ABS/PSM Issue (Not your normal problem...) Please help!
#16
02-20-2009, 09:19 AM
So Chris, I need some more info. What mods do you have? I can't tell from your sig (other than it is a monster)? Do you have rails and injectors or just FPR? Have you talked to Tony or Stephen? Have you tried to flash back to stock and run it?
#17
02-20-2009, 09:24 AM
One thing you brought up in that other PSM thread that makes me wonder is what exactly does PSM do to control wheel spin? Does it play with the throttle, brakes, or timing?
I've talked to Tony and he suggested trying a MAF first and if not another DME. I am having trouble finding a MAF for a decent price, but I did find a good deal on a 2nd DME. I've also emailed Stephen, but I think he has been busy so I have not heard from him yet. I'd email Todd K, but I don't think he would want to deal with a non-customer having problems (which I understand because it could be a complicated problem and a reply or call may take awhile and I know he stays busy).
Last edited by Powell; 02-20-2009 at 09:37 AM.
#18
02-20-2009, 09:38 AM
Just read a thread where someone put the post up Jimmer made where Porsche or someone explains the PSM system and how it works.
The only thing different to when the throttle body shut (and the lights came on for the first time) was the boost was at like 17.8lbs which is my old pump gas boost. Could wheel spin with PSM on freaked out the PSM system and caused it to go haywire.
I saw another post about someone who got a FVD tune and his did it also. I never found a resolution thread and the user no longer posts here.
The only thing different to when the throttle body shut (and the lights came on for the first time) was the boost was at like 17.8lbs which is my old pump gas boost. Could wheel spin with PSM on freaked out the PSM system and caused it to go haywire.
I saw another post about someone who got a FVD tune and his did it also. I never found a resolution thread and the user no longer posts here.
#19
02-20-2009, 09:46 AM
Got me thinking....have you tested the rate of turn sensor (steering angle sensor)? Perhaps it is bad or needs to be recalibrated....this will need to be done if you replace the control unit as well. Have you read codes with PST2 or PIWIS? You might need some more advanced diagnostics.
PSM follows two fundamental control strategies: First, it offers the well-known concept of longitudinal control with ABS anti-lock brakes, anti-spin control and the Automatic Brake Differential keeping the car smoothly on course when accelerating and applying the brakes on a straight or in bends.
Second, PSM also offers lateral or transverse control keeping the car reliably on course even when subject to substantial lateral forces in a bend. The corrections required for this purpose are provided by the specific, carefully controlled application of the brakes.
It does not directly control power TMK.
PSM follows two fundamental control strategies: First, it offers the well-known concept of longitudinal control with ABS anti-lock brakes, anti-spin control and the Automatic Brake Differential keeping the car smoothly on course when accelerating and applying the brakes on a straight or in bends.
Second, PSM also offers lateral or transverse control keeping the car reliably on course even when subject to substantial lateral forces in a bend. The corrections required for this purpose are provided by the specific, carefully controlled application of the brakes.
It does not directly control power TMK.
#20
02-20-2009, 09:50 AM
Got me thinking....have you tested the rate of turn sensor (steering angle sensor)? Perhaps it is bad or needs to be recalibrated....this will need to be done if you replace the control unit as well. Have you read codes with PST2 or PIWIS? You might need some more advanced diagnostics.
PSM follows two fundamental control strategies: First, it offers the well-known concept of longitudinal control with ABS anti-lock brakes, anti-spin control and the Automatic Brake Differential keeping the car smoothly on course when accelerating and applying the brakes on a straight or in bends.
Second, PSM also offers lateral or transverse control keeping the car reliably on course even when subject to substantial lateral forces in a bend. The corrections required for this purpose are provided by the specific, carefully controlled application of the brakes.
It does not directly control power TMK.
PSM follows two fundamental control strategies: First, it offers the well-known concept of longitudinal control with ABS anti-lock brakes, anti-spin control and the Automatic Brake Differential keeping the car smoothly on course when accelerating and applying the brakes on a straight or in bends.
Second, PSM also offers lateral or transverse control keeping the car reliably on course even when subject to substantial lateral forces in a bend. The corrections required for this purpose are provided by the specific, carefully controlled application of the brakes.
It does not directly control power TMK.
I'll try the steering position and see if that helps. I read that thread about the guys 3.8ltr that did it and FVD recommended that too. I'll go out and try it here in a second.
#23
02-21-2009, 01:08 PM
Update to the problem. Finally turned the boost back up to 22psi last night on race gas. As soon as the car goes into boost it starts breaking up really bad. I finally got it to stop breaking up at about 18psi. So it's either the DME or the MAF.
#24
02-21-2009, 03:40 PM
I kept getting PSM/ABs lights on my car and took it to Loren at 911 Design. He went through it again and again, but couldn't figure it. Finally he replaced the throttle body and that solved it. He said the throttle bodies go bad every now and then. Good luck.
Last edited by Onetime; 02-21-2009 at 05:46 PM.
#25
02-21-2009, 05:40 PM
PSM
Sometimes a loose connection or damaged when going to RWD? Check sensors in each wheel?
Boost
Are your heads starting to lift or the Gaskets getting old? Did you check your fluids to see if there is any leakage?
MAF
I have an extra MAF at Akram's if you like to compare? I have that is tuned just for Todds program and one just for street driving.
Electrical
Any possibilities it is your plugs or connections?
Good luck
Robert
Sometimes a loose connection or damaged when going to RWD? Check sensors in each wheel?
Boost
Are your heads starting to lift or the Gaskets getting old? Did you check your fluids to see if there is any leakage?
MAF
I have an extra MAF at Akram's if you like to compare? I have that is tuned just for Todds program and one just for street driving.
Electrical
Any possibilities it is your plugs or connections?
