Tuning Advice needed

**edfiero1** · 07-25-2015

Hi Guys, hopefully someone can share some wisdom with me.

I am using EBL Flash trying to tune an old Pontiac 4 cylinder running a dual throttle body injector, 4 speed manual. I am done a couple VE learns so far and am slowly correcting an over all rich condition. I know I need to continue doing this but after 5 'learns' I have two issues that don't seem to be getting any better.

1. While driving and pushing in the clutch, the engine will slow and often die. Idle is set at around 1000. If I am parked, it will idle fine. This happens at most every stop. Engine is fully warmed up. What do I need to adjust here? Since I appear to be rich every where it doesn't seem that I need any more fuel here.

2. Most every time I get on the throttle and hit 3000 RPM, I start to backfire (thru the intake I believe).

As I said, I know I need to continue with the VE learns to get the AFR where it needs to be but I'm not seeing improvement in these area's so I am wondering is there something else I should look at? I haven't done anything with Spark yet. Any rule of thumb to know when more spark is needed, or do you just raise it until it knocks?

Attached is a data log from my most recent run.

**RobertISaar** · 07-25-2015

the engine dying when the clutch goes in could be one of two things: a clutch pedal position switch not being detected, or should your calibration not use one, the IAC throttle follower needs adjusted so that when you let off the throttle, the IAC keeps a little further open than it does now.

**edfiero1** · 07-26-2015

I found a parameter in TunerPro called Stall Saver. I raised these values however that did not did not improve the problem with it dying when I push in the clutch.

**lionelhutz** · 07-26-2015

You might be in DFCO as you're coming to a stop and with no fuel to the engine when you clutch in and the RPM's drop it can't get out quick enough. I doubt it, but maybe.

You really need to figure out if that misfire is a mechanical issue or tuning. It could be a mechanical problem that is also causing the stalling. Also, you can't tune-out a mechanical issue.

**edfiero1** · 07-27-2015

I am pretty sure I see in the data log that when the clutch is in and the engine starts to go below the idle RPM, the IAC is opening up, as it should based on the stall saver. Should I command the stall saver to open the IAC more, or is there another setting that is more appropriate? I see there are multiple IAC settings.... and I never know if I should be trying to correct a problem by adjusting the timing.

**RobertISaar** · 07-27-2015

the EBL is running on its own code(I believe it's a "from scratch" OS from RBob), hard to say what exactly you need to mess with since what is available and how it is defined might be a bit different from what was used in GM code.

**lionelhutz** · 07-27-2015

Throttle off coasting right before the clutch is disengaged or something different?

What happens if you bring up the rpms when idling and then snap the throttle closed? What do the IAC counts do when you do this? There should be some type of throttle and/or speed following tables for the IAC that open the IAC as the throttle opens and/or the speed increases.

Is there some kind of idle timing table that is different than the main table?

Did you find any DFCO parameters?