ultraviolate

Ive just fitted a K&N cone filter to my 97 impreza but ive now noticed a clicking noise when i rev the car gently. It seems to be coming from a small valve maybe or pressure sensor just above the filter to the left of the engine bay. Any help would be much appreciated cos I dont want to take the filter off.

greasemonkey

If in any doubt, take the filter off and return the induction mechanism to standard!

Can you take a picture of the valve/sensor concerned and post it up? It's difficult to comment without knowing exactly what you're talking about.

Scratch

iTrader: (1)

Sounds like the boost solenoid clicking.

I can hear mine do it (my98) when the engine is quiet enough.

ultraviolate

Sorry cant post a photo cos I havent got a digital camera. Surely the boost solonoid isnt supposed to chatter like that. I think I will put the original filter back on as I dont want to risk any damage to anything. Does anyone want to buy a slightly used K&N induction kit Ha Ha.

chrismc

Mine clicks too, think you'll find it still does even if you revert back to the air box. You'll lose out on performance though and mine actually made my car more economic as well as faster and more responsive.

I did read somewhere however that oiled filters aren't good for the MAF. Not had any problems myself and have been using filter for about 18 months.


Chris

greasemonkey

This is NOT the good news you think it is Chris.

Everything you've said suggests that the addition of the cone filter has caused the MAF sensor to under-read, thus causing the ECU to inject a reduced amount of fuel into the cylinders. The weaker mixture will (paradoxically) make the car feel quicker, and improve fuel economy, but the downside is that you can also get cylinder heating and detonation.

If you have a KnockLink (and ideally an AFR meter) fitted and it tells you everything is okay, that's cool. If you don't however, I would be very cautious about this setup. For all you know it could be detting its heads off, and that could lead to a very expensive engine repair.

chrismc

Thanks for the advice!

What would the long term effects be and symptoms? Reason I ask is that I'm having problems at boost levels greater than about 0.6 bar. Not the suddon loss of power associated with the solenoid problem but more of a hesitancy. Thought it was an air leak but maybe not on this info? Ecu does give me the solenoid code though?

Is this just a problem with the oiled filters? Would the steel mesh ones be OK?


Further advice woould be much appreciated!

greasemonkey

Depending on how bad it is, long term effect is a blown (or seriously damaged) engine!

[quote] Reason I ask is that I'm having problems at boost levels greater than about 0.6 bar. Not the suddon loss of power associated with the solenoid problem but more of a hesitancy. [quote]
Could be any number of things, from det to an oil contaminated boost solenoid. You need to find out more - a KnockLink would be an invaluable diagnostic tool.

Could be worth cleaning it.

This particular issue is nothing to do with whether the filter is oiled or not. Changing from the standard induction tract to a cone filter can change the way the air flows past the airflow meter, thus creating a permanent misread, while if the fitting of the induction kit allows the MAF tube to vibrate, another damage mechanism can be introduced.

The steel mesh filters just don't filter effectively enough, and, as mentioned above, there's a potential issue with any cone-type filter, unless the ECU is remapped to cope with any change in the airflow metering. The safest/best solution is going back to the standard induction tract with a good quality panel filter like the STi, K&N or Green products.

chrismc

Think I'd better get myself a knocklink! Any suggestions where?
Where in Buckinghamshire could I get a remap and what sort of cost am I looking at?

greasemonkey

http://www.brdevelopments.com would be a good answer to both questions.

chrismc

thanks

scooby L

Mine had hesidancy like you described m8.
When the car was re-mapped they told me it was because of DET, and the ecu trying to protect the engine by backing off the timing, thus this conflict of power/safety in the ecu caused this wierd feeling under hard acceleration.
Get it checked out.. better safe than sorry..

ultraviolate

I sorted my particular problem out. The cone filter was touching the boost control solonoid and magnifying the sound it was making.(inside the car it was almost unbearable!) however even though the car sounded like it had a dump valve fitted when I changed gear it was considerably slower than with the standard filter so Ive taken it off. Does anyone Know if a K&N panel filter would be beneficial. By the way the technician at my local subaru dealer says fitting an induction kit is a very bad idea as all sorts of nasty things can happen

ultraviolate

Hey mate

Yes im interested in selling the induction kit but on the advice of my subaru dealer i arnt going to fit another so i arnt realy interested in a swap. thanks anyway. whats your offer.

VXTPete

Filtration on steel mesh filters varies greatly. Some are very very poor, others are far from it