No Fuel Trims?

Barks

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Hello, Does anyone know what would cause the ME7.x ecu not to adapt the fuel trims? I have converted from a narrow band APY to a wideband BAM, disabled the rear O2 and VVT, but currently have no fuel trims (both at 0) or fault codes. Any ideas/pointers very much appreciated. Thanks
 
Um it has been a while, I am sure the N249 is resistored and tucked away in the coil loom, the VVT has been resistored and I dont the BAM CB ecu if I recall has a N112 (No SAI) me thinks, which one is the N118 valve? (and I don't know why return/enter key does not work on this forum, windows 8 feature???:)
 
Is the rear O2 sensor unplugged? if not try unplugging it...

If you didn't remove the pins for the N112 from the ECU plug it could still detect it being there (dunno for sure... ) I assume you still have the N112 plug/wiring in the loom... maybe worth plugging it back in a check block 001 to see if lambda is adjusting

<tuffty/>
 
...although if its not looking for it it won't know its open circuit... hummm.. the ME7.5 ECU will have the inputs for N112 as K03 cars have SAI... if its plugged in then try unplugging it, if not try pluggin it in...

Also... adaption is triggered by engine temp... not altered any of the temperature tables or disabled LTFT's in VCDS?

<tuffty/>
 
Take a look back at s4 wiki, all the deletes have been updated since you made the change to a bam . I think as tuffty says it'll be one of the rear 02 variables not set correctly.

If cdnws is set to 0, then it won't be Vvt. Bam has no sai. Evap deleted? Its only 3 variables. Rear 02 is the most likely.
 
Yeah no rear 02 fitted, I am pretty sure that the N112 was on the exhaust half of the loom that has now been removed and replaced with the BAM half so the N112 isn't fitted.................AFR current and request track each other.......... scratching my head really?? Paul are you running VVT delete?
 
No mate... managed to pick up a genuine (although waiting to see when it arrives) VVT unit for £110... so will be continuing to run VVT...

Considering how fussy the ECU can get when stuff is not connected then it could be anything... when you say no adaptions you mean block 001 is not showing lambda control? or just 0's in 032 all the time?

<tuffty/>
 
Take a look back at s4 wiki, all the deletes have been updated since you made the change to a bam . I think as tuffty says it'll be one of the rear 02 variables not set correctly.

If cdnws is set to 0, then it won't be Vvt. Bam has no sai. Evap deleted? Its only 3 variables. Rear 02 is the most likely.

I will have a look now Dan, cdnws is set 0, Evap has not been deleted, I need to have a look at the rear 02... cheers

(BTW Enter/Rerurn key now working in firefox!! Yay)
 
No mate... managed to pick up a genuine (although waiting to see when it arrives) VVT unit for £110... so will be continuing to run VVT...

Considering how fussy the ECU can get when stuff is not connected then it could be anything... when you say no adaptions you mean block 001 is not showing lambda control? or just 0's in 032 all the time?

<tuffty/>

Ah I see, I have a VVT which may be a option to fit (I mean take to to Bills to fit :) ) Sorry don't know about block 001 off hand but 0's in 32 all the time
 
Check block 001 while running... its a very important one for wideband fuelling tuning tbh... it will help you dial in fuel tables... that and injector on time.. just remember though... every time you reset fault codes LTFT's reset too...

<tuffty/>
 
Check block 001 while running... its a very important one for wideband fuelling tuning tbh... it will help you dial in fuel tables... that and injector on time.. just remember though... every time you reset fault codes LTFT's reset too...

<tuffty/>

Thanks for the pointer Paul I will have look tonight
 
Take a look back at s4 wiki, all the deletes have been updated since you made the change to a bam . I think as tuffty says it'll be one of the rear 02 variables not set correctly.

If cdnws is set to 0, then it won't be Vvt. Bam has no sai. Evap deleted? Its only 3 variables. Rear 02 is the most likely.

Cheers Dan, there is alot more that has been added for the Rear O2 delete, I will have a look tonight
 
Hello, On Block 001, Lambda is jumping around between -6 and -16 @ 65 Degc when warming up from cold and around -3 to +4 when up to temperature... On engine readiness it states that that Oxygen incomplete or failed I guess these are not disabled correctly?
 
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Sounds plausible... easiest way to check is to simply plug the post O2 back in... tbh all I have done on mine is CDKAT, CDHSH and CWDLSAHK (all set to 0) but left my probe in and connected...

<tuffty/>
 
I would but a can't get the barsteward plug out!! I will they just plugin it in freeair and see what happens
 
Dave, I'll send over a current bam file, you can check the deleted 02 , I know my trims work as I tested 550 injectors a while back on stock fuelling to see if over 25% the engine warning light illuminated.
 
Very kind of you Dan, Thanks,

This is what I did to removed rear O2, (or not as the case may be :)

06/07/2012 21:07:49 Scalar: CDKAT changed from 1.00 (0x01) to 0.00 (0x00).
06/07/2012 21:08:03 Scalar: CDHSH changed from 1.00 (0x01) to 0.00 (0x00).
06/07/2012 21:08:21 Scalar: CLAHSHE changed from 3.00 (0x03) to 0.00 (0x00).
06/07/2012 21:08:39 Scalar: CDLATV changed from 1.00 (0x01) to 0.00 (0x00).
06/07/2012 21:08:58 Scalar: CDLASH changed from 1.00 (0x01) to 0.00 (0x00).
06/07/2012 21:09:11 Scalar: CDLSH changed from 1.00 (0x01) to 0.00 (0x00).
06/07/2012 21:10:21 Scalar: CLAHSH changed from 3.00 (0x03) to 0.00 (0x00).
06/07/2012 21:10:49 Scalar: CLALSH changed from 3.00 (0x03) to 0.00 (0x00).
 
All sorted not, Fuel trims are back, both sitting at about -2% after a quick drive, The problem was that CLALSH was set to 3 not 0 at is clearly states on S4 Wiki, I obviously made for a **** up on the way somewhere. Thanks Guys
 
Not as of yet Dan, I need to give your TMD map a tinker and then a whirl, I will be sure to report back!
 

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