Technical Multipla throttle problem

[tomo256]

Hi Guys.
My Multipla JTD 1.9 has developed an intermittent fault, occasionally on starting the engine it will tick over nicely but depressing the throttle has no effect on the engine revs, but if you continually hold the throttle down for approx 5 seconds the engine suddenly responds and the revs quickly increase whilst sending a plume of black smoke out of the exhaust and leaving a sooty deposit on the floor. The car will then drive normally for a few days and then the same thing will happen again. I have replaced the diesel filter and to be quite honest the car did seem to improve slightly but it has happened once again tonight. I have been reading on the forum about the EGR on Multiplas and was wondering if this could be the problem, any advice will be gratefully recieved.

Regards
Martin

 

[spitfireboy]

Hi Martin. I have the exact same problem. Sometimes it will only tock over for several days then throttle restores. .. a few days latet power vanishes again. No throttle response. I have cleaned my egr, no use. Then blanked it off. This gave more power when it worked ok. I then bought a computer scanner which couldn't find any faults but would remove the little red injector light fault on my dash but then when presding throttle it would come on again still with no throttle available. I have even replaced the throttle potentiometer which gave strange result of partial power return then full power after a few days and then back to cack no throttle! !?
My next move was three stages...
First to change fuel filter
Second to look for siezed butterfly in injection system.
Then if that doesn't work. ..
Change the lying on board fuel management computer if its possible? ?
I wish I could tell you a sure fix but im guessing myself!! :banghead:
Does anyone have any ideas?

 

[widemouthfrog]

Check the white connector for the potentiometer. This is known to have flaky contacts and several people here have ended up binning the connector altogether and soldering the wires. Some WD40 and repeated pulling apart/pushing together of the block is usually enough to sort it out.

 

[spitfireboy]

Thanks for that wide mouth frog. I will try it. James.