Block learn maxing out

[myredprky]

Help please,I have a1227727 ECM which has been running fine but now with a wideband innovate gauge fitted the afr is running at 10.5 to one and the ECM blocklearn is maxing out at 160.The oem narrow band 02 is still insalled with the wideband 02 fitted across the pipe from it. The ECM is also dropping from closed loop to open loop until the engine has run for over 20 mins.I have checked all connections and all seems well,fitted a new 02.In open loop the afr is running around 15.1 to one but as soon as she goes closed loop the block learn rises and afr drops to 10. The 02 crosscounts is about 3-4 per second but the voltage only changes from around 450mv to 600mv
can anyone spread some light on this please ????

[34blazer]

so the narrowband O2 readings are 450-600 while the WBO2 is 10:1? single wire narrowband?

a few months ago I had a similar problem. Driving home from work one day I noticed that my BLMs were creeping up, eventually maxxed out. Got it home and found that the signal wire from the narrowband was rubbing on an adjacent coolant pipe(metal), wore thru and was shorting out. This caused the readings to drop drastically.

[myredprky]

Thanks for you reply but I have rewired the whole 3 wire 02 this evening direct from the ecu but with no joy !!! The blm is still maxing out!!!

[34blazer]

Thanks for you reply but I have rewired the whole 3 wire 02 this evening direct from the ecu but with no joy !!! The blm is still maxing out!!!

what is the voltage from the NBO2 when the WBO2 is reading 10:1?

[RobertISaar]

from the sounds of it, you either have a dead/dying narrowband/wiring or the wideband is lying to you. based on the ECM not wanting to stay in closed loop, it sounds like the narrowband is the issue.

[EagleMark]

Help please,I have a1227727 ECM which has been running fine but now with a wideband innovate gauge fitted the afr is running at 10.5 to one and the ECM blocklearn is maxing out at 160.The oem narrow band 02 is still insalled with the wideband 02 fitted across the pipe from it.

Is this all that changed? Are both sensors in same pipe? Are you saying the sensors are in same pipe across from each other and now the problem started?

Vacuum leak will cause lean and add fuel.

Exhaust leak before O2 sensor will cause lean and add fuel.

In open loop the afr is running around 15.1 to one but as soon as she goes closed loop the block learn rises and afr drops to 10.

SO the problem is the O2 sensor feedback.

Sometimes guys find they have an issue with one cylinder when O2 is on one bank and WB is on other bank... Read all spark plugs?

[myredprky]

It has two 02s fitted,one narrowband and one wideband.they are both fitted 180deg from each other in the y pipe under the bellhousing both reading gas from all 8 cylinders.One thing I hav now spotted is the blm cell boundries in Tunerpro is completly different to all the other bins I have.instead of ...low 900 rpm...mid 1500 rpm...high 2000 rpm I have....

low 900 rpm.....mid 2500rpm ...... high 5250 rpm ?????
could this have an input to this ????

If you start her up when warm she will idle great 15.1-1 afr then go closed loop and stay fine till you blip the throttle then all hell breaks loose when she returns to idle,the blm rise mixture goes rich 10.5-1 co 8.5% and hc hits just under 3000,
narrowband 02 to ecu on tunerpro is reading between 550 and 750mv

Please help !!!!!aaaahhhhh

cheers IAN

[EagleMark]

That's weird! Something is wrong? If you post a datalog and bin I'll look for an issue. Start the log warmed up, do a little drive, and make it do this problem.

What's the motor specs, injector size and fuel pressure? What bin did you start with? How far did you move O2 sensor from factory position?

[34blazer]

It has two 02s fitted,one narrowband and one wideband.they are both fitted 180deg from each other in the y pipe under the bellhousing both reading gas from all 8 cylinders.One thing I hav now spotted is the blm cell boundries in Tunerpro is completly different to all the other bins I have.instead of ...low 900 rpm...mid 1500 rpm...high 2000 rpm I have....

low 900 rpm.....mid 2500rpm ...... high 5250 rpm ?????
could this have an input to this ????

If you start her up when warm she will idle great 15.1-1 afr then go closed loop and stay fine till you blip the throttle then all hell breaks loose when she returns to idle,the blm rise mixture goes rich 10.5-1 co 8.5% and hc hits just under 3000,
narrowband 02 to ecu on tunerpro is reading between 550 and 750mv

Please help !!!!!aaaahhhhh

cheers IAN

10.5:1 AFR would be over 900mV on the narrowband, theres something wrong with the NBO2 or the circuit....or both.

