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Tuning Advice Needed on new build

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thearkatek

10+ Year Contributor
153
1
Jul 29, 2012
Saint John, NB_Canada
Hey all,

Before I get into the issues I'm having I'll post my car info.

92 Talon TSi AWD
Freshly rebuilt 6Bolt 2.3L Stroker (Eagle Hbeam rods, Ross Racing 9:1 Pistons)
Stock head
Garrett T4 Turbo
GM 3" Maf set up as blow through right before the TB
MAFT configured to 440cc injectors and zero'd out
FIC 1050 injectors (flow tested by FIC last fall)
Innovate LC1 wideband
Link V3 Full

I have verified base timing and the only boost leak I have is a tiny one in the compressor seal of the turbo (before the MAF). Did a compression test and all my cylinders were 190 +/- 5 psi. The engine has approximately 50km on it since the rebuild. Oil pressure is strong and mechanically I don't see or hear any signs of a problem

Now the problem I'm having is that my AFR's are all over the place and any time I go into open loop the actual AFR is waaaaaay richer than the AFRestimate. So much that I have to stay out of open loop for fear of washing the cylinder walls.

I've tried to do some cruises and change the maf compensation but something seems way off to me.

When it idle's after it's warmed up it cycles wildly and randomly takes big jaunts either rich or lean. Check out the attached log to see what I mean. I have already ordered a new LC1 sensor to be safe but I'm wondering if anyone has seen something similar to this.

I'm thinking about trying my old stock MAF to rule out the GM MAF and MAFT.

Any suggestions would be really appreciated!!

Thanks,
Nick
 

Attachments

  • NickFowler.2014.07.12-04.elg
    1 MB · Views: 58
Nick... Your MAF signals look pretty normal, and the compensation curve does also...although it's a little lower than some. But, I don't see anything in the MAF that jumps out at me.

For the most part, the AFR looks about right too, except for some random lean spikes. Do you have a factory O2 sensor you can hook up and compare to the WB? What happens if you lock it in open loop?

The only thing that looks suspicious at a quick glance is the TPS adjustment, but I don't think that is causing an issue. Still, you may want to measure the voltage and make sure it is mechanically adjusted correctly, and then use the link tool for fine calibration.

Make sure to get some good engine breaking/deceleration done before worrying too much about dialing the tune in. ;)
 
Thanks for the response dude. Yes I'm doing my acel/decel break in, but any time I want to give it a bit of load it drops down to like 9:1 or 8:1 and I'm worried about washing the cylinder walls.

That and the amount of Grey rich some that is coming out is worrying.

I also thought it was strange that the wb signal is varying so much.

As far as the coolant goes I have two slim fans that move quite a bit of air. Should I maybe try a new thermostat? Funny cause the gauge is reading slightly under the mid way mark during normal driving.

I'm just ultra paranoid because of the amount of bad luck I've had this far LOL.
 
Lock the ECU in open loop after it's warmed up, and do a short cruise, 2-3k rpms. Watch the WB to make sure it doesn't go crazy lean or rich, and get a log. I'm curious to see what it looks like when the ECU isn't cycling around a simulated O2 signal.

The stock coolant temp gauge is useless....don't trust it.
 
Last edited:
Open loop log. I don't know why, but in closed loop as soon as I let off the gas (like if I come to a stop light) there is a huuuuuuuuge plume of grey smoke and it goes super rich before evening out again. Yet in the open loop log it idles super lean...
 

Attachments

  • NickFowlerOpenLoop.2014.07.12-01.elg
    459 KB · Views: 49
Last edited:
shit fuel - 91 octane. It's all I can get.

Got the pressure set to 40psi, but also have Link set to 40psi.
 
I dug out my old NGK AFX Powerdex Wideband kit.

Gonna try to get it wired into the car tomorrow and we'll see what happens.

Thanks again for the help my man!
 
It was the Wideband!!

Working a lot better now. Still blowing huge clouds of grey smoke after coming to a stop. I even got into a tiny bit of boost tonight and besides the phantom knock from my exhaust hitting the frame it worked quite well.

I'm gonna try and fix the exhaust issue tomorrow so I can start actually tuning.

Here's a short log of me cruising around.
 

Attachments

  • NickFowler.NewWB.2014.07.14-01.elg
    154.9 KB · Views: 47
any thoughts as to why it keeps going rich as soon as I let off the gas? I have my BOV before the maf.

EDIT - I see that my throttle position never drops below 1%. Maybe that has something to do with it. Tomorrow I'll readjust the TPS and see if she's still blowing smoke. The only thing is that the simulated IdleSW is still triggered at 1% so I'm doubtful this will fix it.
 
Last edited:
So I think I've figured out the issue. Checked my turbo and it has a ton of slop. Ordered a rebuild kit so I guess I'll be out of commission until that arrives. Hopefully that will solve the smoke issue.
 
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