R32 Gtr Mixtures

[itbmils]

Guys

do these mixtures look OK

I have an R32 GTR and since having this power run done I have removed the mesh from my AFMs and installed a cold air intake. Now the car seems to run VERY rich (obvious ?)

I sometimes get less than 300ks from a full tank of fuel with a mixture of normal and heavy driving, and I get clouds of blueish smoke under heavy acceleration

smoke is mainly when I accelerate hard (big cloud of smoke) but once I'm on the peddle the smoke stops.

Engine has done about 12klms since rebuild and is running Apexi PFC

So – is it time for a re-tune, or should I try taking some fuel out myself (watching for knock)

[Amaru]

It actually has a pretty decent tune on it AFR wise, its certainly not way too rich (it doesnt even hit 11.5:1).

Your description of blueish smoke isnt petrol, its burning oil somewhere. If it was running too rich it would be a grey/black colour.

[itbmils]

It actually has a pretty decent tune on it AFR wise, its certainly not way too rich (it doesnt even hit 11.5:1).

Your description of blueish smoke isnt petrol, its burning oil somewhere. If it was running too rich it would be a grey/black colour.

interesting - I don't use ANY oil - but it does seem to use LOTS of fuel

I'm also now getting a mild back fire (pop) between gears at moderate load - another sign of too much fuel I thought (I'm not expert tho)

Would an oil leak on one of the turbos cause this ?

NB head was also completly rebuild 12k ago - all new seals etc - so I don't think my problem is there either

I suppose - what I'm aksing is would removing the mesh from my AFMs impact mixtures ???

Edited July 22, 2006 by itbmils

[Adriano]

SHouldn't affect mixtures much, although running a bit lean up top, boost curve not too happy, could be a(or both) O2 sensors, they will make it run rich all the time except under load, resulting in heavy fuel consumtion, what management?

[itbmils]

SHouldn't affect mixtures much, although running a bit lean up top, boost curve not too happy, could be a(or both) O2 sensors, they will make it run rich all the time except under load, resulting in heavy fuel consumtion, what management?

Managementy is Apexi PFC - how would I check O2 sensors - where are they ?

[Guest Mashrock]

that aint rich..

this is rich

[Simonster]

that aint rich..

this is rich

Yes........yes it is

[FATGTS-R]

The graph you posted is a wide open throttle, full load run (the mixtures are not rich at all) and has nothing to do with your economy issue.

Its the mixtures when cruising around that are in question which you dont have a graph of. What was consumption before you took the mesh out?

Its obviously a recently rebuilt engine, so what Ks were on it when it was last tuned?

[itbmils]

The graph you posted is a wide open throttle, full load run (the mixtures are not rich at all) and has nothing to do with your economy issue.

Its the mixtures when cruising around that are in question which you dont have a graph of. What was consumption before you took the mesh out?

Its obviously a recently rebuilt engine, so what Ks were on it when it was last tuned?

good point - I obviously do not have a run showing mixtures at cruising speeds.

I can't say I noticed an issue with smoke or fuel consumption before de-meshing, or even immediately afterwards. But I do have a problem now !!

At this point I'm simply searching for some root cause, and that is the main thing I have changed since the tune. I've also added spiltfire coil packs - and that's about it I think

It's been about 10,000K since it was on a dyno for a full tune – is that too long ?

talk to me about the 02 sensors – where are they – are they easy to replace – how much do they cost and where can I get 'em