[myredprky]

Thanks for you help guys.....engine spec is as follows
new zz4 block
new Eagle crank and rods
kb flat top pistons
Comp Cams extreme energy computor controlled roller cam and followers
Edelbrock heads
Accel base
Speed and marine twin port runners
ported penum
Edelbrock BBk 58mm throttle body
30lb bosch injectors
Headman headers
3" stainless exhaust.
This motor has been running fine but has now started doing this....torquey finchy.bin nhghghgh.xdl
Have attached my bin file and latest datalog (i think) dont realy know how to do it so I hope its worked..

Cheers IAN

[myredprky]

Just thinking, I may have a go at taking out the nb02 and use the programmed output from the wb02 into the ecu see what happens...

again boys and girls many many thanks for all your inputs..

Cheers IAN...

[EagleMark]

Just thinking, I may have a go at taking out the nb02 and use the programmed output from the wb02 into the ecu see what happens...

Cheers IAN...

Oh no! That will be worse, I have yet seen anyone have luck with simulated narrow band yet....

For now you could just run Open Loop. You said it was running well and or tuned? That's a lot of motor to run a stock chip. You have a wide band to watch AFR or Lambda is OK, so run OL, learn to tune from WB for now.

I'll take a look at your bin and log later when I find time, we'll find out what happened?

Back to WB install... is that all you did and this happened? Sure there's no leak there?

[myredprky]

I have now connected the narrow band output of the wide band to the tpi ecu all seems to be running well ????THe trace of the 02 on the datelog is much better but still not what I would call great..
I will do another datalog later this week and post it here if any can help..

Cheers IAN

[EagleMark]

Let us know what WB and how you have the narrow band simulator set up... if it works, most crash after not to long because of no switch points and set's error codes.

I see some issues and one you mentioned earlier in the way the BLM is set up.

First idle is horrible, 650 -800 ish RPM and 60-70 MAP? Depending on your cam specs need 900+ RPM idle and spark advance at idle is like 20*, need 23+ and that will get idle MAP down to at least 50 or lower.

Back to the way BLM is set up, right now everything is in same cells, idle, off idle, load etc... look at the way BLM learn cells are set up.

					;---------------------------------------------
					;
					;                   _______|______|_______|______
					;                          |      |       |
					;                     12   |  13  |  14   |  15    
					;                   _______|______|_______|______  HI MAP 81 Kpa
					;                          |      |       |
					;                      8   |  9   |   10  |  11     
					;                   _______|______|_______|______  MID MAP 58 Kpa
					;                          |      |       |
					;                      4   |  5   |   6   |   7     
					;                   _______|______|_______|______  LO  MAP 18 Kpa
					;                          |      |       |
					;                      0   |  1   |   2   |   3
					;                   _______|______|_______|______
					;                          |      |       |       
					;     750   LO RPM   ______|      |       |
					;                                 |       |
					;    1800   MID RPM  _____________|       |
					;                                         |
					;    2600   HI RPM   _____________________|
					;
					;---------------------------------------------

After you get some idle quality going it should be 900 to 1000 RPM and say 55 MAP, well you'd want the BLM MAP and RPM like 1000-1100 and MAP 60-65, that will get idle in idle cells. Right now your idle is in cells 8,9 and 12... along with some driving...

Then the next set to like 2000 RPM and 80 MAP, third set to 3500 and 95 MAP. This will get BLM learn cells divided into how the engine runs, idle, off idle and load. There is no BLM learn for PE so WOT is not in there.

Back to idle, you've got a very aggressive spark advance table and with the surging idle the spark advance is changing from 19 to 29 advance with only 100 RPM change. The Closed throttle spark table looks good for a cam, but actual timing looks like it's coming from spark advance table. This may be do to some closed throttle qualifiers like RPM, MAP etc...

Back to the very aggresive spark advance table, is your knock sensor working? Some of your decel areas are more then allowed by ECM because oif limits in space between terminals in cap. You also still have some adders as well? Cold spark is adding and PE is adding... there's an initail 5.98* and the spark latency table looks to be a large cap HEI which is good if that is the distributor you have.

HTH!

[myredprky]

The wide and is an innovate mt gauge and yes I'm running a large cap hei dizzy.
is modifying the blm cells and the idle something that you could do for me on the bin you have off my post ( tried to read and understand what you are saying but it seems a little complicated for me at the mo ). I have copied the blm cells over from a stock super aujp bin but I understand what you are saying about my idle not being in the right cell . I will read again tommorrow and try to understand it a little better... 11.30 at night now here in the uk ...


again many many thanks for all your help. Ian