New to tuning and want to drive my truck

[McMx5]

Ok so bare with me when I try to learn this. Did an ls swap & used an 02 5.3 dbc. Installed a btr stage 3 truck cam 218/224 .553/.553 110lsa. 2800 stall, long tubes, 3in dual exhaust. I spent a week after the install waiting on a response from several tuners in my area who never got back with me. So ordered the mpvi3 & figured id do it myself. Waited a week for that but did not realize I would need a wideband (for best results) but my wideband wont be here for another week. I spent all night reading up on tuning but im lost. I just want to drive my truck. Im just looking to cruise, not race, and ive been reading this can be done without a wideband. It runs now but seems extremely rich. Occasionally starts to misfire. Can someone point me in the right direction? Much appreciated


02 5.3 swap short drive.hpl

[blindsquirrel]

Where is the tune file that it was running during that log? The log is just the output, if the log shows it's rich maybe it's being told to do that in the tune file.

What are the basics here? What fuel system. What fuel pressure. What type pressure regulator. Injectors and everything same as the donor vehicle?

[McMx5]

just added the tune file. Its a stock tune. Stock fuel system from 96 Chevy truck. ~52psi fuel pressure. Regulator & injectors are original from the 5.3

[blindsquirrel]

In your log the B2 O2 sensor is really lazy, it never starts switching. Both sensors should 'wake up' within less than a minute, much less, even from a dead cold start. You can't tune based off fuel trims until you have two good healthy upstream O2 sensors.

If you changed anything at all about the intake tube shape, length, number or location of bends, or size you'll have to retune the MAF.

2002 LM7 should have a base pressure of 58psi:

385-425 kPa (55-62 psi) VIN: (V, T, U)

335-375 kPa (48-54 psi) VIN: Z

If your 52psi is with the vacuum hose disconnected from the regulator, or at key on engine off, you probably have a L59 regulator instead of the correct LM7 reg. If you checked it running with the hose still connected, you need to recheck again with the hose off.

[McMx5]

Installed new o2s. Fuel pressure is 55psi. Here are the results. Where should I start to try to dial this in?

[blindsquirrel]

If you're really asking where to start, I'd say probably pick one of the (reputable? popular?) Youtube channels. Make sure anything you follow fits your hardware - like, an idle tuning guide for DBW doesn't work so hot for DBC or vice versa. You'd be surprised how many Gen 3 guys post here asking why they can't find the VVE table (Gen 4 stuff) some video they're trying to follow was showing.

O2s look... better, but still aren't doing normal switching behavior.

[McMx5]

Yeah youre probably right. I feel like ive watched a million videos & read forums but when Im still lost. I appreciate the responses. This is my 1st time trying to tune so I have a lot of learning to do before I get it right

[C6_Will]

Look up Drive By Cable idle tuning. There are a few good write ups out there that can explain a lot better than I could in a quick response on here. Definitely need to get the O2's acting right though.