General turbo lag,maybe

[psevans]

hi i have a 1.9 jtd and when it's cold ,starting off it's a pig i go 200yards before the turbo kicks in and then its ok . also even when its warm pulling away from junctions i have to rev it and hope for the best. it was ok up until i had the cam belt changed 10'000miles ago. the temp bars always sat on 4 but since the change it fluctuates between 3and 4. i'm not that mechanically minded and not that well so if you can help me with this i can point the garage in the right direction ..thanks

 

[momoe]

Normally JTD's sit on 3 bars, high cruising speed on motorways might see 4 but 4 all the time is unusual.
Lack of boost could be a number of issues but the obvious one's to check are the boost sensor and it's associated plumbing, turbo boost sensor is fed by a small (normally red) tube from the bottom of the turbo to the boost sensor which should be down to the left of the battery box.
The other thing to check is the relative positions of the camshaft and crankshaft, one tooth out on the timing belt isn't unheard of.

 

[psevans]

thanks i'll have a look over the weekend

 

[Matthen]

4 Is unusal? On ours 3 was unusal, only happened when crusing in that really cold spell last year... Even sat at idle it would hold 4, and had done since we bought it at ~28 miles... Was a JTD 115 though... One of the last of the pre-facelift ones...

 

[widemouthfrog]

Ditto. Late model roundnose JTD115. Hardly ever see anything other than 4 bars. Never seen 5!

 

[psevans]

well the old girl is back the timing was out by one tooth and also the maf sensor was faulty it was giving way too much air so it was running a little cold .the temp now sits at 4 (as it used to ) and it goes like a new car .......thanks for your help now i'm a happy camper once more.