406 1.9 TD Throttle Position Potentiometer

Gastropod · Unread post by **Gastropod** » 21 Feb 2006, 23:55

Does anybody know where I can get a throttle position potentiometer for a 1996 Pug 406 1.9 TD? with a Bosch injector pump?

Thanks,

Mike

rayc · Unread post by **rayc** » 25 Feb 2006, 20:43

Has it got one?

Gastropod · Unread post by **Gastropod** » 25 Feb 2006, 20:55

Course it has! I wouldn't be looking for one otherwise!

The pot is at the top of the quadrant on the injector pump where the throttle cable ends.
The old pot has a worn out track and I am pretty sure this is the cause of the tacho dropping to zero on teh overrun.

Dave Burns · Unread post by **Dave Burns** » 25 Feb 2006, 22:24

Get a price for it from a main dealer and then go to a reputable diesel fuel injection specialist, other than a used one (probably also knackered) I can't think where else you will get one.

Could be the cause of the tacho going down but should almost certainly be accompanied by the engine management light.

The ecu will provide a tacho signal from both the injector lift sensor and the tdc sensor in the bell housing, disconnect them one at a time, if the tacho goes down when one is disconnected it means the other is not working, when they are both good the tacho keeps reading normally when either one of the sensors are disconected.

Dave

Gastropod · Unread post by **Gastropod** » 25 Feb 2006, 23:50

Great! Thanks.

I am pretty sure that this problem is directly related to this pot. I have tested it with a multimeter and find a dead spot at the beginning of the track. Also, when the engine is idling, the tacho reads okay. When thje engine is under load, i.e I am applying some throttle, the tacho also reads okay. It is just the overrun when I have my foot off the throtle, and thus the pot is in the dead part of its track, that the tacho drops to zero.
There is no ecu warning though. Strange.
This fault does not seem to affect performance or economy.

KevMayer · Unread post by **KevMayer** » 22 Mar 2006, 21:55

I have a problem with the throttle position sensor on the Bosch pump on my Xantia 1.9 turboD.

I too found a dead spot on the resistance measurement around the low throttle setting. I have had an issue with timing for some time which I always suspected was due to this sensor. It just never seemed right. I had a quote for over 200 quid for a new position sensor from Citroen.
Citroen breakers would only sell me the complete pump. They wouldn't break it down to sell me just the sensor.

In the end, I purchased an older Bosch pump off ebay for 10 quid and fitted it. it has mechanical timing, no ecu control at all.

Since fitting the older pump I have much better pulling power and a few mpg extra (used to get 36 mpg all the time, now get very repeatable 39 mpg).