Running Lean - stumped as to why

[JustCallMeOrlando]

It's the loom. I know it, you know it. Either get another loom, or put the Microtech on it and make the problem go away...

[VikingDrift]

not sure if this is helpful mate, has your car got a fuel pressure reg on it at all?? my mate had a leaning out problem in his FC rx7, and he was confused cos high fuel pressue etc, turned out the rising rate pressure reg was plumbed in backwards lol which aparently restricts flow. Also in the same vein you said it had good pressure but have you checked the flow rate at the rail? Don't ak me how tho eh haha

[CrUZida]

As stated in the first post, flow has been checked.

Orlando, if I use the microtech I'd want to use the existing loom, as its already wired to the ABS sensor, the PPS sensor, the heater temp, etc etc. And if the problem is with the loom, chances are it would remain with the microtech.

[JustCallMeOrlando]

Buy another UZ loom

[CrUZida]

Spent too many hours on this one already

[oldcorollas]

well if it's not fuel... then it has to be air.... or ignition timing

[CrUZida]

Can't be air, worked fine with other ecu.

Put the o2 sensor back on to passengers side, read ~14.1:1 on start up, pretty much stayed there all the way until warm. So problem def still remains with drivers side.

Unplugged the loom at the ecu/fusebox/glovebox and checked a dozen or so wires, everything came up trumps.


So its going to be booked in to an EFI place this week hopefully, see if they can sort it out.

[CrUZida]

Car is at EFI place at the moment.
They called me this morning to say that the drivers side o2 sensor reacts really slowly, so they are changing both those out for new ones.

I expressed my opinion that I didn't believe they would be the cause, but then he said that they can't properly fault find unless they fix everything they find faulty on the way, which is fair enough.

I actually expected them to have found the problem by now, wishful thinking maybe

[CrUZida]

Speak of the devils, they just called, and with new o2 sensors they reckon everything is fine...

So on the weekend I'll install the wbo2 again on the drivers side, and see how that goes...

[RONA]

Results?¿¿

[CrUZida]

I was too busy working on the Soarer over the weekend to put the wbo2 back into the supra to see the results.

Car seems to drive better, but I haven't really driven it since replacing everything, so I don't know if its the result of the o2 sensor or the new fuel pump, clean injectors, ecu caps replaced, etc.

I'll try do it this weekend.

[CrUZida]

Put the wbo2 into the car today, and well, the problem is fixed.
Car sits between 14.7-14.9:1 at any speed and at anything below 30% throttle.

So I have no idea why the o2 sensor was causing this issue, but hey, it did.

Never underestimate the power of the o2 sensor!

[RA35GT]

Wow, thats some weird sh1t.

Maybe there is a long term fuel correction that is active in open and closed loop?

[abently]

That's ridiculous, a dying o2 sensor wanting to take the motor along with it.. lol.

Well done on finally sorting it though. Big relief I expect.

[CrUZida]

The wierdest things were.

a) it happened straight after an ecu reset (which is why I didn't think it was an o2 sensor issue)
and
b) when it was running lean on the freeway it would start at 18:1 after an ecu reset, and end up at 16:1 after 10km of cruising, so to me that says the o2 sensor is working correctly.

Either way, its all sorted.