What do I have going on here? (Chrome/ECUFlash/Evoscan)

[RealMcCoy]

Car is a 96RT/TT with ECU, harness, and drivetrain from a wrecked 99VR4 swapped in. So in essence, we're working on a 99 VR4.

I am having issues with the scaled sensor outputs for the EVO X MAP, and AEM UEGO on pin 93.

I thought I had the scaling for both correct in ECUFlash, and the correct formulas in EVOscan, but both sensors are reading bizarre numbers...

With known voltage values input, the MAP outputs the following:

0V = 14.86 psi
.5V = 5psi
1.5V = -1.3psi
5V = 5psi
2.5V = 7psi
5V = 32.7psi

The UEGO gives you this:

0V = 7.06 AFR
.5V = 8.0 AFR
1.0V = 8.8 AFR
2.0V = 7.2 AFR
3.0V = 12.9 AFR
4.0V = 9.9 AFR

Here's screenshots of ECUFlash scaling and Evoscan screen: evoscreen2.jpg flashscrn.jpg


I know I overlooked something stupid... Just not grasping it right now.

I also know there's nothing wrong in the car or ECU. If I hook up a normal scan tool, and let it think it's looking at the MDP and FTP sensors, it interprets the voltage inputs correctly...

[Dougal]

My evoscan formula for Wideband is different to yours. I am using the AEM 30/4100 UEGO

mine is x*0.0627+6

looks like my scaling in ecuflash is different also.

Mine works for my no worries - matches the gauge perfectly.

wideband uego ecuflash.jpgwideband uego.jpg

[Greg E]

You're not supposed to change the scaling in evoscan. I set it up so the ECU would do the math for you and all you had to do was scale the voltage in ECUFlash, flash, then log it.

[striker2]

My settings match RealMcCoy's (I never changed EvoScan) and it logs perfectly.

[RealMcCoy]

You're not supposed to change the scaling in evoscan. I set it up so the ECU would do the math for you and all you had to do was scale the voltage in ECUFlash, flash, then log it.

I thought that was how I did it.... Did you see something there to the contrary? I'll have to go back and look in the laptop in a bit...

[RealMcCoy]

I've been over it a couple times now... Opened the original Chrome ROM and compared it to mine looking for anything I may have changed inadvertently, and looked over Evoscan looking for something I could have messed up. The only difference I was able to find was where I changed the scaling in the ROM.

I'm honestly stumped at this point....

[RealMcCoy]

OK, still getting a headache over this....

Today I removed my current version of evoscan, downloaded and reinstalled the previous version (v2.9.0023). Made sure I touched nothing, selected the items to log, and still got the same readings... That rules out a bug in my version, and anything I could have screwed up in it.

I reinstalled v2.9.0100, proceeded to build a new ROM, and flash it into the car. Again I was careful to touch nothing but the necessary peripheries, and set the scale for the wideband and MAP.

Still got the same thing...

The ECU is receiving the correct voltages, all the grounds are verified, if you hook up a normal scan tool and let it think it's looking at the MDP sensor and the FTP sensor, it interprets the input voltages correctly.

I have absolutely no idea why I'm getting crap data out of Evoscan....

[Unlogic]

I never managed to get my Chrome ecu to properly read my aem wbo2 so I conneted it to my LCDBC instead.

[RealMcCoy]

I'm not an idiot, but I play one on the internet....

Fixed the wideband issue. Must have looked directly at the problem a dozen times or more and didn't see it. WidebandScaled was not selected by default in the Chrome ROM. Wideband was pointing to AFRWideband, which has a completely different formula.

Still haven't figured out the MAP issue yet... I really thought whatever was going on was going to be a common problem causing both. Didn't think I would be looking for two separate problems.

If anyone has an idea where to look, let me know...

[Greg E]

Can you verify A1 in the MUT3 table is FC45 in your ROM?

To be honest I'm not sure how or why you're trying to send voltage into the pin to see what data comes out. Hook up the sensor, flash the scaling, hook up a mechanical boost gauge, run it into the cab temporarily, go for a drive and compare the two readings. It'll work as it should.

Also trying to understand where AFRWideband comes from.... It's been a few years since I put this together but I only remember having these 3 in my evoscan file:

AFR map which is the current value in the fuel table
Wideband scaled which is thru pin 93
External Wideband which is thru the serial port of your laptop