WBO2 shows idle AFR in the 17 to 19 range. Crusing and moderate throttle is high 14 and WOT is mid 13. Played with MAF table #1 today and couldn't make any headway with the lean idle. The car runs good, but I'm trying to do something with the stench at idle. Okay, what more information do I need to provide in order for the expert 165 tuners to jump in and help?
Thanks in advance!

 

Your in CL so the ecm will attempt to adjust the afr back to what the o2 sensor sees as 14.7. Doesn't mean that the engine is seeing 14.7. Numerous things can put o2 into the exhaust for the o2 sensor to see and the ecm to adjust for. Smell, throttle reponse, and plug color will tell you what the cylinders are getting.

You adjust the tables to get the blm/int into line and
to get the CMD afr to match the WB. Adjust the o2 constants to get the idle afr stench under control if your running a non stock cam. Addtional idle timing with non stock cams helps too.

The 8D tuning methods will apply to the 6e. But some of the tables etc will be different. If you can't figure out what's what. Ask about specific tables and constants.

Seen some reports of winter gas being worse than summer gas
in the smell department. Also seen reports of lean afr causing it too.

You need to datalog at various temps and list what your mods are.

 

Thanks Z69:

"Your in CL so the ecm will attempt to adjust the afr back to what the o2 sensor sees as 14.7. Doesn't mean that the engine is seeing 14.7. Numerous things can put o2 into the exhaust for the o2 sensor to see and the ecm to adjust for."

The O2 sensor and the WBO2 are in the same exhaust line separated by maybe 2 feet. The O2 sensor is in the left header collector and the WBO2 is in the exhaust line just before the right bank of cylinders ties in. Seems strange that there would be this much difference between the two sensors - what the O2 sensor thinks is 14.7 the WBO2 reports as 16 to 19, and yes, I have calibrated the WBO2 in air numerous times so I will assume it is fairly accurate. Maybe I should consider replacing the O2 sensor. Any recommendations on what brand sensor to shop for?

"You adjust the tables to get the blm/int into line and
to get the CMD afr to match the WB. Adjust the o2 constants to get the idle afr stench under control if your running a non stock cam. Addtional idle timing with non stock cams helps too."

Just reviewed some recent logs which were done after increasing the idle spark advance to 32. I need to do some more work as my idle blm/int is 150/118 and the block learn cell is 0. When you mention the CMD afr, do you mean what is listed as the "Target AFR" in TPRT? The Target AFR is normally always 14.73 unless in PE where it changes to 13.65. The WBO2 tracks well with the Target AFR of 13.65 when in PE. I'm not at all sure how to adjust the O2 constants with a 165 and TPRT. Do you mean the Target AFR values? I can find one constant called "Stoichiometric Air/Fuel Ratio" that I could change from 14.73. Is this what you're referring to? Where is the constant for the PE number of 13.65?

"You need to datalog at various temps and list what your mods are."

I tried to list the mods in my sig. What mods were you wondering about? I guess I didn't specify the cam and heads. The cam is 224/230 @ 112 lsa. The heads are Trick Flow 23 Degree, 64cc comb. chamber with 195/75 cc ports with 2.02/1.60
valves.

I'll be doing more tuning for idle blm/int and reporting back later.

Thanks.

 

Do a search on WB AFR or something.
Several posts on WB vs NB and what your seeing.
You might recommend one as a sticky if one is clearly good.
Your cam is probably fooling both o2 sensors.
The measure o2. Not AFR. Then o2 is correlated to afr.

An air leak could cause a split like that.
Always best to swap locations once to verify nothing odd is going on.

Leave stoich alone at 14.7x.
It is used for other things. Not what you are thinking.

AFS 74 IIRC for the heated NB sensor. The P/N is in the FAQ on my site.
Check your o2 cross counts and ask if they are good or bad.

Target AFR = CMD afr.

Once your MAF tables allow the WB to follow the target afr, you can change the PE %ch AFR vs RPM to make the actual wb AFR whatever you want. Lots of reading on this stuff.
You'll have to read the 8D stuff too.

IIRC there's a couple o2 constant stickies.
If not, I have a few marked on my other pc.

I've seen very few MAF users respond lately to questions.
If you ask specific questions about things and have 6e/MAF or something in your sig you'll get more answers.
And do lots of searches on the specific things first.
All of this has been covered in the last year or so.

 

CriSSes,

Try this thread. https://www.thirdgen.org/techbb2/sho...t=surging+idle
I have the same heads on my Xfire with a CompCams Hyd Rlr. The duration isn't as high as yours, but if yours is a flat tappet, then my roller acts more like a 228 flat tappet cam. And has a 108LCA.

 

Dominic - Thanks for the thread link. Lots of good information there. The cam is an SLP hydraulic roller. I think I need a higher stall converter to really take advantage of my set up.

Z69 - I made some changes in the MAF table #1 by increasing the gms/sec numbers slightly in the 10 gm/sec area where the car idles. This caused the BLM to change from the 150 range to about 128. INT is now also steady at 128. Block learn cell is 0. Looks good so far! Target AFR is 14.06 to 14.22. O2 sensor is 452 to 475 mv. O2 cross counts are increasing at about 2 per second. BPW is 2.26 to 2.55 msec. IAC is 13. WBO2 is reading 18.5 to 19.75 which seems to back up the cam overlap idle "fantom lean" situation. Plugs look good. Stench seems to have been reduced.

One question after reading all the information. With a MAF 165/6E car, does adjusting the MAF table #1 values do the same thing as changing the O2 constants as discussed in the articles which seem to pertain primarily to the SD cars?

Regarding your comment - "Once your MAF tables allow the WB to follow the target afr, you can change the PE %ch AFR vs RPM to make the actual wb AFR whatever you want. Lots of reading on this stuff." Gonna have to do more searching and reading about this. The TPRT 6E def. file has the table PE vs. RPM. Is this what you were referring to?

Thanks for your help!

 

????

Seems like you've got it in open loop. And your O2 sensor shouldn't stay in the middle at 450 if it's working and warmed up. INT should never stay at 1 number when in closed loop. Target AFR should be at 14.7 in closed loop. Wideband should read close to normal with that cam.

Try a heated O2 sensor. Maybe yours is cooling off too much.

Your PE Target AFR is a bit leaner than I'd suggest. What A/F does the WB read at WOT?

 

If you look on www.moates.net/fileman
There is a 32b Maf tuning file.
The 6E is very similar.
The big diff is that 6E doesn't have one table for fuel that
32b does. I forget the name.