SC '93 Stalls @ low idle, runs a little rough
#18
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Hi Guys.
This car started out as a product of Erik Munk. Devek later got their hands on it and got it all working. Or something like that.
So, not a Murf setup but similar to my old Stage 2 in a lot of ways. I don't know what the car has in it for chips.
Question:
Does the car cough black smoke out the tailpipe when trying to save it from dying at idle? This would indicate an airleak down stream of the MAF. Sounds like the problem slowly came on and when the air leak got worse, obviously so did the running condition of the engine.
I should also add that this problem is exagerated if the TPS idle switch is not working. The LH doesn't know the throttle is closed and will keep firing the injectors.
This car started out as a product of Erik Munk. Devek later got their hands on it and got it all working. Or something like that.
So, not a Murf setup but similar to my old Stage 2 in a lot of ways. I don't know what the car has in it for chips.
Question:
Does the car cough black smoke out the tailpipe when trying to save it from dying at idle? This would indicate an airleak down stream of the MAF. Sounds like the problem slowly came on and when the air leak got worse, obviously so did the running condition of the engine.
I should also add that this problem is exagerated if the TPS idle switch is not working. The LH doesn't know the throttle is closed and will keep firing the injectors.
#19
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"Hammer does not work and flash codes do not work (Andrew good call).
Disconnecting the MAF first to see if anything changes.
Then swapping the MAF from the other GTS.
Back with the results."
Disconnecting the MAF first to see if anything changes.
Then swapping the MAF from the other GTS.
Back with the results."
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Last edited by ROG100; 04-05-2010 at 12:35 PM.
#20
Does the car still have the stock boot that connects the throttle to the MAF? Could have split that boot, or if it has the stock breather setup, it may have blown the "Y" out of the passenger side of the boot causing the rough running?...
#22
I'm just suggesting looking at the boot since the rear turbo guy up here had similar symptoms..and it ended up being his boot.. it was literally cracked apart..but it was only visible when pulled and then examined closely. He ended up getting an aftermarket silicone boot to cure the stocker one from blowing apart.
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If the procedure described by Andrew is correct, the flash codes are not working.
Going to Wikepedia to identify a 10 mm wrench then proceeding to remove MAF. This should be quite humorous.
Going to Wikepedia to identify a 10 mm wrench then proceeding to remove MAF. This should be quite humorous.
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Originally posted by Tim Murphy
Yes, lots.
On another note I found something suspiscous. See Photo.
When we were trying to get the MAF to stay on we put ty wraps on the ears to cinch it down. Note the pinched black hose; this can't be helping anything even if it's not significant. I'll fix this first and see what happens. What is the black hose, anyway?
Question:
Does the car cough black smoke out the tailpipe when trying to save it from dying at idle? This would indicate an airleak down stream of the MAF. Sounds like the problem slowly came on and when the air leak got worse, obviously so did the running condition of the engine.
Does the car cough black smoke out the tailpipe when trying to save it from dying at idle? This would indicate an airleak down stream of the MAF. Sounds like the problem slowly came on and when the air leak got worse, obviously so did the running condition of the engine.
On another note I found something suspiscous. See Photo.
When we were trying to get the MAF to stay on we put ty wraps on the ears to cinch it down. Note the pinched black hose; this can't be helping anything even if it's not significant. I'll fix this first and see what happens. What is the black hose, anyway?
#27
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Cut the tie wrap and disconnect the MAF as we discussed.
Tie wrap can go back on again if need be but this time not trapping the hose/wire.
Tie wrap can go back on again if need be but this time not trapping the hose/wire.
#28
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Cut the tie wrap, massage the hose to "uncrush" it, start/drive it is and see before you mess with the MAF.
BTW, as I mentioned before, we have a professional solution for the MAF/Hose blow-off issue (I'm sure Murf has one too) that would be a lot better than the "solution" shown in that pic.
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Last edited by DR; 04-05-2010 at 02:12 PM.
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Update - Randy has the MAF off and is going to get a mirror so he can inspect the state of the elbow.
Unfortunatly he is stuck using a local mechanic who does not have any real knowledge about the 928.
Hence the tie wrap around the vacuum hose.
Getting a mirror is an hour round trip so be patient until he gets back.
Unfortunatly he is stuck using a local mechanic who does not have any real knowledge about the 928.
Hence the tie wrap around the vacuum hose.
Getting a mirror is an hour round trip so be patient until he gets back.