156 Throttle Problem

[JamesT99]

Hi

Can anyone throw any light on this ..

I have a 2002 156 2.0JTS, with about 35K miles on the clock. Driving along yesterday, the system flashed up a fault message 'Motor Cotrol System Fault' and the engine sign warning light came on. The tickover became erratic, and then after a few miles it wouldn't rev above about 2500RPM.

Driving it to our local garage this morning, and none of the fault message came up, and it seemed to drive OK. The garage check the diagnostics, and there was a 'Throtle Position' fault logged, which probably means the throttle potentiometer is on the way out, or maybe a loose connection. We didn't do anything else to it. However, I'm now getting a harsh booming sound at higher engine speeds - sounds almost as though there's a hole in the exhaust.

I suspect the original problem has caused another setting in the Engine Management System to be altered in some way. Any ideas ?

[xyyman]

Does sound like the fly by wire throttle potentiometer. Its a sealed unit with a bit of wiring loom attached costs about £160ish.Oh for the days of throttle cables!

Phil

[wombat rick]

I think there was some cases of this happening by the wires to the lambda sensor shorting on the exhaust pipe. See if you can get the car on some ramps and have a really good luck to make sure nothing is touching - or could touch - the exhaust. 156 exhausts more around a fair bit, so you might just get an intermittent problem after some "enthusiastic" cornering or "similar" has caused the exhaust to move further than normal.