Bentley vs scanner P-code definitions for P1092

[btrvalik]

My scanner (TorquePro) defines P1092 as pre-cat bank2 too lean, but the Bently repair manual says is pre-cat bank1 too rich. Since my fuel trims are +7 and +8 I'm assuming the Bently book is wrong. Anyone else hit this?

[80stech]

Have a look at Kevinkay's thread(s)

[btrvalik]

been on that thread - the real question is should I trust Bently or the scanner for the definition.

[80stech]

Neither and both, depends on how you look at. Like I tried to explain, you pretty well need to change the mixture manually(introduce a vacuum leak or change the regulator vacuum) and see which way the trim goes. And then of course tell us what you find out!

[80stech]

My guess would be that trim is on "rich" side(assuming that the software's interpretation is for "fuel" rich) to compensate for a lean "fuel" condition.

[upallnight]

A long term fuel trim that is in the plus means the engine was running rich.

A short term fuel trim that is in the plus means the computer is adding adding fuel to compensate for a lean condition.

What the computer is trying to do is get both fuel trims near 0. If the long term is rich it will take away fuel trim in the short term to try and balance the long term out.

If the long term is lean it will add fuel in the short term to try and balance out the long term.

That's is why when you make a statement like the fuel trim is + you need to also tell us if it is short or long term.

[Anhelenuk]

Go with upallnight