Ford Cmax 1.6DCi 2005. Garage recently changed cam belt and refurbished injectors as fumes coming into car. Fixed the exhaust gas smell but car lacking power and fuel consumption fallen through the roof from 52 mpg to 34mpg - sluugish on acceleration but otherwise as smooth as silk. They have re-checked evrything (not cam belt) and reset the computer. No difference. Anyone have any ideas? For instance, is it possible the cam belt has not been put on properly and the timing is out?

thats possible, or the refurb injectors are not very well refurb'd. If they arent sealing properly then it will suck more air in, making it more inefficient, and if the injector isnt spraying properly, then the mist wont compress and pop...

Take it back to the dealer, as they should have offered you a warranty on this fix. I would ask for the injectors to be recoded and rested properly as a courtesy of the bill you would have paid to get it sorted in the first place...

Thanks James. I have to take it for a long run tomorrow so will see if there is any improvement - but it is running ever so smoothly - no misfire or leaking fumes.

Meant to add that I have taken it back to the garage and they have checked the injector wiring/connections and they have had it on their computer. They did not take the injectors out to check them though. But if any one was faulty would that not make the engine misfire or, at the very least, run roughly?

not necessarily, it depends on the level of degradation. if its only 1% faulty you wont really notice, 20% may feel lumpy 50% may feel misfire etc.

Disconenct the battery for a half hour, and then start again. Run the car for a good few drives, and see if the economy improves.

I'll take that advice - many thanks!

how did it go?

how did it go?

Sorry for delay. Been away for some time! One of the injectors is now leaking fuel! Taking it to another garage. No torque before 1800revs, sluggish going up hill - never before have I had to change down to third going up a certain hill! Max MPG 50 on long run. Down to 34 urban. It is no pleasure to drive anymore Jeebo!

Ouch, and unfortunately injectors are not the cheapest of parts to replace!

I would suggest you start calling round a few scrapyards, see if they have any CMAX' in stock and see how much they want for the injectors...