Higher engine load than normal when crusing WRX STi Version 8

Hey guys,

Got a weird one, started some time ago..

When doing 100-110kph she hovers around -1psi to 1psi boost. it used to sit around -8 to -6.

Im sure this is the reason why shes worse on fuel. Ive changed spark plugs, cleaned the air filter and AFM.

It is defiantly not just reading incorrect because I can hear the turbo spooling to.

Any ideas anyone? or know of a way I can check for error codes?

thanks

Take the handbrake off.

Normally sits at -20. Whats it sit on at idle? Definitely effect economy.

nah was never that low, has an electronic boost controller in it, so wastegate is definitely closed. I haven't noticed heaps of brake dust on one wheel or anything like that.

Hand brake still works and I've put a few thousand k's on it like this so I don't think its that.

What does vac read in?

PSI, idle is -15 to -16 when warm

 boon said:

Tell the big girls to get out of the back seat?

Also...

Knock knock?

Who's there?

A F.F.S. motor doing weird ****!

Come on boon, not helpful lol

 boon said:

Sorry, haven't had my coffee yet.

But seriously, put the car on axle stands or a hoist and see if one of the wheels is hard to turn.

Turbos are pretty dumb things, the only real way (short of anti-lag) to get them to make more boost at a given rpm is to increase the load on the engine.

Yeah exactly, so there's more load on the motor. I'm trying to figure out why

Unless i get the whole car off the ground, wont they be hard to turn anyway?

Could there be anything wrong with the motor you reckon?

Come to think of it, my front rotors are a bit warped (little shakky under braking) reckon that could do it?

So you dont think so? mine sits just off boost normally, not talking about a huge difference.

Though if shes cold it needed 2psi just to hold 100kph the other day

Something rather hinky. Should idle -20ish. You running a cat?

Nah, should add its got a vf30 not vf37.

exhaust is pretty much straight through 3", one resonator, one flexi, one muffler (prodrive one)

Leaking fuel injector maybe. I had a lower injector seal blow out on the motorway and boost wouldnt go under 5psi the rest of the way home

You'll have top feed injectors though so one would have to be stuck open by some debris...

Did you fix that leaky nipple from hampton? Fully dont remember

 boon said:

Tell the big girls to get out of the back seat?

Also...

Knock knock?

Who's there?

A F.F.S. motor doing weird ****!

****ing cheeky **** hahahahaha

 chulozumo']Did you fix that leaky nipple from hampton? Fully dont remember

****ing cheeky **** hahahahaha

Yeah i did, that was just a the brake caliper - and was doing it before this

[quote name='Optical said:

possible, would have to the most minute leak though wouldnt it?

checked the tire pressures and wheel alignment ?

is it running on all 4 ?

do you rekon your foot is harder on the gas pedal ? or the engine is doing it on its own

 lachlan said:

checked the tire pressures and wheel alignment ?

is it running on all 4 ?

do you rekon your foot is harder on the gas pedal ? or the engine is doing it on its own

Yeah it feels ok other than that, power feels good, foot doesn't seem any harder, but it could be, would be such a small mount extra i would think.

Is the guage playing silly buggers ?

Does it still boost to the same number as before..

 pedro said:

Is the guage playing silly buggers ?

Does it still boost to the same number as before..

I dont think so, both the manual gauge and the electronic controller read the same.

i can hear the turbo so i think its reading correct, seems to have same max boost

Has it been tuned? Maybe the timing is advanced heaps to get the boost on quick?

 loner said:

Has it been tuned? Maybe the timing is advanced heaps to get the boost on quick?

Wont be that.

Think hes running it on diesel so no vac.