V70: Engine No acceleration

[5062mike]

Hi. Am new to this forum so hope I get it right! Have a 2009 V70 diesel which has done 156K, well maintained and used to run perfectly. Now have a problem and hope someone can help. In the morning when the engine is cold it runs perfectly and acceleration is normal. After about 5-6 miles when the engine has warmed up it still runs smoothly but there is almost no acceleration. Foot to the floor produces almost nothing. Somebody has mentioned a possible fault with one of the two sensors - but I don't know if that is correct or even where they are. Many thanks.

[Simmy]

you will need to get the codes read with a good diagnostic scanner before attempting any kind of repair it sounds like you are experiencing a limp mode situation good diagnostics can save you from spending money on parts you don't need.

[Sotosound]

Originally Posted by 5062mike

Hi. Am new to this forum so hope I get it right! Have a 2009 V70 diesel which has done 156K, well maintained and used to run perfectly. Now have a problem and hope someone can help. In the morning when the engine is cold it runs perfectly and acceleration is normal. After about 5-6 miles when the engine has warmed up it still runs smoothly but there is almost no acceleration. Foot to the floor produces almost nothing. Somebody has mentioned a possible fault with one of the two sensors - but I don't know if that is correct or even where they are. Many thanks.

Which diesel is your car? 1.6 drivE, 2.0d, 2.4d, or D5?

Also, is it manual or automatic?

[5062mike]

The car is a 2.0 diesel manual. Thanks for the advice - will find an auto electrician with diagnostic gear before trying anything.

[Kev0607]

Originally Posted by 5062mike

Hi. Am new to this forum so hope I get it right! Have a 2009 V70 diesel which has done 156K, well maintained and used to run perfectly. Now have a problem and hope someone can help. In the morning when the engine is cold it runs perfectly and acceleration is normal. After about 5-6 miles when the engine has warmed up it still runs smoothly but there is almost no acceleration. Foot to the floor produces almost nothing. Somebody has mentioned a possible fault with one of the two sensors - but I don't know if that is correct or even where they are. Many thanks.

My guesses (and that's all they are without diagnostics) would be a dirty EGR valve, MAF sensor, MAP sensor, DPF issue, boost leak (split pipes) or a clogged fuel filter.

Could be so many things. You're best getting it looked at by a professional.

[Sotosound]

Originally Posted by Kev0607

My guesses (and that's all they are without diagnostics) would be a dirty EGR valve, MAF sensor, MAP sensor, DPF issue, boost leak (split pipes) or a clogged fuel filter.

Could be so many things. You're best getting it looked at by a professional.

A dodgy MAF sensor on my similarly engined 2009 Mondeo 2.0 TDCi occasionally caused it to hesitate and run rough under full acceleration and then go into limp mode.

Switching off and then restarting the engine would clear the fault, but only until the next occurrence.

I cleaned the sensor a couple of times but only a replacement sensor properly fixed it.

Time to live "La VIDA Loco".

[5062mike]

Thanks for all the advice. Will certainly get a tech guy to look at it (when I find one!) but am curious about one thing. Why does the car behave normally when cold but the problems start when warmed up after 10-15 miles. Does that indicate something specific?

[Kev0607]

Originally Posted by 5062mike

Thanks for all the advice. Will certainly get a tech guy to look at it (when I find one!) but am curious about one thing. Why does the car behave normally when cold but the problems start when warmed up after 10-15 miles. Does that indicate something specific?

I'd explain that to the mechanic. Hopefully there's a fault code when he hooks up diagnostics, which will point him in the right direction.

I suspect an you have a clogged EGR valve. I've had it in the past with other vehicles where they start fine, but when the engine warms up and you put your foot down, there's no power. Turn the engine off, start it again, and off you go for another few miles. That's not a permanent solution obviously, but it may help if you need to get home.

Get a mechanic to look at it and see what he says. Just make sure you tell him the problems you're experiencing. If you tell him nothing, he's not going to know. Ideally, you need a Volvo specialist.