Bertiebassett

Hi I'm hoping some one can help. I've got a impreza 99 uk 2000 the car is holing back in boost and it have the fuilt code 22 witch if im rite it's the knock sensor would this cause this holding back on the boost? I've changed the spark plugs checked the ht leads look quite new I did get a shock of the coil pack after doing the spark plugs stupidly of me put my hand on the coil pack when running the car not sure if this should of happend or the coil pack is faulty? And could this cause it to hold back on boost? And could the coil pack cause the knock sensor fault? If anyone could help would be great

Thanks rob

1509joe

iTrader: (2)

Pretty sure code 22 cuts the boost but a faulty coil pack could possibly create a misfire if the spark is jumping thus sending the ecu a signal it's not expecting an then it MIGHT throw code 22.

Bertiebassett

Code 22 come up as the knock sensor so the knock sensor can cut the boost?

6VOLT

iTrader: (1)

If the knock sensor is working properly it will be detecting detonation or any ohter loud mechanical noise and thus retarding the timing higher up the rev range.. Ie when on boost.
If it is faulty then it will be thinking it is sensing the above and thus doing the same.
Swap it out for a known working unit and reset the ecu. Ie. Disconnect the battery for a bit.
If it stops then your good to go.. If it persists then you want the engine looking at.

Bertiebassett

The car runs very smooth and sounds perfect ill do what you say what I understand the knock sensor is a pig to get to? And there's no chance a faulty coil pack could be setting it off? Thanks for the advice very helpful cheers

6VOLT

iTrader: (1)

The knock sensor is essentially just a listening device. If the car runs smoothly then I doubt you have a faulty coil pack... Otherwise it wouldn't run smoothly . The knock sensor is located at the back of the block under the intercooler. Not too bad to get to.
When under the bonnet just up the revs at a steady pace to around 2.5 k and have a listen. You may notice a noise that you don't usually hear in the cabin... Not trying to put the ***** up you, but it's good to be methodical with these things.... If there is an. Audible noise that you can hear then there is no need to go digging.
Cheers
Dan

MattyB1983

iTrader: (51)

Knock sensor is a 5 min job to change. Very easy job.

Bertiebassett

Thanks guys ill do that and report back

Bertiebassett

I've done what you said to do sounds fine no tapping or knocking but it does sound like a misfire tho?

6VOLT

iTrader: (1)

Pull the coil pack then mate, get one on that is known to work. Reset the ecu and have a stab

Bertiebassett

Hi I know it's been a while but still having the same problem I've changed knock sensor now all faults are all cleared and I've also changed the spark plugs again coil pack boost solenoid even tried another ecu but no luck still holding back under boost any idea where else to start looking?

MattyB1983

iTrader: (51)

MAF.

Bertiebassett

Would that not put the cel on? Or a fault code?

LuckyWelshchap

Insult to the intelligence, and in my view taking the mickey out of the decent, genuine posters who have provided support by offering advice.

Any relation to AndyJoneswrx?

Bertiebassett

What? No I'm not related to him why do you ask?

MattyB1983

iTrader: (51)

You'd think so but I've seen instances before with faulty MAF's and no cel.
The MAF'S are notorious for failing, start by taking it off and cleaning it and see what happens.

Bertiebassett

Ok mate cheers ill give that a go