V40 1.9D bad mpg

[volvokid]

I usualy average about 54mpg but now im struggling to get it to 43mpg. It shouldnt be due a service just yet, I bought a box of cleaner you put in the fuel from costco last night I hope that does something. What can cause the massive drop?

[kee1173]

I think i remember Fandango having a similar prob with his S60 and i think it was his inter cooler, Correct me if i am wrong Senor?

[The-Les]

it's not just turned into a T4 has it? In my old diesel I was using millers additive that made a bit of a difference, but not 10mpg's worth.

[After_Shock]

Mines averaging about 43-44mpg, just thought it was normal.

[v70torslanda]

Check all the hoses for leaks, tears & splits, check the intercooler for the same. Look for the hoses ballooning under pressure

Listen for air escaping, if the car sounds like it should be painted yellow with Inersoll-Rand stencilled on the side you've got a pressure leak. I'd expect that to be accompanied by some serious black smoke and a drop in performance. DTi Renault engines are also prone to EGR valve failure so I would be having a gander at that too.

Do all the physical checks you can before getting the garage involved, there's not much in the way of electronics to go wrong.

Once you've found the problem and fixed it she's bound to have a coked up cat so that's when I'd be using the Millers and going for a long drive in 3rd & 4th gear.

[volvokid]

Check all the hoses for leaks, tears & splits, check the intercooler for the same. Look for the hoses ballooning under pressure

Listen for air escaping, if the car sounds like it should be painted yellow with Inersoll-Rand stencilled on the side you've got a pressure leak. I'd expect that to be accompanied by some serious black smoke and a drop in performance. DTi Renault engines are also prone to EGR valve failure so I would be having a gander at that too.

Do all the physical checks you can before getting the garage involved, there's not much in the way of electronics to go wrong.

Once you've found the problem and fixed it she's bound to have a coked up cat so that's when I'd be using the Millers and going for a long drive in 3rd & 4th gear.

I will have a look at this. There is no drop in performance; it does smoke at times but no more than any other diesel. I did a 45 mile drive into Aberdeen yesterday and everyone was sitting at 50 so I had plenty of overtaking to do and I averaged 36mpg I’ve never had it that low before even when I’ve drove fast. I reset the clock on the way home and drove at a snails pace and got 49mg.

[CONDYBOY]

Probs just a dirty fuel filter. cheap and easy to replace. I just done mine and back into the 50mpg range now. cheap supermarket fuel really isn't worth it!