2004 6.0 NV4500 Tahoe

[Dantheman1540]

is this on cold starts or all starts?

Yes.........

Mostly on cold starts but it doesn't discriminate and will get me on a warm start sometimes too.

 

[Dantheman1540]

I got HPT to read over 6k but I wasn't able to see what the dash was reading at the same time, I guess I need to do a deliberate pull to 6,800 dash read out and compare it to the HPT log.

@randeez I sent you two new log files, one is a cold start idle warm-up with no accessories on and the other is my ride home with a couple of high rpm pulls in second gear.

 

[Dantheman1540]

Huh one thing I just noticed is that I didn't have the BIAF In gear and P/N the same. I'm fairly certain in the past I had them the same but I guess not anymore. I'd assume the truck looks at the P/N row since it doesn't know it's in gear so I will copy them over. If I have been changing the wrong thing I'm gonna feel pretty dumb

 

[George B]

Huh one thing I just noticed is that I didn't have the BIAF In gear and P/N the same. I'm fairly certain in the past I had them the same but I guess not anymore. I'd assume the truck looks at the P/N row since it doesn't know it's in gear so I will copy them over. If I have been changing the wrong thing I'm gonna feel pretty dumb

A simple and overlooked fix is always welcome.

 

[randeez]

I got HPT to read over 6k but I wasn't able to see what the dash was reading at the same time, I guess I need to do a deliberate pull to 6,800 dash read out and compare it to the HPT log.

@randeez I sent you two new log files, one is a cold start idle warm-up with no accessories on and the other is my ride home with a couple of high rpm pulls in second gear.

it looks like it cold starts fine lol
the misfires look bad though, you make sure theyre all plugged in n stuff? wires pretty new? whenthe last time you checked plugs

 

[Dantheman1540]

A simple and overlooked fix is always welcome.

If it fixes anything lol.

it looks like it cold starts fine lol
the misfires look bad though, you make sure theyre all plugged in n stuff? wires pretty new? whenthe last time you checked plugs

the misfires make no sense to me I don't not feel anything every and the plugs looked great 2 months ago. The wires are kinda mismatched junk but I inspected them when I checked out the plugs and nothing looked bad, I did not OHm them out tho.

The cold start is steady but why does it start and initially idle at 16-18afr? The commanded is clearly 14.7 and eventually, it gets down to that but the first few minutes it's super lean and if I start driving during that period it usually swings even leaner I've seen 20s or it dives down crazy stupid rich like 9.

Maybe all this is related to some strange ignition issue like a bad coil pack causing misfires which throws everything else off? Maybe I need to nut up and buy some decent plug wires for once.

 

[pwtr02ss]

If it fixes anything lol.


the misfires make no sense to me I don't not feel anything every and the plugs looked great 2 months ago. The wires are kinda mismatched junk but I inspected them when I checked out the plugs and nothing looked bad, I did not OHm them out tho.

The cold start is steady but why does it start and initially idle at 16-18afr? The commanded is clearly 14.7 and eventually, it gets down to that but the first few minutes it's super lean and if I start driving during that period it usually swings even leaner I've seen 20s or it dives down crazy stupid rich like 9.

Maybe all this is related to some strange ignition issue like a bad coil pack causing misfires which throws everything else off? Maybe I need to nut up and buy some decent plug wires for once.

I've had the best luck with OEM wires. The "original equipment" type. I had 2 sets of MSD wires on my camaro and they would randomly misfire. Real treat when the engine is fresh and you're chasing your tail...

 

[randeez]

if youre using pump gas (E10) set the stoich to 14.10840 under fuel>general>stoichiometry

it starts (the first couple seconds) rich. you can stretch out the table under fuel>open loop/base>eq ratio over 68* its calling for 1.0 eq (no adder) when you start it over that temp it wants to dump right into 1.0eq. maybe stretch some adder to 100*+

 

[randeez]

If it fixes anything lol.


the misfires make no sense to me I don't not feel anything every and the plugs looked great 2 months ago. The wires are kinda mismatched junk but I inspected them when I checked out the plugs and nothing looked bad, I did not OHm them out tho.

The cold start is steady but why does it start and initially idle at 16-18afr? The commanded is clearly 14.7 and eventually, it gets down to that but the first few minutes it's super lean and if I start driving during that period it usually swings even leaner I've seen 20s or it dives down crazy stupid rich like 9.

Maybe all this is related to some strange ignition issue like a bad coil pack causing misfires which throws everything else off? Maybe I need to nut up and buy some decent plug wires for once.

mine would misfire with the maf connected... soon as i ditched it all the misfires when away. i have absolutely no clue why

 

[Dantheman1540]

I've had the best luck with OEM wires. The "original equipment" type. I had 2 sets of MSD wires on my camaro and they would randomly misfire. Real treat when the engine is fresh and you're chasing your tail...

Yeah, I have like 3 MSD wires, maybe 2 OEMs, and then 3 random other brands that are red but not MSD. It's kinda a cluster but I have a huge pile of wires and can't stand not using stuff I already have.

I'm gonna get those $130 ceramic boot short ones next go aroud, maybe they will stay together.

if youre using pump gas (E10) set the stoich to 14.10840 under fuel>general>stoichiometry

it starts (the first couple seconds) rich. you can stretch out the table under fuel>open loop/base>eq ratio over 68* its calling for 1.0 eq (no adder) when you start it over that temp it wants to dump right into 1.0eq. maybe stretch some adder to 100*+

Stoich is now set to 14.1 what do you mean stretch the table out? You mean ad some gradually going up in temp so at 68* maybe make that 1.03? or subtract some making it .97?

mine would misfire with the maf connected... soon as i ditched it all the misfires when away. i have absolutely no clue why

I remember you posting about that, mine does it maf or no maf unfortunantly