Help An Old Broken Down Tuner

CosmicArkie

CosmicArkie

Greenie N00B Member
Hello all you speeders.
I am a recovering... Nah, never mind. I'm still looking for a little more power. I enjoyed a Cosmic Blue '07 Speed 3 for 10 years and 100k miles while I was in Arkansas, hence the screen name. Some of you old timers may remember me. I certainly learned a bunch from you. I made the mistake of trading the Speed 3 on a CX-5 thinking I'd be satisfied with 187hp. Then they came up with the supercharger kit. I bit. I've spent the last month tweeking the VersaTune software. It has been a steep learning curve - not nearly as user friendly as the Accessport, IMHO.
That said, I've got it running pretty good. Trims are single digits; pulls smoothly. I haven't really hammered it yet, but it does impress. My issue is a random P0101 DTC now and then. Seems like shortly after restarting and pulling out (think stopping for gas) it will throw the lamp. Is there an easy way to tune it out? Logs don't have anything that jumps out at me, but I'm new to VT. Thanks.
 
What is the DTC description? I hate it when people post codes assuming everyone else will automatically know what they are.
 
P0101 is a mass air flow sensor code. Have you done the MAF Calibration or checked for any post MAF sensor leaks?
 
Enki said:
What is the DTC description? I hate it when people post codes assuming everyone else will automatically know what they are.
Click to expand...
Sorry, Enki, you're prolly the first guy I was thinking about asking this question. P0101 is "Mass Airflow (MAF) Circuit Operating Range or Performance Problem".
L337TurboZ said:
P0101 is a mass air flow sensor code. Have you done the MAF Calibration or checked for any post MAF sensor leaks?
Click to expand...
Yes, I have got a very smooth MAF curve worked out and trims in the single digits. Idle is smooth as glass and I am relatively sure there are not any leaks. It acts the same with two different sensors. I was raising the VE tables with the thought that the supercharger torque curve comes on _so_much_ lower that VE would necessarily change down low. Any thoughts? Thanks.
 
What voltage are you hitting? I know the Speeds can't go over 4.8v or they throw a code or shut off or whatever.
 
As I said, I haven't really pushed it - so far I've only run up to 3.55 or so. The last couple times the DTC popped up was when I was on a two lane road, in 4th(automatic) and accelerating out of a corner going from, say, 1700 to 2200 rpm at a moderate rate. This thing runs down the road in "D" at 1900 or so at 60, 2150 at 65, so this is right where I'll be driving around on the back roads. Load varies from 35 to 55, so not really pushing. If I could predict it I'd log it, but it is random as far as I can tell. Just wondering if there is any underlying theory I'm missing. I'm about ready to just block it, but I don't know if it would show up on the annual check.
 
Last edited:
The code itself P0101 is indicating an issue where the calculated airflow by the ECM doesn't match the actual air flow measured by the MAF sensor.

A loose clamp, broken vacuum cap or line, bad MAF calibration in the ECU could cause all of these things. Just cause your LTFT may be single digits doesn't mean that the STFT is within the range it needs to be.
 
Enki said:
MAFCAL goes to 5v yes?
Click to expand...
Yes, potentially, there are 5.0 volts, I just haven't gotten that high yet.
L337TurboZ said:
The code itself P0101 is indicating an issue where the calculated airflow by the ECM doesn't match the actual air flow measured by the MAF sensor.

A loose clamp, broken vacuum cap or line, bad MAF calibration in the ECU could cause all of these things. Just cause your LTFT may be single digits doesn't mean that the STFT is within the range it needs to be.
Click to expand...
The _total_ trims are single digit after adding and subtracting. As in LTFT holding at -5.5 and STFT varying from +3 to -3. The only place I can think of that I haven't looked at is the catch can plumbing. Let me climb under there and take a peek in the morning and I'll get back to you. Thanks.
Hey, you might have hit on what I've been wondering - what is the formula that the ECU uses to come up with the calculated airflow? Which tables or inputs?
 
Last edited:
I'm baaaaaaaaaaack.
Nothing to report re: plumbing issues. All clamps/hoses tight.
So, back to the calculations for the calculated airflow. I was under the impression that RPM/Load/VE were the tables that became the expected flow. Something else going in there? Thanks.
 
CosmicArkie said:
I'm baaaaaaaaaaack.
Nothing to report re: plumbing issues. All clamps/hoses tight.
So, back to the calculations for the calculated airflow. I was under the impression that RPM/Load/VE were the tables that became the expected flow. Something else going in there? Thanks.
Click to expand...
On the speeds, I believe that VE is only used as a fallback for limp mode and the like; everything else runs off of MAF.
 
PandaMS3 said:
This is all being done on a CX5?
Click to expand...
Yeah, I snuck in the back door when no one was looking. This is the most lively forum with VersaTune content and having experienced the helpful folks on the old forum I knew they'd be informative.
 
CosmicArkie said:
Yeah, I snuck in the back door when no one was looking. This is the most lively forum with VersaTune content and having experienced the helpful folks on the old forum I knew they'd be informative.
Click to expand...
Nah I wasn’t saying you don’t belong, I’m just impressed that your self tuning a supercharged cx5
 
Enki said:
On the speeds, I believe that VE is only used as a fallback for limp mode and the like; everything else runs off of MAF.
Click to expand...
Yeah, but its been a long time since I fooled with my Speed and I've slept since then, and I don't remember messing with VE. If its all MAF, I guess blocking is the answer. Or go down the scaling rabbit hole with a different sensor; without any guarantee it would solve the issue.
Thanks again.
 
PandaMS3 said:
Nah I wasn’t saying you don’t belong, I’m just impressed that your self tuning a supercharged cx5
Click to expand...
No problem, it takes more than that to wound my wrinkled old butt. I just wish the old forum still had the massively helpful library available. There really isn't too much difference in the tuning theory-wise, and we all worked through that years ago with the Standback and then the Accessport. The big difference is the change in the torque curve with the supercharger. This thing pulls like a V-8 from 1500rpm and up. Back in the day we would be waiting to get on the pipe up at 3000 or so.
 
Last edited:
Post your MAF cal. Depending on how you did you MAF curve (excel method) you might need to zero out some of the values at the lower voltages. You can take a datalog before starting the vehicle, and watch the MAF voltage for the lowest value recorded and basically zero out anything (-0.5 volts) under that value
 
Mfinlay04 said:
Post your MAF cal. Depending on how you did you MAF curve (excel method) you might need to zero out some of the values at the lower voltages. You can take a datalog before starting the vehicle, and watch the MAF voltage for the lowest value recorded and basically zero out anything (-0.5 volts) under that value
Click to expand...
That's usually a crank angle sensor code and it's 0.9v and lower that needs to be zeroed IIRC.
 
You must log in or register to reply here.
Back
Top