Hesitation/judder between 2200-2700 rpm

[-bobda-]

It's definitely not juddering any more, the hesitation is slight but I can live with it until I get back from holiday in 3 1/2 weeks.

I might even see if I can borrow a boost guage and adjust it properly.

Originally Posted by peteS40

Do you think the fault might be to do with the turbo going from overboost to low boost repeatedly, causing a judder feel? Does it feel like that do you think? Possibly when they fitted the turbo they did not set the wastegate link correctly... seems weird that the problem has occurred since then (so it is not the same problems as before, but has come since all the big work?) So I was trying to think if they messed it up somehow.

Pete

Your comments are interesting Pete because I have a '98 2.0T auto at 98K that does exactly what you are describing – begins to judder and looses power momentarily at motorway speeds or during heavy acceleration and then sorts itself out after while. Sometimes it also does it when stationary in a queue at a junction. If I put it into neutral the juddering stops.

Because it doesn't happen all the time, for example within 10 miles of a Volvo service centre, it is difficult to explain to a mechanic

Further, I recently had the engine turbo return pipe seal and gasket changed, perhaps this might be why?

Originally Posted by Abradders

Further, I recently had the engine turbo return pipe seal and gasket changed, perhaps this might be why?

Probably not, but why did you have those changed? Was oil leaking round the o-ring gasket on the engine end of the pipe?

Pete

Yes that was exactly the reason for the replacement.

Have just driven home on A roads so no more than 50mph or so. Pulled up to drop my passenger off and then when I pulled away the car starting juddering again. Hasn't done it for about sevene days or so.

It didn't do it until I had theabove done and alsoEngine RPM sensor changed Fault code EFI 131 and the throttle housing cleaned. I have also had intermittant DSA fault light problems but it goes out after ten minutes of driving or so.

Very annoying

I found fitting that return pipe to be a bit of a pain in the bum coz it has to go straight in on the engine side and so if fitting to a turbo already on the car I think it would be easier to loosen the nuts holding the turbo to the exhaust manifold to give a bit of movement to get it on the turbo.

So it is possible (although unlikely!) that they failed to tighten these again or the nuts have loosened (replacement nuts I decided to get, and they were locknuts from volvo). For sure if this was the case you'd get both lots of vibration and loss of power if the seal went. As I say, a bit unlikely though... but simple to check all is done up by removing heatshield and checking.

What's more likely - if it is all connected - is it is related to changing those other things you had done. Did you have them all done at the same time? If not, do you think the problem is more related to one thing than another?

Dunno about DSA... best thing have the fault code read I would say. It must be logged. To be honest, I'm not even sure how the DSA works on these cars. My guess is it uses the ABS sensors and also the brake pedal switch to determine if you are braking or not, on my previous car the traction control was affected by the MAF sensor as well.

Pete