Omega Owners Forum

Chat Area => General Car Chat => Topic started by: mantahatch on 24 May 2010, 09:08:11

Title: Drive by wire
Post by: mantahatch on 24 May 2010, 09:08:11

Sorry to ask about a Seat Alhambra. Dad's car is 2002 1.9 TD and has an occasional fault where you got to accelerate and nothing happens, no increase in engine speed. if he lifts off the throttle and back on again it will sometimes work again, and sometimes requires 3 or 4 attempts.

It is drive by wire (no throttle cable) I am assuming pedal bit is faulty, or bit on injector pump.

Just hoping someone on here may no a bit about it, as replies on the MPV type forum are practically none existant.

Thanks.

Title: Re: Drive by wire
Post by: Kevin Wood on 24 May 2010, 09:57:17

Sounds like it might be the DBW system causing issues. I'd expect some fault codes to be stored if so. Perhaps get an OBDII reader on it?

Kevin

Title: Re: Drive by wire
Post by: mantahatch on 24 May 2010, 11:45:14

Has been on a machine at local auto gearbox specialist. Had a few error codes from before the autobox was changed and these where cleared. Nothing engine wise was recorded.

Thanks

I think it may be a pedal switch problem, as no codes stored and if pedal causing problem, would the system record a it as a fault, What I am trying to say is if the engine does not rev up because it does not receive a signal from the pedal, then engine just stays at tickover with no fault.

I am sure that don't make sense, sorry.

Title: Re: Drive by wire
Post by: henryd on 24 May 2010, 12:16:20

mass airflow sensor can cause this issue as well and does not leave a fault code,normally if you switch off and remove key then restart problem goes away till next time.dbw normally does record a code

Title: Re: Drive by wire
Post by: Kevin Wood on 24 May 2010, 12:32:09

Quote

Has been on a machine at local auto gearbox specialist. Had a few error codes from before the autobox was changed and these where cleared. Nothing engine wise was recorded.

Thanks

I think it may be a pedal switch problem, as no codes stored and if pedal causing problem, would the system record a it as a fault, What I am trying to say is if the engine does not rev up because it does not receive a signal from the pedal, then engine just stays at tickover with no fault.

I am sure that don't make sense, sorry.

Normally DBW systems have a dual redundant pedal position sensor. In other words, two sensors whose output must match for the ECU to respond. This prevents a failure of the pedal sensor causing the car to accelerate out of control!

If a failure occurs, the ECU will detect a discrepancy between the two pedal sensors and fail safe by running only at idle or a fast idle. It will store fault codes in the engine ECU in this instance, though.

Kevin