Running Lean - stumped as to why

[oldcorollas]

Amichie, what voltage should the Vf be?
From memory 0.5V is unchanged, but which way is rich, which is lean ? 0.75 and 1V lean, 0.25 and 0V rich?
Does the car need to be running, or just ON ?

this?.........(oops, maybe not.. anyway.. check with ya sensor)
http://www.vortexbuicks-etc.com/nbsensor.jpg (now as linky)

[CrUZida]

The Delco ECU was mapped for the stock 215cc injectors.

Stu, the Toyota long range enrichment voltage is nothing to do with your o2 sensor voltage.
Its just something the Toyota ecu does so you know if has richened or leaned out the fuel. (ie, if its richened the fuel up, you know you have problems).

[Officer Doofy]

http://mkiv.supras.org.nz/articles/engine_2_25.htm

Having similar issues with my 1jz atm. 1uz might be similer for above?

[oldcorollas]

i realised that after i first posted diagram
i thought i'd leave it anyway....
have you checked the output of the narrowband/s?

you wouldn't happen to have a rooted fuel pressure reg?

[amichie]

Vf works with engine on and /or running at any rpm/throttle position.

2.5V is normal
1.25V is ECU trying to lean out a little.
0V is ECU trying to lean out a lot.
3.75V is ECU trying to richen up a little etc etc.

[CrUZida]

Checked Vf this morning, was 0V.
Did a quick reset of the ECU (maybe not long enough), still 0V. I've left the EFI fuse out overnight to ensure a reset is performed. Will check again tomorrow morning before going to work, and again when I get there.

The is a VF1 and VF2. Presumably one for each bank?
(I've verified that both VF1 and VF2 are continuous to the ecu).

Interestingly when I fired it up this morning I checked the o2 sensors voltage (only 30secs after starting).
One was ~0.8V the other was ~0.3V.
Go figure ?

Another random thing, checked engine timing (TE1 and E1 bridged) and it was ~8deg. Not sure why not 10deg, but never checked another 1UZ. Timing is not adjustable either.

[CrUZida]

you wouldn't happen to have a rooted fuel pressure reg?

When I first started checking things I tested the fuel rails/etc off a spare motor. Exact same results.

[oldcorollas]

Interestingly when I fired it up this morning I checked the o2 sensors voltage (only 30secs after starting).
One was ~0.8V the other was ~0.3V.
Go figure ?

they are heated sensors?
check after 1 minute or so and if they are still different, then either one is borked, or you got weird fueling?

[CrUZida]

Nah, unheated, which is why I'm basically ignoring the reading. I just thought it was strange that they read so different.

[oldcorollas]

it is a bit strange they should both read low until heated (iirc) so for it to read high means it is heating up fast/faster?

[stevevp]

its a long shot but can you check your ignition timing again ? both at idle and then at around 2000 rpm. if it retards then it might be wiring.

I had a similar issue with my beastie when I first did the conversion and it turned out to be an issue with the start signal to the ecu and the poor thing thought it was cranking - no advance - low power and very hot exhaust.

[CrUZida]

Timing was checked last night.
8 deg with timing jumper installed, and 15deg at idle with no jumper in, moving further advanced when I revved it.

[CrUZida]

Checked VF1 and VF2 this morning after an EFI reset. Both were at 0V. Not sure why they aren't working ?
Maybe because its an auto ecu the shifter needs to be in PARK for it to work ? (CEL works fine though).

Also checked the narrow o2 sensors when I got to work. WBO2 was sitting on ~16:1 at idle, narrows were sitting on ~0.6V, which according to Stu's graph is about 14.3:1

Checked VF1 and VF2 again at work, still 0V.

[stevevp]

Crumbs, It was a long shot. I'm now back to a scientific mistrust of the readings/calibration from the A/F meter. My next step would be a trip to a EFI tune place as you suggested earlier just to get a reference A/F figure from a tail pipe snifffer.

[CrUZida]

I'll be fucking pissed off if my wbo2 isn't reading correctly.