Help Loren -Camshaft Control

[DXB_996tt]

Hello,

I had posted this on the TT forum with no luck, I have a MY01 996tt, recently did new GT28 turbo's with injectors and a new tune of course, after the flash the car started misfiring on Bank 2, after checking for leaks in the intake system, changing spark plugs, checking to make sure all connections were good, I hooked up the car to the Durametrics software and found a large variation between Adaptation values in Area 1, between Bank 1 and 2, along with a code P1133. After reading through a post by Loren, excerpt below, it seems I need to "Reset Camshaft Control" anyone have any idea how to do this?

"Possible mechanical causes of faults

Valve lifter chattering.

This is caused by dirt in the valve lifter.

When the Check Engine MIL lights up, a chattering valve lifter may also occur for a certain time. The DME control module registers (sporadic) misfiring at one or more cylinders. The adaptation values of areas 1 and 2 are normal.

Remedy

1. Remove lifter bores, check for damage and blowout oil passages.

2. Replace all valve lifters (engine installed).

3. During the test drive, listen for valve lifter noises.

Camshaft control badly adjusted.

The camshaft control has changed. No chattering noises occur. The DME control unit indicates misfiring for the entire cylinder bank 1 or 2. The adaptation values in area 1 differ in bank 1 and bank 2 (e.g. TRA=0.02/TRA2=0.27), the adaptation values for area 2 are generally normal.

Remedy

1. Reset camshaft control.

2. Road test vehicle. The adaptation values should be normal.

VarioCam does not switch over completely.

Cases have occurred in which the VarioCam of one bank was mechanically faulty. In these instances, the VarioCam had not switched over completely from power to torque valve timing.

An indication of this problem is misfiring detected by the DME control module in the range of 1200 - 1500 rpm occurring in an entire bank. The adaptation values of areas 1 and 2 are normal.

Remedy

1. Replace VarioCam.

2. Road test vehicle."

TIA

[Loren]

Your car is a 996TT - different engine different fault diagnosis.

P1133 Oxygen Sensing Adaptation, Lower Load Range, Bank 2 - Below Limit

Possible fault cause:

♦ Incorrect signal from MAF sensor

♦ Fuel pressure too high

♦ Fuel injector leaking

[DXB_996tt]

Thanks Loren!

Since the issue is on one bank I assume that I can rule out the MAF?

Fuel Pressure shouldnt have changed as the FPR is stock, so I'm left with a leaking injector..... But it seems odd that I would get a misfire for each cylinder on that bank(4,5,6), as opposed to just one of them. <_<

Your car is a 996TT - different engine different fault diagnosis.

P1133 Oxygen Sensing Adaptation, Lower Load Range, Bank 2 - Below Limit

Possible fault cause:

♦ Incorrect signal from MAF sensor

♦ Fuel pressure too high

♦ Fuel injector leaking

[Loren]

If you have OBD II software you should be able to see the MAF air flow readings which will tell you if the MAF is working properly.

A leaking injector is fairly rare but it can happen.

[DXB_996tt]

Loren

I do have Durametric software, my "Hot Film MAF" reading is around 1.40 at idle, and "Mass Air Flow HFM" is around 23....

No idea if these are the correct numbers to be looking at

Thanks Again! :renntech:

If you have OBD II software you should be able to see the MAF air flow readings which will tell you if the MAF is working properly.

A leaking injector is fairly rare but it can happen.

[Loren]

For 996TT it should be:

(warmed up) At idle speed: 16 - 20 ML in kg/h

No load, n=3,000 rpm: 60 - 80 ML in kg/h