Surging when cold; codes p0102, 5525

[Jerry996]

I have a 1999 Carrera 4 that has started surging and bogging down at low speeds when cold. It usually triggers the PSM and ABS lights within 3 minutes of driving. You can hear the engine surging at idle, it probably hunts up and down about 50-100 rpm's. My independent pulled codes P0102 and 5525 from the ECU. I replaced the MAF with a new unit (and air filter), cleaned the airbox and no change. Once the car warms up there are no problems, no surging and no hesitation. Restarts clear the ABS and PSM lights and they don't return unless the engine is started from cold. Do I need to disconnect the battery to reset the ECU or will this problem clear itself or am I dealing with something else. Any advice is much appreciated.

Jerry

[rb101]

I think you still have MAF issues. I think the ECU uses the temp sensor in the MAF to determine A/F mixture until it warms up, and it's off (or disconnected) causing bad cold running. You might have a wiring issue in the MAF harness.

[mhariush]

I just got the P0102 error code too, combined with P0446.

What was the outcome of your error?

[JFP in PA]

Originally Posted by Jerry996

I have a 1999 Carrera 4 that has started surging and bogging down at low speeds when cold. It usually triggers the PSM and ABS lights within 3 minutes of driving. You can hear the engine surging at idle, it probably hunts up and down about 50-100 rpm's. My independent pulled codes P0102 and 5525 from the ECU. I replaced the MAF with a new unit (and air filter), cleaned the airbox and no change. Once the car warms up there are no problems, no surging and no hesitation. Restarts clear the ABS and PSM lights and they don't return unless the engine is started from cold. Do I need to disconnect the battery to reset the ECU or will this problem clear itself or am I dealing with something else. Any advice is much appreciated.

Jerry

P0102 is a shorted MAF wiring issue, P5525 is a data communications problem with the DME.