99 V70XC engine rpm fluctuation.

PatternFlyer · Post by **PatternFlyer** » 07 Sep 2015, 13:06

ok... 158k miles on it.
currently driving as front wheel drive (front u-joint on the drive shaft need to be replaced).
has oil leaking some where under the top engine mount close to PCV or Turbo.

started having symptom similar to what people describe as ETM/MAF sensor failure.
rpm goes up & down around 2 to 300rpm while running or idling.

no code

Cleaned MAP and ETM with no difference.

What should I check?

Post by **RussB** » 07 Sep 2015, 17:50

ALL vacuum and turbo lines and hoses. You need to be sure nothing is leaking. With that much time on the car, replacing them all isn't such a bad idea.

What color sticker does your ETM have? Has it ever been replaced before?

PatternFlyer · Post by **PatternFlyer** » 08 Sep 2015, 23:41

RussB,

ETM has yellow sticker.
It has not been replaced since I purchased the wagon with 98K.

Sommerfeldt · Post by **Sommerfeldt** » 09 Sep 2015, 02:46

RussB wrote:ALL vacuum and turbo lines and hoses. You need to be sure nothing is leaking. With that much time on the car, replacing them all isn't such a bad idea.

This. Seems to me that 80% of issues with these cars are vacuum/boost/air leaks. At least when the car is running and rolling. Luckily, it's also the easiest pieces to swap out.
I've had 3 used 850s and one S70, and the first thing I did when I got them home, was switch out all the vacuum and intercooler hoses. (except one on the current one... which promptly gave me trouble.

)

- S

PatternFlyer · Post by **PatternFlyer** » 10 Sep 2015, 01:34

I am going to order silicone hose from IPD.

Are all the vacuum hoses same size?
IPD shows TCV hose kit which appears to be same 5mm ID.
I will probably do the complete PCV again just in case.