Focus 2004 1.8 TDCI no power at low RPM

[chap160]

Hi Guys

I have a 2004 Focus 1.8TDCI, Last year the tubo went and we had to replace it. Since then there seems to be a lot more turbo lag than before. Certain roads/junctions/hills that i drive on regulaly i now have to use a gear lower than i did before. For example, in 3rd gear the turbo used to kick in between 1500 and 1800 rpm, now i have to rev over 2000 before getting any boost.  Nothing else was changed when the turbo was replaced and the problem appeared instantly.  Once the boost does come in, its as powerful as it always was so the turbo is working just at a slightly higher rpm. 

Has anyone else experienced this after swapping a turbo? Can anyone suggest what i can look for.  My limited knowledge and looking online points to maybe the wastegate staying open too long at low revs?

Any help would be apprieciated, Thanks.

[Damien]

Your correct in saying Sticky wastegate,also boost could be too low which will give you delay in boost as you did last time.

also common is vacuum and turbo hose pipes,check for splits some really hard to find mind so I good hard look.a split in pipe can give you lack off boost.

[chap160]

Thanks David. Once i am at higher revs, there is plenty of boost so i dont think its a leak as such.  Is there any adjustment on the wastegate to make it close earlier?

[Damien]

You can adjust the wastegate but tbh mate I wouldn't touch it there no real need to mess with this pal,

you could try some egr cleaner n give a clean up the egr if dirty, the flap that opens n closes on throttle response could be sticking so when you press harder on the peddle to increase more revs then it's forcing it open instead of just opening freely if you know what I mean.

 

[chap160]

1 hour ago, Damien said:

You can adjust the wastegate but tbh mate I wouldn't touch it there no real need to mess with this pal,

you could try some egr cleaner n give a clean up the egr if dirty, the flap that opens n closes on throttle response could be sticking so when you press harder on the peddle to increase more revs then it's forcing it open instead of just opening freely if you know what I mean.

 

Ill have a look at cleaning the egr valve thanks.  What confuses me is that the problem occurred instantly after changing the turbo rather than over time, which is why i thought its was something with the turbo/wastegate.  Cheers mate.

[Damien]

No worries mate, could be a faulty turbo just bare that in mind too if just been replaced 

[chap160]

22 hours ago, Damien said:

No worries mate, could be a faulty turbo just bare that in mind too if just been replaced 

Hope not, took me and me dad 6 hours to change it!

[chap160]

Hi Guys

Just thought id update this post in case anyone else has the same problem.  I have managed to solve my problem and significantly reduce the turbo lag.

Turns out my turbo is a VNT type so doesnt have a wastegate as such, instead the acuator operates the variable vanes inside the turbo. This was indeed out of calibration.  There is a lock nut and adjustment screw on the acuator arm to adjust the default position.  By process of trial and error, i altered the screw one turn at a time then took the car for a run to see the results. after 3 full turns of the adjustment screw (therfore shortening the actuator arm) the turbo now starts to boost at about 1700rpm instead of over 2000 like it was!

Mick.