924Board.org

[samivaan]

I have a problems to start my car, when it's warm/hot, and been shutdown more than one/few minutes.

Already fixed or checked
-WUR changed from other car. Helped for cold run problem. Didn't effect for this
-Air auxiliry changed from other car, don't have any effect for this, just for cold idle rpm
-All vacuum lines fixed (found many broken connections), helped an idle run, but not for hot start problem
-Thermo time switch checked, works fine
-Cold start valve don't leak, works fine

And finally, there still is one 100% sure way to start my car with hot/warm engine! I just switch electrics on from the key, but don't start in first 2-3 minutes. Then I start, and car really start up normally! If car has been shut down just around 5 minutes, I might need to keep electrics on about 2-3 minutes before start. If car has been shut down 30 minutes, 0.5-1min might be enough, but still needed to do.

So, last place where is any bi metal parts, which warm up with electric, is in air flow meter?! Why there is electric income, and that bi metal thing? I have seen some 10 years more new k-jets, and they don't have it? Can it make problems like this?

PS. I feel that my car runs a little bit too rich mixture, where should I lean it? I know that it's possible to get more rich mixture with adding shim plates for system pressure screw, but how to remove shims, if system is stock, and the there is no shims?

[Diesel]

Try one more thing; make sure that EVERY fuel line doesn't touch the engine. Put bits of old heater hose in between if you have to. Make it so there is no way the engines heat will soak into the fuel. Get back to us when you've done this and let us know.
_________________
Dan Flanagan--2002 VW Jetta TDI, 83 Mercedes 300D,83 Mercedes Euro-240D

[924guy]

check your positive battery cable.... i went through a similiar issue with my 78, and the positive cable was deteriorated and apparently somehow increasing resistance in the electrical system when it heated up from the engine, and affecting its ability to fire the engine.. there was no noticable change in starter output, ect.. a very strange issue, but sure enough, after replacing it (new one has to be custom built as there no longer available) the problem dissapeared... it was really freaky and ive yet to understand how it was possible..( i didnt quite grasp the mechanics explaination) but apparently that was the issue with mine at the time...weird...
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[-nick]

If the above quick fixes don't work, then your next step is probably to use one of these:

http://www.fastforward.ca/Tools/default.htm

and check to see if you're loosing too much fuel pressure after shutdown. It's a typical problem. The culprit is usually either old leaky fuel lines, the fuel accumulator(s), fuel pump check valve, or the check valve in the fuel distributor head.

I would suggest having a shop adjust the mixture. It's best to use a exhaust gas analyzer (or similar) for this.

-nick

[numbbers]

Check the tech section. Much info on hot start problem.
_________________
1980 924 Turbo

[Roger]

Leaky injectors can cause a hot start problem. Pull you injectors and test them.
_________________
1981 924 NA

Some people are like Slinkies. Not really good for anything, but you
still can't help but smile when you see one tumble down the stairs.

[samivaan]

Diesel, thanks from the advice. Several fuel lines, touched the engine/head. Put them way better, but didn't get it to work still. Had to still check it more carefully. Weather in here is pretty cold, and problem can be even a half hour from the drive, so maybe fuel boiling is not a problem?

Numbbers, checked, and seems that I've been done those same checks already.

Roger. cold start vavle didn't leak, but that is true, maybe other injectors leak. Had to check. I just checked spark plugs again, and two of them were too black, and two of them were too white. So seems that they won't work correctly. Which is weird, I checked them 2 months ago, and those fuel output was equal with each other.

[Racing]

Check this;
http://www.924board.org/viewtopic.php?t=11456

[Rafael]

Put a botton to activated the cold start valve(inyector), like is on the tech seccion (I think) but read what i wrote some time ago, i make some modifications to it.

First of all, the botton like you have, only works when the engine is cracking after you left the key of the contac in normal position, the power to the cold start valve it´s of, and the engine need more fuel to run.
Try this, take the contats of the cold start valve apart disconect the wires and cut it (THIS IS VERY IMPORTAT because the wires that come from the car are given + or - to the valve) take + from the battery directed and the ground with the botton, so you have all the control to activated the cold start valve, and left it the time that you want and the time that the engine need to run well.
When the engine cold you must push the botton to start because know you have the control of the valve, and in warm starts you push the botton and when the engine start left it some time until you feel the engine is run ok.
If it works to you you can put it a fuse, and some reles like i did for the cold starts.
Try this and tell us.
Good luck.

[-nick]

2 black and 2 clean plugs is pretty tell-tale. Either you've got 2 leaky/bad pattern injectors or the fuel distributor is having problems. Pull the injectors out and see how they spray and if they all shutoff at the same time. If they're different, then switch them around and hope that the problem follows the injectors! Injectors are cheap & easy compared to good fuel dizzy's.

-nick