running lean

[Pappu1]

got an interesting one:

mates v7 sti runs lean with afm plugged in

with no afm runs rich like normal

tried few afm (known good ones and same thing)

runs 13 on afm and 11.2 or less on no afm

no leaks evident (altho all beathers are to atmo for now - blocked off at intake end)

has catback

good sparks and walbro

boost at 9psi for now

what wud cause it to run lean?

[ODB]

Id be checking the new fuel pump for bad connections somewhere.

Probably the most logical place to start.

[Pappu1]

but it fuels really well with no afm (good AF ratios)

i was thinking leaks/cracks in intake but none show up

[Guest]

afm plug clean? good connections?

[Pappu1]

 evowrx said:

afm plug clean? good connections?

tried 2 known good afm 9from running car even lol)

and same issue

[Guest]

not afm, check loom end give it a good clean...

[Pappu1]

hmm will txt him to do that

any other ideas

[Guest]

bent pin in plug maybe. Could be broken wire trace loom make sure it all looks good.

Just logical shit lol.

[Pappu1]

stock ecu

with stock map

then tried a richer afr map - same issue

hmmm afm wiring ay..

will have a check

[Guest]

swap out ecu if that doesnt work could easily be a connection but what else could effect it?

what filter setup?

[Pappu1]

 evowrx said:

swap out ecu if that doesnt work could easily be a connection but what else could effect it?

what filter setup?

hmm bung ecu ay..

ok i will run with that..

will swap ecu and retry

at moment its pod but been tested on another car

but im sourcing a stock box and test with that

[Guest]

have you still got the car kicking round? just do the cranberry.com mod...

[jpar196]

exhaust leak pre turbo or vacuum leak in the turbo inlet will make it go rich,

I know my car was running leaner on the Dyno at E&h, found 1 of the 3 bolts in the header flange at the collector is gone ! lol that would explain the loss in power and farting

[sultan]

 pappu said:

got an interesting one:

mates v7 sti runs lean with afm plugged in

with no afm runs rich like normal

tried few afm (known good ones and same thing)

runs 13 on afm and 11.2 or less on no afm

no leaks evident (altho all beathers are to atmo for now - blocked off at intake end)

has catback

good sparks and walbro

boost at 9psi for now

what wud cause it to run lean?

you call that lean. now this is lean:

[Pappu1]

 jpar196 said:

exhaust leak pre turbo or vacuum leak in the turbo inlet will make it go rich,

I know my car was running leaner on the Dyno at E&h, found 1 of the 3 bolts in the header flange at the collector is gone ! lol that would explain the loss in power and farting

Damm that's good idea

Btw how is car now? U went back to retest?

Sultan that is some hard lean!!

[JWDRPN]

Exaust leak pre turbo how does this work??

[jpar196]

oops did I say rich ? I meant the turbo intake leak and pre turbo leak will cause lean mixtures

[WRXONP]

Sounds like a leak to me and only the AFM is registering the air and more is sucking in the intake resulting in leav mixture (sucking un metered air)

To me - if AFM wiring was bung - it would run same with AFM off as it would on

Or if wiring was dodgey - it would intermittently be changing