Running Lean - stumped as to why

[madmont]

What is the AFR at idle?

[brett_celicacoupe]

coolant temperature sensor?

what factors does the ecu use to determine enrichments/enleanments?

air temp, water temp...?

[brett_celicacoupe]

i just bought a UCF11 so i could check my mixtures while cruising if you want.

i got the techedge 2j1 wb02

[oldcorollas]

low water temp = more rich
low air temp = more rich.

high air temp = leaner but... isn't air temp sensor in the AFM?

[abently]

Things for the weekend.

• Try spare Celsior ecu (suspected UCF10 ECU (no TRAC), had much less wires)
• Try working Celsior AFM
• Install wbo2 into Celsior and see what a good setup should do.

No worries. Let us know how you go. I hope you figure it out cause you'll be wishing you never bothered trying if you never ever find the issue.

[CrUZida]

AFR at idle (from memory) is not much different to cruise, around 16:1

Coolant temp sensor was my first thought (when it was running on the Delco), so I bought a new one. Made no difference (I realise this isn't a good comparison, but...)
But the Toyota coolant temp sensor installed on this motor is the one out of my Soarer motor, which easily read within 5degC of the coolant temp. So its unlikely the problem.

Air temp sensor is in the AFM, and is not a replacement sensor (AFAIK).

[YLD-16L]

AFR at idle (from memory) is not much different to cruise, around 16:1

Wierd, is it hunting at that AFR at idle?

[CrUZida]

No hunting, smooth idle.

[YLD-16L]

No hunting, smooth idle.

Interesting that it is around 16:1 and smooth idle, anything I've played with around that AFR at idle will start hunting.

[CrUZida]

Major update time.

I just had a new exhaust put on the car. Previously the wbo2 sensing point was just after the Y-pipe. Now its just before the Y-pipe and only measuring the drivers side.
Drove it home and noticed that it was leaner than before (like 18:1 on cruise) and as you accelerate it went from 14:1 to 17:1 ...

So today I decided to pop the wbo2 in the passengers side (factory spot) and low and behold, muchos richos. Mid 11's under accel, mid 13's under cruise, never saw it above 14.5:1 unless slowing down (even mid 13's at idle). Pretty much where it should be with that much fuel pressure. (actually saw it in the low 10's for a bit)

So, thoughts?
I'm thinking one injector may not be working, or similar. Something is making it pump a shitload of fresh air.

[oldcorollas]

swap injectors from driver to passenger side, one by one, until it goes from lean to rich...?

[Officer Doofy]

surely pulling the plugs from the suspect side will give an idea

Great to see you stuck at it and are starting to get somewhere!

[oldcorollas]

does reading plugs still work for unleaded fuels? apart from black = well rich, not black - not rich?

[thechuckster]

how are injectors wired up? two banks or something else?

[CrUZida]

4 batches of 2.

Will start with making sure all injectors are ticking, then move on to checking compression (incase one inlet valve isn't closing)