A prob with the Foz (2001 S/TB)

[suubyduuby]

Well, volunteered to give a friend a bit of help with his Foz which he has been having some problems with.

It's an 01 S/Tb which he has had from about 30,000kms and now has done about 70,000kms. He was explaining to me that it suffers poor acceleration, kind of feel like it's holding back now and then, and that the CEL goes on and off intermittently.

Went round and took it for a drive and did feel a wee bit sluggish, gave it a rev and seems to have some sort of A/F issue as the exhaust smoke looks a wee bit dark.The car is mint, never been thrashed so its not a blown turbo or anything. Was having a bit of trouble with my OBD scan tool, so did the manual method with the black plugs.

The fault codes I got out of it were 22 (Knock Sensor) and 32 (Oxygen Sensor). Looking at the engine bay, the ignition arranagement is a bit different to the EJ208 in that it doesn't have direct-fire ignition with coilpacks but rather has a distributor setup like earlier WRXs.

Am going to go around and reset his ECU and get him to drive it for a week and see what happens. But in the meantime, any ideas? Is this typical of a failing O2 sensor?

[nt_a_foz]

If its showing 32 and 22 then yeah itl be those failing moret han likely id think wouldnt it>???

Id be replaccing the 02 sensor at least then see if it still throws knock

[Guest itsgotgo]

Had my 98stb checked as it threw a code about a month ago.

The local mechanic said it brought up the O2 sensor code.however on changing it,I noticed the idle was better and pulled a lot better.

Would be worth checking the state of the plugs aswell,mine were toast after that.

Was using copper plugs not iridiums.

Doesnt the knock sensor throw the car into limp mode?

[nztintin]

i ran my foz with a fucked o2 sensor for about 2 years, still ran fine, i only replaced cause i could and got sick of the bright red CEL light showing up early morning!

[suubyduuby]

Yeah I would imagine the knock sensor would throw it into limp-home mode.

I'm guessing the knock code is due to a previously stored code in the ECU - would be interesting to see if it comes back when the ECU is reset..

Is the O2 sensor difficult to get at on the foz? I know on the Leggy its relatively easy to get to, on the LH exhaust manifold...there's a hole in the cover. How much for the O2 sensor itself?

[Guest itsgotgo]

 nztintin']

i ran my foz with a ****ed o2 sensor for about 2 years, still ran fine, i only replaced cause i could and got sick of the bright red CEL light showing up early morning!

yeah tintin your foz is a mystery,mine was just junk with it busted

[quote name='suubyduuby said:

Yeah I would imagine the knock sensor would throw it into limp-home mode.

I'm guessing the knock code is due to a previously stored code in the ECU - would be interesting to see if it comes back when the ECU is reset..

Is the O2 sensor difficult to get at on the foz? I know on the Leggy its relatively easy to get to, on the LH exhaust manifold...there's a hole in the cover. How much for the O2 sensor itself?

not hard to get at,its on the drivers side at the top of the exhaust just at the back of the wastegate.

Just be sure you have the sized tool for the job and try not to loose any bark off your knuckles