IT LIVES! My Z/LE ZL1 + 1LE + 2SS = Z/LE ;o) LSA SC [COTW 2/09/15]

[zman1969]

Don they do have a tool, your gonna need to school me about swapping to E85 someday

[hammdo]

Originally Posted by zman1969

Don they do have a tool, your gonna need to school me about swapping to E85 someday

I do have the tools, just not enough room to get in there with it - very tight fit on the sensor .

NP on E85! Works great on my setup! Thanks Rich!

-Don

[hammdo]

Well, new position and sensor did not solve it. I did a run tonight -- logged again. You can see the signal coming and going here (this really shows how its coming and going):





Also had some '100%' readings too:




Now, this is just barely moving -- so the signal coming from the sensor is oscillating and the ECM is doing its best to keep up.

I received the new harness from Dave so I went ahead and installed it -- original, no kinks/pinched wires, and uncut - that will be the next test.

-Don

[ABADZL1]

Your commanded EQ is the same no matter what your sensor reads. Doesn't look like the issue is affecting fueling. Not in those pics anyway. There is a setting in the tune I believe, that adjust the rate of change for the alcohol EQ. Apparently your settings are slow enough your ecm doesn't react to it. I wonder if it's really worth worrying about.

And, is the pin on the white wire oriented correctly in the plug? It does matter which way it goes. Just a thought.

[hammdo]

I double cked the white wire before replacing the harness and it was correct:



Yeah, that oscillating doesn't appear to be impacting the constant reading, and it is at low speed too... I added it to the output so I could look for trends. It's happening so fast, I doubt, like you said, it's a problem.

Now that I have the new harness on, we'll see if it makes a difference. This data log was from the previous harness.

What I was looking for was possible 'air' in the fuel lines -- that would read 0. I wanted to see if air would get in from the 'suction' side of the aux pump.

I'll find out tonight when I data log again...

Thanks for the help Mark, it's a learning process for me...

-Don

[ABADZL1]

I dont believe those sensors react fast enough to pick up a little bit of air. And I'm not sure how you would pick up air from the tank. Seems weird

[hammdo]

Agreed -- but a loose line (hose) near the tank where you have the 'u' shaped stainless lines might -- just speculating really -- I'll wait and see if this harness solves the issue -- if not, then, a 'dedicated' 5v supply may be in order (I have 12v to 5v 3amp stepdowns -- very simple to setup) to eliminate any possible voltage interruption. I have that scoped out ;o)

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

If the voltages is interrupted, then this will make sure it gets a solid 5v signal in...

-Don

[ABADZL1]

If the voltages is interrupted, then this will make sure it gets a solid 5v signal in...

-Don[/QUOTE]

That's why I was wondering since getting power off a coil pack, maybe there is some "noise" causing that. Spark plug lead has a few joule's to it. Lol.

Just speculating.

Something else I thought of. If you had a voltage issue with the sensor, you would throw a code since that DTC is turned on. But if it's only for a nano second, ECM may never catch it.

I know this is going to bug the crap out of you until you figure it out.....It would me

[hammdo]

Yep, no DTC and that is what's bugging me. All are on. I'll find out..

It could be a wire break in the white wire leading to the ECM and thus no code. I replaced all the wiring so I'll see ;o)

-Don

[hammdo]

Still the same -- its as if when I get the speed above 70 and RPMs up, the ethanol goes to 0, then recovers when I let off.

So, new sensor, new wire harness, same problem. I'm going to verify the 'ground' is still good, but after that, I'll be making my own harness with its own power source. Outside of a loose ground, I don't see anything else.

I do get the fuel from the same place -- and I fill it up each night -- to be sure. Tonight, I went somewhere else.

Its acting like the voltage is cut off and there goes the ethanol content...

I'll do my step down and see what that brings me...

-Don

[ABADZL1]

I bet its radio interference from coils.

Need some shielded aviation wire?

[DSX Tuning]

I don't know how much water I'd put in the electrical interference from just the coil bucket. There's probably somewhere close to 2500 vehicles running this same style kit without issue (I've had one on my CTS-V for years in the exact same spot).

It's definitely an odd occurence, especially to have just recently started after working fine for some time.

In terms of aftermarket electrical devices, what's on the vehicle?

[hammdo]

ZL1 DRL, dual varimax intercooler pumps, electric vacuum pump (from a LLT), Aeroforce gauges with 2 analogue sensors. Aftermarket coils ( Sultan of Spark). Aux fuel pump. All of these have been on the car for sometime. New engine of course. Tried 2 different coil packs no difference. Checked the engine to ground, all tight.

I agree it's odd, there are lots of installs using the coil as voltage supply without issue.

I do have aftermarket coils though...

-Don

[ABADZL1]

Sultan of Spark. Lol. Try a stock coil maybe, just to see?