Throttle position sensor

kevo · Post by **kevo** » Tue Mar 18, 2008 9:12 pm

Been having trouble with gears for a while now,2.5 auto. When i first start the bongo it will not change out of first until it has been running for about 20 minutes or so. A couple of garages couldnt shed any light on the problem or were reluctant to try and find out,so i took the beast a place that only does gears,he done a diagnostic on it with one of those fancy little gadgets and it come up with faults coded 16 and 12. Now in his book these were throttle position sensor and exhaust gas recirculation/valve position sensor. I dont really have a clue what these mean and with him only dealing with gears he recomended getting it seen to by a diesel fitter as he seems to think that these are engine problems. He did say that once these are sorted out he is 95% sure the gears will work ok.
Does anybody know anything about these problems and how to go about fixing them so that when i take it in i am not going there totally clueless. Any help would be greatly appreciated.

Bongopatrol · Post by **Bongopatrol** » Tue Mar 18, 2008 11:35 pm

Hi Kevo
I had a problem with my auto box and on getting it repaired by Dunnings Automatics in Weymouth Dorset they told me the most likely cause for damaging my box was the throttle position sensor.
If it is set wrong it has an effect on the oil pressure in the gearbox causing gear change problems and in my case burning out my auto clutches.
When driving you should feel positive jerks with ever change and not like mine was havinga slight slip between changes so when I fitted my new box I had to adjust the throttle position sensor accordingly.
Operantly some garages adjust them for emission reasons to get them through MOT when they first arrive in this country.

bigdaddycain · Post by **bigdaddycain** » Tue Mar 18, 2008 11:39 pm

Hi Kevo, fault code 12 is "open circuit" fault in the T.P.S.

Do you have a flashing hold light,or rev counter reading zero at speed too? If so, it may be a dodgey connection with the speedo conversion chip, if you have one fitted.

With regards to the T.P.S, try unplugging,then re-plugging the sensor before you throw any money at it,the sensor is situated on top of the fuel pump.

E.G.R is "exhaust gas recirculation" A device intended to improve emissions when new,to conform with the strict emissions rules in japan at the time.

The E.G.R has a sensor that is housed in a dome on top of the EGR pipe,there are three stubborn screws to undo to release the sensor from the housing,these can be troublesome devices at the best of times,and many have blanked,or ditched the egr system completely.

I have removed the egr system on my bongo using the Nick skidmore kit,pm nick to see if any more are available,allans vehicle services also sell an egr blanking kit. Pm doone for more info....

bigdaddycain · Post by **bigdaddycain** » Tue Mar 18, 2008 11:45 pm

Bongopatrol wrote: When driving you should feel positive jerks with ever change and not like mine was havinga slight slip between changes

Mine are nice smooth changes without any evidence of jerking

I can "feel" the gears change,but they are very smooth in operation,the gearchanges are more noticeable on the odd occasion i "kick it down"...

kevo · Post by **kevo** » Wed Mar 19, 2008 8:47 pm

Thanks for the input i will try the tp sensor unplugging/re plugging thing.
I would love to try all kinds but always a bit afraid, because i have not really got a clue thats why this site is invaluable.

bigdaddycain · Post by **bigdaddycain** » Wed Mar 19, 2008 8:54 pm

It's probably worth giving the contacts a clean up whilst at it...

The Great Pretender · Post by **The Great Pretender** » Wed Mar 19, 2008 11:35 pm

bigdaddycain wrote:It's probably worth giving the contacts a clean up whilst at it...

Cillit Bang

Peg leg Pete · Post by **Peg leg Pete** » Thu Mar 20, 2008 3:38 pm

The Great Pretender wrote:
bigdaddycain wrote:It's probably worth giving the contacts a clean up whilst at it...
Cillit Bang

You said that without shouting