Good luck
Robert
#26
02-21-2009, 08:42 PM
These gremlins sure are a pain in the ****....
#27
02-21-2009, 11:15 PM
PSM
Sometimes a loose connection or damaged when going to RWD? Check sensors in each wheel?
Boost
Are your heads starting to lift or the Gaskets getting old? Did you check your fluids to see if there is any leakage?
MAF
I have an extra MAF at Akram's if you like to compare? I have that is tuned just for Todds program and one just for street driving.
Electrical
Any possibilities it is your plugs or connections?
Good luck
Robert
Sometimes a loose connection or damaged when going to RWD? Check sensors in each wheel?
Boost
Are your heads starting to lift or the Gaskets getting old? Did you check your fluids to see if there is any leakage?
MAF
I have an extra MAF at Akram's if you like to compare? I have that is tuned just for Todds program and one just for street driving.
Electrical
Any possibilities it is your plugs or connections?
Good luck
Robert
If you have an extra standard Porsche MAF would you mind asking Akram if I can install it on my car and test it really quickly. It should make the problem go away if I reset the computer and install the MAF at the same time. If that is it I will know what to order exactly. If that does not fix it, then it's on to check your other suggestions.
Akram is the first person I went to when this came up and he gave me a list of ideas, but even he said it was a really weird problem LOL!
PS. Was in The Woodlands tonight visiting a friend of mine, but I don't have you or Chris's number. Next time I come up there I want to check out the blue car! I want to go for a ride in it. I drove mine out there tonight because it's been awhile. It feels good with these external wastagates being able to turn the boost down to 13psi or so and not having to worry about always having race gas!!
Last edited by Powell; 02-21-2009 at 11:17 PM.
#29
02-23-2009, 08:00 PM
So I've been doing a lot of searching in all the old threads about PSM/ABS issues and it's usually one of two things. First its the MAF, but it almost always has a CEL and the car runs bad. The other is the brake light switch which makes the brake lights not work. My problem is not either one... So I'm kinda left clueless and so is the dealer. They have a few ideas what can be wrong, but nothing definite.
It all started a few days ago after about 100-110miles after getting the car running again. Its about 55* outside and the car is warmed up. I roll into boost in 2nd gear and right as it gets to 1.0bar or so (I had it set at 1.1) the throttle body shuts and the PSM/ABS light comes on. There was no CEL, but I didn't even think about that part. So I was like damn my MAF blew up. I pull over about a mile down the road and hook up my Durametric to check to see whats up and possibly reset any codes if there was just a hiccup in the DME. I goto DME and then goto the Fault tab... Nothing is there, it has 0 Faults and you can reset it all you want and check again and there is nothing. I go to ABS/PSM and there is an error, but no code number. I don't remember exactly what it said but when I went to reset it I get an error that says cannot connect to DME. I kept trying that and that was the error I kept getting.
I spent a little while resetting the battery multiple times including doing a full drain on the electrical system. Within 5-10 seconds of it running the light comes back on. So I take it to the dealer and they come back and tell me that the DME is showing there are no errors, but the ABS/PSM system which works along side of the DME is detecting there are some errors in the DME. So they tell me it's either one of three things. The first is there is something wrong with the tune (but I've had it over a year without a problem like this). The second is that the DME was actually failing or had an error in it. The third is that the ABS/PSM unit was actually bad itself. The only thing about the third is that if you pull the fuse for the PSM/ABS it brings up the ASR light also so I think that helps eliminate that.
The funniest thing about it is that the car runs PERFECTLY fine, feels smooth as can be in boost, the air/fuels are perfect, the idle is perfect, etc.. So it really rules out the MAF in my opinion.
So basically I am at a loss. I am going to order a new DME and try that first I guess because the ABS/PSM system is not cheap. Has anyone ever seen this issue?? I need to get it fixed ASAP, because the car cannot pass state inspection and it went out last month
Thanks,
-Chris
It all started a few days ago after about 100-110miles after getting the car running again. Its about 55* outside and the car is warmed up. I roll into boost in 2nd gear and right as it gets to 1.0bar or so (I had it set at 1.1) the throttle body shuts and the PSM/ABS light comes on. There was no CEL, but I didn't even think about that part. So I was like damn my MAF blew up. I pull over about a mile down the road and hook up my Durametric to check to see whats up and possibly reset any codes if there was just a hiccup in the DME. I goto DME and then goto the Fault tab... Nothing is there, it has 0 Faults and you can reset it all you want and check again and there is nothing. I go to ABS/PSM and there is an error, but no code number. I don't remember exactly what it said but when I went to reset it I get an error that says cannot connect to DME. I kept trying that and that was the error I kept getting.
I spent a little while resetting the battery multiple times including doing a full drain on the electrical system. Within 5-10 seconds of it running the light comes back on. So I take it to the dealer and they come back and tell me that the DME is showing there are no errors, but the ABS/PSM system which works along side of the DME is detecting there are some errors in the DME. So they tell me it's either one of three things. The first is there is something wrong with the tune (but I've had it over a year without a problem like this). The second is that the DME was actually failing or had an error in it. The third is that the ABS/PSM unit was actually bad itself. The only thing about the third is that if you pull the fuse for the PSM/ABS it brings up the ASR light also so I think that helps eliminate that.
The funniest thing about it is that the car runs PERFECTLY fine, feels smooth as can be in boost, the air/fuels are perfect, the idle is perfect, etc.. So it really rules out the MAF in my opinion.
So basically I am at a loss. I am going to order a new DME and try that first I guess because the ABS/PSM system is not cheap. Has anyone ever seen this issue?? I need to get it fixed ASAP, because the car cannot pass state inspection and it went out last month
Thanks,
-Chris