Tough knock question

[Pronto]

CT

 

[Eric Stage I]

Yanked the translator and am now on a tt 91 street chip with 93 in the tank, with the factory maf. Got my idle to settle down but all the same problems are still present lol. Idles about 1.5 AFR leaner than it should, and is somehow still at 9.2 9.3 9.4 at WOT with about 15 psi boost. How... This is with translator, without translator, stock maf, ls1 aluminum maf, ls1 plastic maf, TT alky chip, TT street chip, and Bob Bailey alky chip. It doesn't matter. It idles lean and does everything else rich. I have another ecm, stock, not set up for power logger. Should I try that? Or no.

Take the WOT adjustment in the chip down about 10% and do another log. You might have to go down further. Assuming the wideband is right, you are just not making the power I would expect from your setup, so it's not using the fuel I would expect.

The idle BLM cell is too high. Need to figure out why. Could be the MAF is reading to low, or you have a vac leak somewhere (including the PCV). I think some of your other cells will come up higher too, once you drive it around more.

You keep saying it's rich "everywhere" except idle, but it's not. Idle is fine, driving is fine, it's only rich at WOT. The idle will richen up a little once you figure out why the BLM is high. I have the BLM limited to 145 in that chip, so it has hit its limit.

Eric

 

[Turbo6Smackdown]

Ok, this makes sense. So from this I'm guessing that the lean idle and rich everything else are two separate exclusive problems? It seem that way now. Your take?

And by "not making the power you would expect from my setup" means what exactly. My boost is what I think is maxed based on pump octane. I couldn't raise the boost anymore anyhow. So with this consideration, isn't my combo at max power output for my my specified octane?

 

[Eric Stage I]

But, you're saying it again... "lean idle and rich everything else". In the log, the idle A/F is fine, and it's only rich above 12psi. Are we looking at the same log?

Here is your car idling:

Here is your car on a steady cruise:

Here is your car at WOT:

The AFR is ok until you get up over approx 12psi. The engine may not be moving as much air as I expected for the parts you have, so reduce WOT fuel to lean it out.

The idle BLM is too high, which can cause some funkyness when switching between cells. Figuring out why the BLM is high can be tedious at times.

Regards,
Eric

 

[Eric Stage I]

By the way, its not a problem for me to tweak the chip to lean out WOT. However, its better for you to adjust the WOT parameter until you get it where you want it, then I can see exactly how far you went.

 

[Turbo6Smackdown]

Yes, same logs. I can see on my gauge when I slowly roll into while cruising, the gauge dips into the tens. Always. See where that black line is in the bottom log? That's the beginning of me depressing the throttle. At that very second sure, the afr is 10.8, but when the car actually starts moving a little quicker, you can see under medium load when the mph and maf start to rise, the afr plummets. All my logs are that way. The AFR is always indirectly proportional to speed,rpms,load,maf, & tps. If a target AFR of 10.8 is slightly rich (for safety I presume) for WOT, shouldn't car then NEVER dip below that for light and medium cruise then? Just asking, because I've no clue of the intricacies of fuel tables.

By the way, its not a problem for me to tweak the chip to lean out WOT. However, its better for you to adjust the WOT parameter until you get it where you want it, then I can see exactly how far you went.

Ah ok, cool. I like that idea. So when I lean it out a little, post another log? Or send the chip back.

 

[Turbo6Smackdown]

Another question. If a chip was cut for a 206/210 cam, but there was a stock cam in there, what would that do, to both idle and wot?

 

[Eric Stage I]

Yes, same logs. I can see on my gauge when I slowly roll into while cruising, the gauge dips into the tens. Always. See where that black line is in the bottom log? That's the beginning of me depressing the throttle. At that very second sure, the afr is 10.8, but when the car actually starts moving a little quicker, you can see under medium load when the mph and maf start to rise, the afr plummets. All my logs are that way. The AFR is always indirectly proportional to speed,rpms,load,maf, & tps. If a target AFR of 10.8 is slightly rich (for safety I presume) for WOT, shouldn't car then NEVER dip below that for light and medium cruise then? Just asking, because I've no clue of the intricacies of fuel tables.

