Hello all, and thanks to anyone in advance...

I am having issues getting my LT and ST BLMs to lock at 128 in PE mode. I am using Tuner Cat and Datamaster on my 95 OBD1 Z28.

I couldnt understand why I got slower at the track as night fell and it got cooler out. Turns out I was lean to begin with and when it got cooler it only hurt more.

On my datamaster logs, when I go WOT, it goes to cell 15. The LT trims go to 128 and so do the ST trims at first, then above 3000 or 3500rpm the ST trims start jumping around in the 130s and 140s. AS SOON as this happens my O2 MV's drop from the high 800s to 500 and below. Sometimes as low as 100s. Which to me is very lean. The correlation between the ST trims jumping and the O2 MV drop is consistant.

Back to the tuning. At first I was tuning only using the EE definition file that came with tuner cat. I thought this was the problem, so I found a copy of BLM locker and ran it. The tune would show up as being locked, but after I programmed the PCM then read it, it was unlocked. When I logged a run the BLMs were doing the same thing.

I then Emailed CATS and explained my situation. They told me I needed their EEL definition file to lock the BLMs and provided a link and password for the file. I downloaded and installed per their instructions, Picked EEL in TunerCat, loaded my tune, again made sure it was set to EEL, and programmed the car. When I went for a ride the BLMs went to 128 and fueling seemed normal. Then about 3500 rpm or so the ST trims started jumping and it went lean again. I tried adding fuel up top to compensate and, maybe its just me, but it seemed to make the BLMs jump higher like it was pulling more fuel.

Can someone help me here? I have no clue where to even start on this.

Thanks guys and girls...

 

Make sure your settings for Wide Open Throttle are correct for what you are doing.

 

They are...it is going into cell 15 when WOT

 

BLM cell 15 (high RPM, high MAP) is usually, but not always, the last BLM cell you are running in before you go into WOT (AKA: PE Mode). When you enter PE mode the ST BLM's stop updating and stay at 128, the LT BLM's stay at the last BLM cell setting and do not change. The o2's stay high up in the high 800's to 900 Mv. range. In PE mode the fueling AFR is controlled by the PE tables and the last BLM cell LT readings. Not sure what scanner or s/w you are using, is it possible for you to view the engine status bits. To see if you are in PE mode can you look at the engine status bits. 'PE Enabled' should come on, followed by 'BLM Enabled' going off. The "% TPS Threshold for PE Vs RPM Vs Coolant Temp" is one table that controls when you enter PE.

 

Bob, thanks for your reply. I am using DataMaster to log the PCM while driving. I do not see anywhere on it where it shows if I am in PE mode. Is tehre another program that would show me this?

Ok, UPDATE, while staring at all the tables in CATS I slowely went through all my constants again. I found that the "coolant temp thresh hold for WOT" was set to 151C. This must have been done accidentally somewhere along the way. If I am right, this was keeping it from going into PE unless the engine got that hot. Which it never would. I lowered it to the same temp as the closed loop thresh and will try it tonight after work.

Hopefully this is it and I could get some consistant fueling.

 

Looks like Kevin nailed this in post #2.... To view PE Mode and BLM Enabled in Datamaster go to yellow status indications in upper right of main screen. Double left click in any cell and a pop-up will appear, scroll through the pop-up screen and find BLM Enabled, double click on it and it will now be displayed in cell you double clicked, you can now see it come on and off as you step through your log, repeat for PE Mode.

 

Well the constant I changed was not the problem. I lowered that "cool thresh" and it made the car stay in PE mode all the time. This resulted in a check engine light when coasting. I put the constant back and the car ran normal but is still having the issue with the ST trims jumping up in the 130's and 140's at WOT making it lean...im lost

 

Can you post up or e-mail me a copy of the Datamaster .uni and a copy of the .bin file you have loaded ? I'll take a look at the settings.

 

Bob I emailed you a few logs and my tune...let me know you got them, if you need anything else, like mods and such, let me know. I really appreciate it.

 

sub

 

Sub?

 

I was subscribing to the thread so that I'd be notified whenever replies were posted. I have a similiar situation. Please let us know if you make any headway

 

Oh ok sorry...

After reviewing my Datamaster logs more, The PCM is definitly going into PE or WOT mode and at the same time that happens the BLMs get disabled.

So now I am really lost, if the ST trims are not supposed to adjust when in PE mode, then why are mine? The LT trims lock and the ST trims keep pulling fuel.

Hopefully Bob has an idea to help...

 

I looked at the three logs, and scanned your .bin file and can't see why your PCM is doing what it's doing. You go into PE mode BLM' are disabled, but your ST BLM's keep updating, and the O2 voltage is still pulsating instead of going up and staying in the high 800's as they should during richer PE fueling. The ST BLM's are signaling a 10% lean mix (135-140). Looks like the PCM is keeping the AFR at stoich (14.7 AFR). Your PE tables are set up to 12.7 AFR at 5K rpm but they do not seem to be activated. To me it looks like a bad PCM load or some sort of glitch in the s/w or maybe a weird setting I can't identify. I've never heard of definition file EEL, it's not listed in the TunerCats web site, I also wonder if loading the BLM locker possibly messed up the PCM s/w load. Noticed your injector DC is up in the 80% range when you are running WOT, and the injector constant is set at 25.38 lbs, what are your mods, what injectors ? Do you have an old virgin stock PCM '95 M6 .bin file you can try to see if the s/w is the problem

 

Bob, first off thanks a bunch for taking the time to go over my stuff.

This tune is based off an initial tune from Bryan at PCMforless for my set up which I have been tweeking on ever since. I might still have that unlimited update deal he had but I bought it in like 2003.

When I noticed the STs updating I ran BLM locker on it since I didnt think it was locked. Same result. I then Emailed CATS and they sent me a link to this EEL definition file. It is the same as the $EE but the L stands for locked BLMs.
Its their way of locking the BLMs without using the BLM locker program.

I believe I have a stock 95 bin on my old tuning laptop, which has a smashed screen, so maybe if I hook it up to a monitor I could get it.

The injector constant came like that from PCMforless I believe.

My mods are...CAI, stock TB and intake, X energy 224/230 with 1.6rr's, Pacesetter mids (soon to be LTs), no cat, hooker cat back, reasonably new GM opti with a MSD coil and wires. Stock injectors and fuel pump.

I dont know what else to do. No wonder I was only running 13.1's @ 108 with a 2.0 short time...need to get some fuel in this thing.

It a shame your car is a A4, cause besides the cam and gear our setups are very similar and I could try your tune.