8757william

Yes, it was the MAF, finally I can enjoy my car. Everything is working great, thanks for all the help.

I think I found my problem.. When I tested it with the MAF unpluged, the abs/psm lights came on but it reved out in the higher gears without any hesitation or surging! I did it atleast 4 times, hopefully I didint run it lean.. I was surprised to find it was the MAF, because I had no faults pointing to it and I never had the abs/psm lights come on before. It looked fine and I even tried cleaning it. So I already ordered a new Bosch one off ebay $285 cdn shipped. Thanks for all the help, I'll post back in a couple weeks after I get the part and try it. __________________

I cleaned the MAF with the instructions I found on here, but it made no difference. I used my durametric to watch the actual values for the charge pressure and boost pressure, and they moved up and down while I free reved it. And I watched the ambient pressure actual values and it was just a straight line, but I suppose thats what it is supposed to be? I cleared the codes (missfires on 4,5,6) And I took it for a drive, everything is still the same, only at higher rpm (aprox 4500 and up) while accelerating it feels like the power is cutting out, and the rpm's increase very slowly. During idling or normal driving its fine. If I floor it in 6th gear at 60mph it will hold .7 bar and accelerate like it was new. The problem only happens at higher rpm. After the test drive I checked for faults with the durametric but none have come back, it was only a 10 minute drive, but I did encourage the car to act up several times. I also watched the actual valuea for cylinders 1,2,3,4,5,6,misfires on the durametric while free reving it in the garage, no misfires. Today I lowered the engine 2 inches with the instructions I found here and did another boost pressure test. I found a very very small slow leak coming from part no. 996.110.652.70 Venturi tube, it mounts right on top of the aluminum intake pipe beside the charge pressure sensor. So I suppose I should order a new one of those? I have also been wondering about my DV's they are stock, but I cant recall ever hearing any honking sounds, so I dont know if upgrading these could help or not? Any other suggestions are appreciated, thanks for the help so far.

Even though that code has not returned since I cleared it 1 month ago, you still think its possible it could be causing a problem?

It missfired on cylinders 4,5 and 6, if they are all on the same side of the engine, would they all be controled by the same knock senor? Is there a chance I could have a faulty knock sensor or connection on that side??

I cleared the pressure sensor fault code a month ago when I first seen it. And today when I scanned it with the durametric the pressure sensor code was not there, only the missfire codes. Maybe the pressure sensor fault was old news, and had just never been erased. I did a boost pressure test already and it seemed to be fine, that would rule out most of the intake hoses right? Any other suggestions???

The p1136 code I got from my durametric was from about a month ago, and I cleared the code after I wrote it down. Since then I changed the plugs and coil packs, and the car is still doing the exact same thing. So after Lorens sugestion today to get the actual values, I hooked up the durametric and it's now telling me missfires were detected on cylinders 4,5 and 6. (p0300,p0304,p0305,p0306) One time last week the check engine flashed 5 or six times quickly while the car felt like it was missfiring or stuttering, but it quit flashing and never came on since. So I guess I might not have a pressure sensor problem, but what could be causing the missfire codes and this loss of power at WOT above 4500rpm??

Thanks for the quick reply, I assume these sensors are mounted on the intake piping somewhere, one before and one after the turbos. Do you have any tips where I should look to help me find them.

I'm new to this forum, I've been reading posts off it for three months now. It has proved to be very helpful. Three months ago I bought a 01 Turbo and ever since it has had this problem. At full throttle, in 3rd gear and up, once the revs get to 4500 or higher, it will have a sudden loss of power, the revs will climb very slowly it feels like a misfiring or stuttering, like its starving for fuel. Its fine in 1st and 2nd gear through the rev range. But 3rd and up once the revs get higher it happens. When it starts to stutter the boost will usually drop from .6 or .7 down to .4 and stay there. NO check engine light, no trouble lights at all. The car is all stock, No mods. I have already done a boost leak pressure test up to 15psi, and its fine. I have installed new bosch fr6 plugs and updated 997 coil packs. I have removed and visually inspected the MAF, I havent replaced it because from what ive read, when they're bad they turn on psm and abs lights. I have a durametric, and this is what it told me (p1136 Fault code 440 pressure sensor signal comparison charge pressure/ambient pressure signal implausable). I cant find much info on these faults, Do you know what could cause them ??? Thanks for reading, please help if you think you can.