No power - engine just runs at tickover

[mutley]

Our 55-reg i-CTDI doesn't seem to like the summer! Last year it had loads of problems with power which turned out to be the EGR valve. It now has an intermittent fault where the throttle becomes ineffective and the engine just ticks over and doesn't respond to movement of the accelerator pedal. The garage has replaced the throttle position sensor but the problem has persisted. It's not showing any codes / lights.

Any ideas?

Thanks

 

[F6HAD]

Hi Steve, can you temporarily block your egr valve and see if it revs..

 

[mutley]

Hi Fahad

This problem is very different to the EGR problem we had - with the EGR there was a general loss of power, and the engine would rev - albeit not as well as usual. With this it is as if there is no connection between the accelerator and the engine. Obvious candidates are the TPS (which has been changed) or an electrical fault somewhere between the TPS and the ECU or an ECU fault - if anyone has had a similar issue it would be useful to know what the cause was so that we have somewhere to start looking.

 

[F6HAD]

I have seen this before with an egr.

Have you changed the Accelerator Pedal Position Sensor or the Throttle Position? They are different things

 

[mutley]

Don't know which the garage changed - will have to check.

Turns out the problem was caused by the car overheating - a tiny leak in the radiator resulting in gradual loss of coolant. Garage found it when they kept and ran the car for a couple of days.

Oddly enough the car used to smoke like mad under heavy acceleration, now its as clean as a whistle all the way up to the limiter - very odd, not that I'm complaining!

 

[F6HAD]

Maybe also a leak in the intercooler which was
Solved when they replaced the radiator and put all the pipes back on correctly

Also if the car was overheating I would expect some error codes