ECMlink GVR4 AFREst spikes

[Mytalonateyou]

Hello everyone.
I'm having some issues with my AFRest. During warmup the AFRest is spiking. I'm not sure of the cause.
Vehicle is a 91 Galant vr4.
16g turbo on SD with Omni 4 bar.
The Omni vacuum line is tied in with boost control, map sensor, and waste gate.

Look for advice or information to meditate this issue.

Anything helps.

Thank you

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[steve]

Welcome to the site.

My first guess is it's time to replace the MAP sensor. You'll need to actually post that log to get much more feedback. Attach it the same way as you did the image by using the "Add Photos" button but select the ECMLink *.elg file.

 

[gofer]

Your AFREst is spiking because your STFT's and AirflowPerRev values are checked out to lunch.

https://www.ecmtuning.com/demos/fueltrim.mp4

 

[Mytalonateyou]

log

 

[We're on Boost]

log

Yeah, like Steve suggested, it looks like your Omni 4-bar is putting out a junky signal quite a bit of the time.

For instance, 39 psi of boost at idle? That's what the log says from 339 to 364 seconds.
I see junky looking Omni signal in lots of other places:
613 to 652 seconds, 791 to 804 seconds, and 818 to 840 seconds.
After 840 seconds it seems to straighten out. It's pretty decent looking from 840 to the end.

So I would try replacing the MAP sensor.
Since the Omni 4-bar has been questionable lately for reliability, I'd try something different.
If you aren't planning on boost over 29 psi, I'd say try the 3-bar GM type MAP sensor sold by Ballenger Motorsports. $70. Read the Description. It's the same externally (same electrical plug and overall form) as the Omni so you can just swap it right in. In ECMLink on the ECU Inputs page you would use the preset called "GM 3 bar".

The Omni vacuum line is tied in with boost control, map sensor, and waste gate.

This is also not good though. Your MAP sensor and your wastegate actuator should not be tied together. The MAP sensor hose should come from the intake manifold, and the hose to the wastegate actuator should come from the turbo outlet or the lower intercooler pipe.

 

[Mytalonateyou]

Thank you everyone for the info.
I will start with correctly routing the vacuum lines and getting another log for any changes.

It is strange that the map signal settles after a little while. It seemed to straighten out after the engine was at operating temp.

I will get an update for everyone soon.

 

[steve]

@Mytalonateyou How did this turn out?