996 TTTrouble - help needed please
Discussion
turboguru said:
when I say loses traction I mean the PSM takes over all the time when I dont think it is needed so i wondered if the power wasnt being put down smoothly due to the bad MAF? I guess I do the MAF and then if that doesn't fix it look at it again
why not go to an opc and get them to hook the car up to a diagnostics machine, that will tell you what the fault code / fault is - before you waste a few hundred on a replacement maf
Bennno
When did you last have the plugs changed? modded cars can run a little hotter and the plugs don't seem to last as long. I've had similar problems a little while back (mine's a West tuning modded one) the symptoms of a slight misfire and lower boost (which can look like a traction control issue) and will not trigger any diagnostics on the ECU I changed the plugs and it ran like a dream again - as people have already said it could be a MAF or the hoses but it could also be the plugs if they haven't been done recently, good luck it shouldn't be too serious and I wouldn't have the OPC pul your pants down until you've seen a good indi!
turboguru said:
Right the new MAF has sorted it even better than I could imagine! I gave her a good caining and saw 1.3 bar in 4th and 1.0 in other gears with no traction issues, minimal engine searching, smoother at low speeds!! Its like a new car! Well worth it - happy now!!
Glad you got it sorted! you should be boosting 1.0 bar and the 1.3 is just a spike (hope!) k16's ain't good for 1.3 bar, lol
bennno said:
thats odd, the MAF's played up on my M5 and the BM dealer knew within 2 minutes by hooking the diagnostics up and printing out a fault code. its odd that an OPC couldnt detect a faulty MAF via OBD!!
Bennno
I bet the OPC knew as well. But they knew it was modified, and being a synic I don't think they appreciate the cars being modified by 3rd parties and therefore are as unhelpful as possible. The diagnostic would have told them its a MAF fault.
R. (Angry old man)
I have a Q :
If your MAF is "on the way out" ie not triggering any dash lights etc, but you find the car not running right & suspect the MAF, can an OPC diagnostic tell you there is an issue with it, that its on the way out, or does the MAF have to be completely knackered for it to be picked up by the diagnostics ?
R.
If your MAF is "on the way out" ie not triggering any dash lights etc, but you find the car not running right & suspect the MAF, can an OPC diagnostic tell you there is an issue with it, that its on the way out, or does the MAF have to be completely knackered for it to be picked up by the diagnostics ?
R.
my m5 was running lumpy and felt slightly sick.
the tests got done at the BMW garage in Le Mans, despite my little knowledge of French or obd it seemed as simple as he wheeled the cart up to the car, pressed a couple of buttons and within seconds he was shrugging his shoulders, tutting, rubbing is hands and saying all (2 or 4?) MAFS needed replacing.
So I guess it should be obvious from the diagnostics. He also told me I almost ran out of petrol a couple of days previously so they seem all knowing.
Bennno
rumplestiltskin said:
I have a Q :
If your MAF is "on the way out" ie not triggering any dash lights etc, but you find the car not running right & suspect the MAF, can an OPC diagnostic tell you there is an issue with it, that its on the way out, or does the MAF have to be completely knackered for it to be picked up by the diagnostics ?
R.
If your MAF is "on the way out" ie not triggering any dash lights etc, but you find the car not running right & suspect the MAF, can an OPC diagnostic tell you there is an issue with it, that its on the way out, or does the MAF have to be completely knackered for it to be picked up by the diagnostics ?
R.
The tester could indicate that there was an issue with the MAF but not necessarily via a fault code, if the sensor was still working within allowable tolerances. It would need some analysis of the values being used by the control unit - thats what'll take the time...
As I suggested in a previous post, an air leak behind the MAF then incorrectly measured air is entering the engine. This could cause a PSM fault before it causes an engine fault due to the affect that it would have on delivered torque figures that the PSM uses - which may be why your PSM keeps intervening.
Remember, you are getting low boost pressure values - measured by a pressure sensor in front of the throttle plate not by a MAF sensor!!! Does low boost not indicate a leak???
If you push the values enough, you may get a PSM fault before you get an engine fault, based on the fact that unmeasured air would be entering the engine (ie drive the nuts off it and see what happens)...
Get the pipework after the intercoolers checked out!!!!
Just a thought...
turboguru said:
Right the new MAF has sorted it even better than I could imagine! I gave her a good caining and saw 1.3 bar in 4th and 1.0 in other gears with no traction issues, minimal engine searching, smoother at low speeds!! Its like a new car! Well worth it - happy now!!
I'll shut up then....
Well fixed!!!
Glad you got it sorted! you should be boosting 1.0 bar and the 1.3 is just a spike (hope!) k16's ain't good for 1.3 bar, lol[/quote]
Cheers - its only showed 1.3 on overrun and normally 0.9 - 1.0 is the maximum but no traction issues either now, it drives the best it ever has and is like a different car! think its time i took it for another blast!!
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