My car stalls when I hit the brakes or turn hard....
07-09-2007, 08:51 AM
#1
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My car stalls when I hit the brakes or turn hard....
I've been troubleshooting this intermittent stalling for a week now, and it's been driving me crazy.
1. The car must be fully warmed up before it will stall.
2. Once warm, stopping or turning will upset the idle or make the car stall ...otherwise it runs fine.
3. After the engine bay is fully heatsoaked, the car will not even idle or drive until it cools a bit.
I am trying to determine if this is a Permatune thermal related failure or some kind of fuel delivery problem. To make the car stall by stopping hard, but ONLY when hot is bizzare at best.
I have a MSD 6A ingnition module I can install in place of the Permatune.
Any help is appreciated! Does anyone here have experience with something like this..... and am I on the right track ?
1. The car must be fully warmed up before it will stall.
2. Once warm, stopping or turning will upset the idle or make the car stall ...otherwise it runs fine.
3. After the engine bay is fully heatsoaked, the car will not even idle or drive until it cools a bit.
I am trying to determine if this is a Permatune thermal related failure or some kind of fuel delivery problem. To make the car stall by stopping hard, but ONLY when hot is bizzare at best.
I have a MSD 6A ingnition module I can install in place of the Permatune.
Any help is appreciated! Does anyone here have experience with something like this..... and am I on the right track ?
07-09-2007, 12:49 PM
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Just a general note on ignitions, make sure your wires are well shielded and kept seperated from each other. People have had mystery gremlins from wiring when they go to aftermarket ignitions. I am not suggesting that that is the problem, just want to point out that you have to pay attention to your wiring whenever you mess around with the ignition system. They sell clips that are made to keep your wires from touching each other.
Probably not related to your problem, just something to keep in mind. people also use magnacor wires because they will not pick up electromagnetic interference. Richard at Clewett engineering sells his own version of those expensive magnacors.
not that this is likely to be the problem...I would think that a real ignition issue would show up under any circumstances, not just specific times.
Probably not related to your problem, just something to keep in mind. people also use magnacor wires because they will not pick up electromagnetic interference. Richard at Clewett engineering sells his own version of those expensive magnacors.
not that this is likely to be the problem...I would think that a real ignition issue would show up under any circumstances, not just specific times.
07-09-2007, 12:56 PM
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It almost sounds like it could be your warm up regulator not adjusting to temperature correctly, but I would need to defer to an expert on this. The WUR is really delivering fuel all the time, and if it doesn't like it when your car is warm, the tuning may be off or the regulator may be going bad.
You may want to learn a little about the WUR, if your car is running the wrong mixture, it may work when you are cold but not when you are hot.
Not trying to send you on a wild goose chase here, just a consideration. Always look for the obvious problems first, and your fuel AFR mix and the WUR are obvious starting points.
maybe somebody smarter than me will chime in about this possiblity.
You may want to learn a little about the WUR, if your car is running the wrong mixture, it may work when you are cold but not when you are hot.
Not trying to send you on a wild goose chase here, just a consideration. Always look for the obvious problems first, and your fuel AFR mix and the WUR are obvious starting points.
maybe somebody smarter than me will chime in about this possiblity.
07-09-2007, 01:56 PM
#4
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Thread Starter
Bummer! I was hoping it would be more simple ... from what I know, those are complex and expensive to replace.
The odd thing is, the stopping motion is a key in causing the idle to stumble or stall. I tried it several times and the results were consistant. I wonder how the WUR could be affected by a stopping or turning g force? It's a self contained unit, right? On the other hand, how could an ignition module faulter in the same way? Very strange.
I think to keep it simple at first, and since I heard the Permatunes do have thermal failure problems, I will replace the Permatune with the MSD and check all the connectors, fuses and wiring that goes along with it. If it still dies, then I will take a look at the fuel pumps, WUR ect... things I am less familar with.
The odd thing is, the stopping motion is a key in causing the idle to stumble or stall. I tried it several times and the results were consistant. I wonder how the WUR could be affected by a stopping or turning g force? It's a self contained unit, right? On the other hand, how could an ignition module faulter in the same way? Very strange.
I think to keep it simple at first, and since I heard the Permatunes do have thermal failure problems, I will replace the Permatune with the MSD and check all the connectors, fuses and wiring that goes along with it. If it still dies, then I will take a look at the fuel pumps, WUR ect... things I am less familar with.
07-09-2007, 02:21 PM
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You also will need to make sure your tachometer works when you hook up the MSD. They do sell a adapter to hook up your tach if it doesn't work right with the MSD when you first set it up. You need to do a little leg work and make sure that your current tach will work with the MSD you have. It may be just a problem for early cars like mine, which have a different tach signal. Don't know about an 82 euro. Might be fine.
Having a WUR looked at is no big deal. Detach it and send it to Brain Leask, and he'll let you know what the deal is. He makes them adjustable.
But I am not suggesting that your WUR is the problem, just a consideration at this point.
If you are up for changing out the ignition system, make sure you know how the MSD installs, there is some advice about it at this board if you do a search on MSD. A930Rocket is one guy who has left some diagrams about installing the MSD correctly on a couple threads here. Do a search before you start in on your project.
Having a WUR looked at is no big deal. Detach it and send it to Brain Leask, and he'll let you know what the deal is. He makes them adjustable.
But I am not suggesting that your WUR is the problem, just a consideration at this point.
If you are up for changing out the ignition system, make sure you know how the MSD installs, there is some advice about it at this board if you do a search on MSD. A930Rocket is one guy who has left some diagrams about installing the MSD correctly on a couple threads here. Do a search before you start in on your project.
07-09-2007, 03:24 PM
#6
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Thread Starter
ok, thanks for the tips on both the MSD and the WUR.
I used to install MSD units on Muscle cars, but I know the Porsche is a whole different animal... I'll do a search and see if I can find a write up or a guide.
I used to install MSD units on Muscle cars, but I know the Porsche is a whole different animal... I'll do a search and see if I can find a write up or a guide.
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07-09-2007, 11:17 PM
#8
Instructor
Thread Starter
Originally Posted by nathanUK '81 930 G50
Make sure you don't have any air leaks at all too.
Thanks, I checked and it's all in good shape
I pulled the Permatune SC911 module out and went through the bench test. Everything ohms out, but pins 1 to 4 should read 3,300 ohms and it is open. I checked with a second meter, same thing. I guess I'll call Perma-tune tomorrow and see what they say unless someone here knows something about it.
