930 (1987) Stall-Out

[westbrook4]

My 930 has developed a bad habit where it stalls out after about 10 minutes of problem free operation. This has happened the last 6 times that it's been driven. Initially the car would be able to be restarted after about 15-20 minutes, but the last time it wouldn't get going for 2 hours. I have been playing with the ignition system, but can't trace the problem. I have also thought about the ignition switch. I doesn't seem to be fuel related. Any suggestions?

[wvicary]

Have you replaced the DME relay under the drivers seat yet? That's where I would start, they are known to fail with age and are the main relay for the fuel injection system.

[cibergypsy]

Have you replaced the DME relay under the drivers seat yet? That's where I would start, they are known to fail with age and are the main relay for the fuel injection system.

I think the 930 doesn't have a Motronic system on it. Its fuel injection is like the one on the Ferrari 328s. I think this system doesn't have a DME since the fuel metering is not done by a computer but by a fuel distributor together with the air flow metering unit - which has a plate that hinges almost frictionless and has a cone shape funnel in which it moves and the air entering into the system is controlled by this mechanical system. That cone shape is made for each model car specifically and there is no computer to meter the amount of air or fuel coming into the intake, this is something which is mechanically done and already set with no easy way of tweaking it.

You need to look elsewhere and, since I am not a specialist or a knowledgeable mechanic, you should take it to a specialist to find out. This system is all about fuel pressure and has some check valves and other mechanical-hidraulic systems that need to be checked. It is a very reliable system and I found it more to my liking in my Ferrari 328 than the Motronic I have on my Carrera. It's just not as fuel efficient and not as "green".

[magcuda]

you need to get a fuel pressure gauge and a pressure /vacum gauge and get some technical info on your car. I lost all my old turbo stuff. with out some readings you can guess all day at this thing

[westbrook4]

I replaced the DME relay, to no avail.

Any other thoughts?

[SkipC]

Narrow it down. After it stalls but before it will re-start, will it crank but not start or not crank at all ? If it will crank over, then crank it and check for spark. This will, hopefully, tell you whether its an ignition or fuel problem.

Good Luck, Skip

[Chuck Jones]

When I first got mine it was all original and it stranded me a couple times...just quit after it would sputter a bit, then die and wouldn't start. turned out to be a faulty CDI box that was going out. Replaced it with the MDS 6Al which also has rev-limiter inserts that you can put in. I put in one that dropped the rev limit to 6500....The MSD runs a hotter spark also.

[Rixter]

the 930 is CIS mechanical fuel injection (K-jet) and does not have a DME. Fuel/air mixture is controlled by the warm up regulator (when cold) and then by the mass air flow. I suspect you have an issue with the CD box or the fuel pump. Either could be on it's last legs and acting up once warm.

[PCar SBO]

I think your CDI box is going bad. This is a comon failure mode. They quit when getting up to temperature and re-start when you cycle the ignition after letting it cool down. Once this happens confirm whether you have no spark. If that is the case you can contact me at 3.6[at]cox.net - I rebuilt CDI boxes for a fee if you are interested.

Cheers,

Ingo

[magcuda]

a good place to check is also the pick up coil in the dist. I would check that before throwing a $$$$ CD box at it