Low Millage xc70

[Keithp]

Not been on here for quite some time, I have just picked up a 38k 07 xc 70 in immaculate condition body and interior .

But since picking it up on sat I have done about 375miles in it and noticed that it is quite rough between 1500 and 2000 rpm, are these engines prone to being rough in this are or have I bought a lemon !

Sitting at 70 its smooth cant fault it , and it goes when I prod the throttle , put it this way my commute is a 120 mile round trip and I am taking a well uses / abused focus which had over 130k on it in preference to the volvo in the morning.

Any pointers or input welcomed !

Keith

[oragex]

Congrats. Diesel engine?

[Keithp]

Yes , missed the important bit , Diesel , 185bhp.

[Georgeandkira]

Also, is it auto or manual. While you're at it, add a sentence or two of description.

Get a good quality fuel system cleaner (one with PEA), fill the tank to 3/4 full and take it out for a spirited run.

If it's an automatic simply do a drain & fill. We all know color constitutes no scientific analysis but if the fluid is dark or seems somehow contaminated you can take appropriate action.

Remove both rear rotors and inspect the condition of the parking brake linings.

Any service records? Coolant, brake fluid, and engine oil may be in need of refreshment.

Engine and cabin air filters?

Timing belt may be due because of age.

If your engine has that exhaust handling pipe which fills with black gunk, inspect/clean it.

Congrats on finding such a young 12 year old car.

[CaptainSlow337]

I'd be checking the engine mounts personally.

[Keithp]

Car is an auto, bought from a dealer, looking over the car it appears to be looked after, tires are all relatively new and quality brand, stamps in book are main dealer up to the last three which are from the same indi. The dealer I bought it from did a oil and filer change before I picked it up.

Engine bay is clean , but not looking like its been steamed cleaned , spare is unused battery looks recent. interior is pretty much mint no visible wear and tear anywhere.

I am planning to do the belt as a matter of course in the absence of any invoice saying it's been done.

At motorway speeds it is smooth and goes well, its just when you are around the 1700 - 2000 mark in any gear its rough clears once past the 2k mark revs feely and box changes gear fine no slurred changes.

I am told the engine is not know as a refined lump but, at the RPM area there is a resonance through the steering wheel and the accelerator.

[oragex]

That is interesting. I don't believe this to be a normal behavior, on the other side it may be hard to pinpoint so the kind of issue to find with some patience testing part by part without replacing them. We like to use parts from a few select brands, Lemforder, Sachs, Continental, Aisin, Ina, Bosch (for the timing belt, and while there I believe we don't touch the water pump until 200K miles on these cars), Hutchinson for engine mounts (these fail on the D5 engine as they are vacuum type). We also use specific fluids, I prefer coolant from Volvo (mixed with distilled water), Pentosin for power steering fluid, Dot4 synthetic for european cars for brakes, Toyota Type 4 3309 or genuine for transmission fluid

[cheshired5]

Boost should come in around 1500rpm but if the turbo vanes aren't in the correct position for low engine speed boost, you'll get a flat spot then normal boost as engine speed increases.
If that is your problem, the turbo vanes could be sticking or the servo motor which controls the vane position is defective in some way.

The vacuum engine mounts won't be a factor in boost issues because boost is servo motor controlled on Euro 4 185 D5 as opposed to being vacuum controlled on a Euro 3 D5.
Leaking vacuum mounts can and do cause boost issues on Euro 3.