
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Joined: Wed Aug 15, 2012 6:11 pm

Re: Engine starts but quickly dies

Post by wellpapp »

Hi, thanks for your reply.
I filled up with new fuel and the plugs were black - changed them, sounded a bit better but the engine dies as before.
With the couple of seconds the engine did run I had the chans to rotate the rotor to get a bit better idle, nothing more timing then that.
So I ended up dismount the WUR, it was deipping clean fuel off the hose coming from the fuel distributor. I took it apart and it was filled with a black fluid. Should it not be filled with clean fuel if any?
The resistor winded around the bimetal strip was "burned" and only measuring 1-2ohm wheras it should measure 24 +/-4 ohm.
Could this maybe be the problem or was this caused by something else, other then it have been staying for almost a year?
Under the WUR it was all clean and the screw going in to engine for heat transition was also clean and unoxidated.
E21 323i -79
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Jeroen
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Re: Engine starts but quickly dies

Post by Jeroen »

Well the WUR shouldn't be filled with anything, most likely it got filled up wit oily fumes through the breather hose, which may have caused a short circuit and a dead bimetal. It could be stuck in any position, hard to tell but clearly it needs replacing. Thing is that the black plugs don't mean much, just many starting attempts mean a lot of fuel hence black plugs. But if you have a decent spark and ok ignition, it may very well be that you're not getting enough fuel at startup. Injectors not opening, or not enough fuel coming from the distributor. Enough for a brief bark and that's it. Did you check if the lever of the fuel dizzy is moving ok? You can do another start attempt while pushing the lever from below, that gives some more fuel. Make sure all ignition parts are decent and checked and that you have a spark indeed.
Regards/groeten, Jeroen
wellpapp
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Joined: Wed Aug 15, 2012 6:11 pm

Re: Engine starts but quickly dies

Post by wellpapp »

Thank you for the information and tips.
Do you mean the lever for the baffle plate and air flow sensor connected to the fuel distributor?
Could it help trying a fuel system cleaner?
E21 323i -79
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Jeroen
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Re: Engine starts but quickly dies

Post by Jeroen »

yes, and yes

:P
Regards/groeten, Jeroen
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