Car shutting off

[Ripp87Turbo]

Installed MSD Blaster 2 Coil, starts up fine, but now will randomly shut off, I also have a Lindsey racing boost enhancer, but when the car shut off I was barely in boost, which removed my suspicions of overboost. After a couple of times it seemed that when when the car was in gear and going downhill or coasting, no throttle, it would shut off. Along with the random shut-offs was significanlty loud backfiring, note I have no cat either.

Not sure if if I screwed anything up, when I got the coil, I had disconnected the old one, when I put the new one on I instinctivly without thinking put the black wire on the neg side and the green wire on the positive side. Well after 3 miles and a no-start after parking and a checking of all my fuses I noticed it was reversed. I corrected it and disconnected the neg terminal on my battery for a few minutes she fired right up and drove perfectly. The first paragraphs instances took place the day after. I'm really stumped, I thought it might have been the coil but it ran perfect that same day. Also the MSD coil is a little smaller than factory so I used some silicone vacuum hose as a spacer and tightend it down, it's not a sturdy as the stock one but it doesnt rattle.  And if this info helps I've got an Optima red top gel batt, bosch cap and rotor, msd wires and bosch super 2's, fuel pressure gauge, boost enhancer, no cat. My factory computer is probably so confused.

Any help would be greatly appreciated. I really want to attend the rally this Sunday.

[Darren]

Is it a 944 Turbo?  Assuming so, it's fairly common for the DME relay to go wonky.  Most 944T guys travel with a spare.

[michael lang]

Based on the description of the problem, I'm thinking that the fuel mixture may be too lean and would be thinking there is an issue with the MAFS. Try cleaning the contacts on the wiring harness and the MAFS with some electrical contact cleaner first. Please let us know what you come up with.

 

[Darren]

It's a 944 thing, search on Rennlist about it.  I would pull over, tap my DME relay and eventually it would start.

[Ripp87Turbo]

2 quarts low on oil. Goin around turns or hills it would stall, assuming it has a safety cutoff to prevent engine damage. Not leaking any oil, must be burning it, but Ive had the car for 2/mo and always told myself, ill change it ill change it. Ive done everything else to it except that. Anyway thanks for the tips guys.

[michael lang]

I don't know, that'll be the first time I've ever heard of an oil change fixing a stalling/loss of power symptom. Has any shop performed any diagnosis or made any attempts at fixing the problem? If not, then why not take the car to a shop and have them atleast figure out what is going on?

 

[Ripp87Turbo]

The car has not stalled since the oil change and now the oil pressure is 4 at idle and 5 at acceleration. Also the fuel pressure gauge I installed now reads rapidly between 30-34. I'm going to do the fuel pump next. And the filter I used is a genuine porsche oil filter and I used mobile one 10w 40.

[Darren]

I didn't know they added an engine cut-off in '87, I'll have to look that up.  I don't think it's there on the '86.  The '87 and later has a level sensor in the pan, but that causes a light to go on not the engine to shut off.

Remember, it's impossible to prove a false negative.  Just because it hasn't left you stuck doesn't mean the problem is fixed.  I'd order a DME relay and keep it in the glovebox.  It's a good idea for any 944 turbo regardless of your issue.

[michael lang]

Ripp87Turbo wrote:

The car has not stalled since the oil change

I'm happy for you that the problem was something that simple. Boy am I glad that not all car problems are that simple, I'd have to start selling "mechanic in a can" to make a living!