First fire up stumbles. COS3 80lb 5.3L ls6 cam

[jay_rich]

Hey guys,

Im wondering if anyone can take a look at my tune. I wanna say the stumble is because of the injector tables. I ended up bumping some Idle tables.

It was stalling after about 5 seconds, bumped the Airflow parked up to 16 on the 60* IAT mark and I got it to run for around 20 seconds before it stumbled and died.

Note this is a base tune. the Boost VE and timing table has been update since this tune and same with the VE.

I pulled around 4% across the board out of the VE table from this tune as well and im going to try that out. It seems like its getting too much fuel. My Wideband isnt showing anything so I would assume its rich!

Im not getting any codes other than for having no MIL light and Park range sensor

Setup.

2005 5.3L Gen3
LS6 (2004 cam)
Stock heads/bottom end
Flipped manifolds, 2.25 hotside GT45 turbo
Siemens 80lb injectors
TUNED FOR 43.5 BASE FUEL PRESSURE

The current tune consists of.

Basic 3bar OS setup in closed loop
2002 Z06 Fuel and Spark maps.
4l80e trans (currently trans is out and I have a T56 tune in it)

Thanks

Jay

18243

[RADustin]

go back to stock 5.3 VE for 400 and 800 RPMs up to 80kPa.

add air in the air friction table in start up.

then mess with the decay to get it to decay out correct.

I would start by adding a bunch of air- say 400% and work it from there until it starts like you want.

[jay_rich]

I went over my entire SD COS 3bar setup again. I forgot to look this up at the time.

C2906 (Maf Low Freq Fail Limit) I left this at 6 since it wasnt called out in the tutorial. I looked it up and noticed it should be set to 1 and I read I should set C2904 to something like 12000.

Maybe this is possibly another issue. Ill try this out when I get home. I did try pulling fuel from the VE and adding timing down low and i couldnt even get more than just a fire and die out of it.

I pulled #3 plug this morning and it looks a bit over fueled.

Jay

[240sxpooter]

You need to fix the A0001, and A0002 maps

These need to be changed to 50, SAVED, then reopened and changed to 100....

[jay_rich]

Awesome, I was wondering about those. I kept reading the tutorial over and over and was like I dont get why they are out of range. A quick search shows MANY people mess this up. Ill try when I get home. My friend gave me his 3bar tune with 88lb injectors to test also (obviously change the IFR) So that's whats currently in the car but it also shows out of range on my software.

Ill give this a whirl when I get home from work and see if it works!

Jay

[240sxpooter]

Awesome, I was wondering about those. I kept reading the tutorial over and over and was like I dont get why they are out of range. A quick search shows MANY people mess this up. Ill try when I get home. My friend gave me his 3bar tune with 88lb injectors to test also (obviously change the IFR) So that's whats currently in the car but it also shows out of range on my software.

Ill give this a whirl when I get home from work and see if it works!

Jay

Yeah behind the scenes in the raw bin file the numbers are not 100... 100 is the max displayed valve in EFIlive for those parameters. so who knows what it really is, but saving 50 sets it to 50, then changing it to 100 sets the information correctly.

[jay_rich]

18252
18253

well fixed the outta range and it fired but died again. It looks like I see it commanding like 4.0:1 AFR on start up? Went over the parameters and cat figure out what I missed?

[240sxpooter]

18252
18253

well fixed the outta range and it fired but died again. It looks like I see it commanding like 4.0:1 AFR on start up? Went over the parameters and cat figure out what I missed?

Looks like that's just for Cranking so I wouldn't get side tracked on that. Have you tried bumping your idle up to like 1200rpm until the tuning is done? Also can you keep the car running by giving it gas?

[jay_rich]

It wants to die as soon as i open the throttle body. I loaded my friends tune in just scaled the injectors. Im gonna try that today.

Jay

[jay_rich]

Just thought of something. i havent finished putting my trans in. So I havnt hooked up any linkage OR the NEUTRAL SAFETY SWITCH WIRE. Does anyone know if this prevents the pump from suppling fuel after the car has been started. Im almost wondering if the car is firing off the fuel thats in the rail then dying out. Its hard to check the pressure since I have an adjustable regulator that bleeds off as soon as the car is fired. it is a simple fix when I get home. ill just ground the wire for now and see.

Jay

[joecar]

Just thought of something. i havent finished putting my trans in. So I havnt hooked up any linkage OR the NEUTRAL SAFETY SWITCH WIRE. Does anyone know if this prevents the pump from suppling fuel after the car has been started. Im almost wondering if the car is firing off the fuel thats in the rail then dying out. Its hard to check the pressure since I have an adjustable regulator that bleeds off as soon as the car is fired. it is a simple fix when I get home. ill just ground the wire for now and see.

JayNo, it does not stop the fuel pump from running.

Is this what you're seeing, the fuel pump is not running...? When you key-on do you hear the fuel pump prime for 2 seconds...?

To measure FPR/rail pressure, remove the fuel pump relay and jumper the socket (using a fused jumper wire) so the pump runs; then remove the reference hose and measure rail pressure.

[joecar]

Did you try this:


...
Also can you keep the car running by giving it gas?

[jay_rich]

Yes the fuel pump primes on initial key ON and when the PCM is finished tuning.

When i give the car throttle is dies pretty well instantly. I guess next will be hook the neutral switch up then possible jumper the fuel pump.

I was having a hell of a time trying to set the rail pressure since the car was just priming for 2 seconds (filling 8an feed and 6an return).

I will report back later tonight.

Jay

[RADustin]

is the rail holding pressure after it primes?

[jay_rich]

It is not but its expected with the adjustable regulator. They bleed off the fuel. Its the "summit" version or of the aeromotive 13109.

Jay

[jay_rich]

Well didnt do a thing but toss a new tune in it and it fired and ran beautiful. Not sure what i missed on my tune.

Jay

[joecar]

Can you compare the old and new tunes (using the compare feature in the tunetool)...

[jay_rich]

I plan on doing that when I have time this weekend. Its still bothering me what I missed. I basically started with a stock 2002 5.3L file. Did the COS3 and verified everything matched my friends tune for that. VATS/Column Lock was disabled, etc. Unless it was the injector tuning. I did update the voltage offsets to match what i found online.

Left all the parameters stock but updated the Flow rate (10.079) (43.5psi base 1:1 regulator) then the Voltage offset as following.

6V=2.811MS
8V=1.777MS
10V=1.288MS
12V=1.017MS
13V=0.903MS
14V=0.801MS
15V=0.721MS

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