Fuel/Air & Boost Readings...

[C. Will Corrado G60 2 0]

HI all,

 

Just had a Boost 30/30(vac) & Air/Fuel gauages fitted and want to know how to read them properly.

 

My Boost gauage reads vac more than boost is that right? Example being 2nd gear stead going along vac around 10/15. Floor it from there and I get around 11psi (press). Does this sound right?

 

The air/fuel gauage is impossible to read as it's bouncing around from lean to rich all the time (sometimes stead).

 

Can anyone help me out here?

[G60Dan 0]

Re boost: do you have a smaller pulley?

[C. Will Corrado G60 2 0]

Yes, I think it's a 68mm plus a stage 4 charger and FMIC.

[G60Dan 0]

Should be hitting about 1 bar/15psi on a 68mm pulley - sound like you have a boost leak, which also might explain the fluctuation in your air/fuel.

 

I have a boost leak at the moment on mine & am only seeing about 11/12 psi - I think I have tracked mine down now, if it ever stops raining I'll be able to sort it out! :roll:

[C. Will Corrado G60 2 0]

Ok, thats what I hope it is!!!!! :|

 

I'll have to start checking, how do you go about doing that?

 

Cheers

[G60Dan 0]

Go around & make sure all hoses are done up nice & tight, & make sure none have holes in them. I don't think there is any fool proof way of doing this. If your 100% sure it's not a leak from a hose, it could be the intercooler is loosing pressure. My money would be on the hoses though.

 

Mine I think is where the hose that comes off of my boost gauge meets the "T" piece @ the inlet manifold, It's a really crap fit & I can move it round which can't be good. I'll be sticking Jubilee clips on everything boost/vacuum related just be sure.

[C. Will Corrado G60 2 0]

Thanks for the info I have a feeling it's where my pipe work is fiited to the FMIC as I've had problem with it popping off in the past.

 

If only this rain would stop. I just fiited my new wiring loom for the front light which I brought before Christmas!!!!! :lol:

 

Cheers

[g60bv 0]

your boost reading, what rpm did you see the 11-12 psi, ?? the air fuel meter will cycle up and down, this does not meen your fueling is out, the ecu (digifant) uses the lamda on a closed loop, so it reads and closes etc, hence the meter going up and down. which of couse means reading it nearly impossibly :cry: the only real answer to make the air fuel meter work is to have a second lamda installed in the exhaust, cheap but a pain in the arse. this way you can accuratly read whats going on. and a must have on any modified engine,, i my self wasted £120 on the luminition 19 l.e.d meter. before working this out :(

[C. Will Corrado G60 2 0]

Well I wish I knew that first, now I just have to drive round with a disco in front of me!!!!!

 

Can't really tell what RPM it was at as I have noted it properly yet but high!

[LowG 0]

When you fully open your throttle you will see a steady reading on the a/f gauge, they are accurate up to a certain rev range but worth the money to prevent any major failures. So try it at wot and see what you get.

[bazgreener 0]

The air fuel gauge will cycle up and down when on part throttle, that`s the ECU adjusting the mixture to try and keep it stoic(ideal air/fuel ratio), it should show a full reading when on full throttle for rich and no reading at all when off throttle over about 1800 rpm, this is the fuel shut off working and full weak reading showing on the gauge. Thats how mine works anyway.

 

 

:)

 

Baz