Land Rover Repair: discovery td5 engine misfire, discovery td5, waste gate

Question
Hi John
I have a 2003 discovery td5. I bought it from a lr dealer with 2000 miles on had it serviced 12000 and 24000 miles at the dealer it has now been back about 6 times with a intermitant missfire at about 3000 rpm.when you start up in a morning i can tell its either a good day or a bad engine day, on the motorway it is kicking all the time when held at a constant speed. when it is running well it flys with pure power. the bad days it feels as if it is off a cylinder ( if it was a petrol you would say it was a fuel or plug breaking down ) when going up a long hill its as if it needs to clear a blockage and the hole vehicle shudders.
Its been back to the dealer, I know one of the mechanics and it did it to him at about 4000rpm it felt like the engine was about to totaly fail the dealer now wants to put on it, after loads of tests a new turbo and ecu unit. what do you think, i see from another email you said about injecters and pump. many thanks
Tony Fletcher
bits4cars.com  

Answer
Tony,

a TD5 owner told me about a similar problem.  He stated that the fault turned out to be a sticking turbo charger waste gate modulator. It was stripped and cleaned and the associated pipes were blocked as well.

This could be your problem too!  

ECU is $@##$ expensive.  Don't go that route unless you absolutely have to.  Why dealers are so easy with our money...I'll never know.  Rarely is it the ECU especially on a 2003.

It really sounds like an exhaust related problem.  Could very well be a waste gate problem.


I wish you the best of luck with this one.  

JohnMc