Yes, I mentioned that it only goes rich above 12psi. I can't find anywhere in that log where it dips into the 10's when you slowly get into the throttle. Can you show me where you are talking about? I'm not talking about when you let off the throttle, or any of the transitional stuff (non-steady state).

In response to your question about never dipping richer than 10.8, yes that can happen, its common during transitional areas to have rich or lean spikes. Try to only pay attention to steady state conditions for now.

The cam difference will have little effect. It might be a tad richer at higher rpm, but not what you're seeing.

 

[Turbo6Smackdown]

They're in some of the other logs but since you said to not pay attention to that, and only steady state stuff now then I will. So by steady state you mean cruise control set on 45 and cruising for a while, or wot for a full run I'm guessing. Right?

 

[Turbo6Smackdown]

Got another question. During some of my WOT bursts, while looking on the powerlogger files I see a C/L. Does that represent closed loop? Am I really running off of the oxygen sensor during these runs? And how accurate is the vacuum reading the powerlogger files? When it says I'm idling at 17, am I really? Or is it a representation.

 

[Turbo6Smackdown]

Anyone? Am I really running closed loop?

 

[Eric Stage I]

No, the factory code may show closed loop at full throttle, but its not. It was sort of a semi-closed loop, because it used to use the last BLM cell and apply it at WOT. But modern chips lock the BLM at 128 (or make it adjustable).

 

[Turbo6Smackdown]

Oh ok, cool. Thanks for your help Eric, I appreciate it. As I do everyone else in this thread, thank you.
What about that vacuum that's showing on the logger. Is that accurate?

 

[Eric Stage I]

Yes the vacuum should be accurate, as long as the MAP sensor is good.

 

[Turbo6Smackdown]

Wow, so according to John Spina 15 inches is pretty much standard, right?

 

[tonka]

Look in the help section of your PL, there is a command to zero the MAP signal with key on engine off. There can be a certain amount of error to the reading depending on barometer on a given day, not a lot but 17 could really be closer to 16 or possibly 18....

 

[Turbo6Smackdown]

So could this mean I don't have a lot of vacuum leaks at idle? My mity vac shows just about the same thing as well.

 

[ITSAV6]

check the pcv and all the vac lines, won't hurt I replaced quite a lot of mine that looked ok until i looked closer and bent them, lots of cracks. I bought mm sized vac tubing and used small zip ties to keep them secure. Had the pcv not pushed in the grommet and it took a week to figure it out, acted really screwy at idle and wot.

 

[Turbo6Smackdown]

Done last year. ALL my lines are new and zip tied. Tight too. PCV is the good one from RJC, all that's zipped too. I vac tested every piece before I installed it too. Then I vac checked all the lines after I installed them too. EGRs sealed. Line going to the egr is epoxied on the insides as well. Car idles at 16-17 inches 2 hours ago. Funny thing though, it raised up an inch after I removed the translator. Odd.
Gettin' my alky chip reburned. Finishing the last of my sensor change over, along with a new maf coming tomorrow. Going to try that with my old translator, and a new one too. After that, going to send in the tb/plenum to throttlebody.com for a work over. Maybe my shaft seals are whooped. Can't hurt. That way I KNOW the seals there, along with the tb to plenum and plenum to manifold seals will be good too. After that, I can't think of too many more places where air could be leaking in. That's ok, I have a feeling this last round of mods is going to take care of most of my worries.

 

[Eric Stage I]

PCV is the good one from RJC, all that's zipped too.

The last log you did had the idle BLM at 145. I find this is very common when people are using these check valves. It may be allowing too much flow on your car. You can test this by blocking off the PCV completely and see how far your idle BLM drops (you might want to reset the ECM and let the BLM's learn over again). If it drops a little, like 4-6 numbers, it should be ok. If it drops approx 10 or more, then it's flowing too much and needs to be restricted.

Eric