Helo guys.

My car is an Impreza 2.0 Turbo from year 2000.
Mods are Viper airfilter kit
Revotec BOV

After i changed this the car seems to be hesitating in every gear uptil about 4000 rpm's. after that it goes ok again. Also in the 5th gear the car does not pull at all!!

I tried to reset the ecu yeasterday by letting the car stay over night without power, but it didn't help.

I must also mention that i had to change a small copper (or something like that) ring that was leading the oil that is cooling the turbo, because it was leaking. Then they refitted everything and it seems very slow in all gears. I thought it might could be some hose that was loose or anything, but I couldn't see anything that was loose.

What can be the cause of this? Any help would be apreciated!

Thanks, Thomas

 

I went to a garage to make a diagnostic of my engine. there they found out that my AF sensor was reading 1.4 instead of 1.2 which is normal. don't know the currency of those numbers. but anyway after changing the AF sensor to a nwe one, the car worked perfect again. they measured the new AF sensor with the 1.2 and everything is working again. my question still remains tho if it was the new open air filter or the BOV that made my AF sensor break. What do you think?

 

It would surprise me that the intake or even the blow off valve would burn out your air fuel sensor (which is really an O2 sensor). If I had to pick either, I would say that it was the Blow Off Valve. The intake makes power by leaning the Air Fuel out just a little bit, while the blow off valve can sometime create a very rich condition when you shift. When you hear that cool woosh sound, thats air being let out of the motor, but the computer tends to keep throwing fuel in the motor. That rich condition may contribute to a significant amount of carbon build up, and render the sensor bad. Also, not running catalytic converters does this.

 

5 years of hard driving can hurt an O2 sensor. Then, you put on that BOV which makes things all rich and it prolly did the O2 sensor in. If their diagnostics were honest, and the fixed worked, I'd bet the guys at the garage were right.