blitzed

iTrader: (3)

Hi,
I have a my00 with following mods: full decat,dawes device set at 15psi?,HKS powerflow induction kit,samco hoses and forge recirculating dump valve.

The problem ive got is from cold the car idles fine but when driving its like its running on two cylinders it wont go at all, I have to accelerate really slowly and can hear what sounds like it backfiring through the air filter.
When its warm it lacks power and is very hesitant above 4 thousand revs and even worse when trying to accelerate hard on motorway bout 70mph just seems like running on 3 cylinders again According to boost gauge its normal and no knocklink activity.

Have changed the plugs but this didnt help if anything made it worse, maybe this is because I had the battery disconnected for an hour and reset the ecu?

All help appreciated.
Eddie

TomWRX01

I was getting alot of hesistation/surging above 5k revs although below this car was fine. Took it to garage and found that there was two problems one being a neutural diff switch (which tells the ecu when your in neutral) was faulty telling ecu when driving in other gears that I was also in neutral which then changes ecu to limp home mode with every vibration that sets off switch which gives poor performance and jerky ride. After finding this then car misfired at 5 1/2Krevs onwards which found to be that 2 of my piston rings are failing causing loss of compression at high revs. Look out for your engine turning over very quickly on start up. So you could be losing compression?

TomWRX01

Could also be a coil pack breaking down causing short circuit and misfiring under loaded conditions.

mine subaru 01wrx full exhaust,remap, upgraded turbo, 15psi also

jaytc2003

iTrader: (1)

possibly maf related or lambada sensor
Disconnect maf when the car is idling, if it continues to run, then the chances are that this is goosed. The my99 cars are well known for this, and I am sure it applies to the my00 cars as well.

jaytc2003

iTrader: (1)

also try the standard recir dump valve if you still have it as yours could be leaking under boost conditions

blitzed

iTrader: (3)

cheers guys
will try disconnecting maf tommorrow and been searchin all day for the old dumpvalve , being a my00 it doesnt have coil packs
ed

blitzed

iTrader: (3)

just disconnected MAF, it made the cars idle go up and down erratically to the point of nearly stalling
ed

TomWRX01

When I disconnected my MAF sensor the car stalled straight away and mine turned out to be fine. I would think that any change to idle would mean the ecu is using the sensor which probally means its ok.

jaytc2003

iTrader: (1)

If it stalls straight away with the maf disconnected then that would generally mean that the maf is okay. It is if it continues to run without the maf connected, what that usually means is that the ecu has learnt and adapted to the faulty maf.

blitzed

iTrader: (3)

cheers guys I tried the test again this time with engine warm and car stalled so checked actuator,all pipework regapped plugs 0.61 and still had the problem.
Went down to subarus isleworth and bought new maf sensor for 72 quid and fitted it nows runs the best it has for along time it so responsive .
Ed
wouldnt rely on the maf test too much and i probably will change the maf sensor every other service from now on

DIPSY

What was the car like before dumpvalve and on the my99 2000 induction kit can brake maf sensors .I had three or more mafs on my2000 uk turbo i had and that was with a panelfilter fitted so in the end once month cleaned the metal gauze in the airbox before the maf

Comper100

My legacy has been doing similar things today, i changed the plugs the other day to a slightly colder BKR7E's and now when the car is dead cold - it plays silly buggers missing and backfiring until its warmed up then its fine, it wont even idle properly. Not sure what that is yet but it sounds similar....