5.3 falls on its face

croes · Oct 20, 2015

Re: Re: Re: 5.3 falls on its face

hjpcummins said:
Would you mind breaking that down to me, as fast as what am I exactly looking at on scanner and so on

Where it says "ST FTRM1 (%)" and "ST FTRM2 (%)". Bank 1 is the drivers side, and bank 2 is the passenger side.

A positive number means its adding fuel (lean condition) to try to achieve what the pcm is calling for in regards to AFR, and a negative number means it is pulling fuel (rich condition) to achieve the desired AFR. Closer to 0 the better.

So the drivers side bank is very lean as its adding a lot of fuel, and the passenger side is rich as its pulling a lot of fuel. Hold the rpms around 2000-2500 and see if the numbers stay the same.

The reason I don't think its o2's is because when you unhook them it runs worse, because its losing its live data in regards to actual AFR and running off the tables.

pholmann · Oct 20, 2015

A healthy and normal fuel trim should be in the low teens.

FlatlandFSJ · Oct 20, 2015

Would it be dumping more fuel to compensate for a clogged injector/line? And what would normally cause it to pull a buncha fuel out? other then it trying to get the air/fuel it wants.

Just tryin to prepare myself for a LS eventually.

croes · Oct 20, 2015

FlatlandFSJ said:
Would it be dumping more fuel to compensate for a clogged injector/line? And what would normally cause it to pull a buncha fuel out? other then it trying to get the air/fuel it wants.

Just tryin to prepare myself for a LS eventually.

That's what I'm thinking, things like the MAP and MAF affect it too, but since its polar opposites bank 1 to bank 2 I don't think they are bad. Other things like exhaust setup and o2 placement can affect it as well. Now he could have a bad o2 sensor which is throwing one bank off with them hooked up and plugged injectors on one bank, hard to tell. Guess he could swap o2's side to side and see if it stays the same or follows the swap.

pholmann said:
A healthy and normal fuel trim should be in the low teens.

Yep, my short term trims stay around 0-10 at idle and pull towards 0 when I'm on it.

Neal3000 · Oct 20, 2015

Re: Re: 5.3 falls on its face

hjpcummins said:
Vengeance is good real good prices too.. they are more of a high end shop. But their work reflects that. I'm currently speaking with moes speed shop in dallas ga, anybody was experiance with them

They will work on anything with an LS in it, my boy Kevin had his buggy tuned there, they did a great job on it, and free tunes for one year afterwards. Think it was about $300

hjpcummins · Oct 20, 2015

Re:

Really? Dyno or just re flash tune?

hjpcummins · Oct 20, 2015

Re: Re: Re: Re: 5.3 falls on its face

croes said:
Where it says "ST FTRM1 (%)" and "ST FTRM2 (%)". Bank 1 is the drivers side, and bank 2 is the passenger side.

A positive number means its adding fuel (lean condition) to try to achieve what the pcm is calling for in regards to AFR, and a negative number means it is pulling fuel (rich condition) to achieve the desired AFR. Closer to 0 the better.

So the drivers side bank is very lean as its adding a lot of fuel, and the passenger side is rich as its pulling a lot of fuel. Hold the rpms around 2000-2500 and see if the numbers stay the same.

The reason I don't think its o2's is because when you unhook them it runs worse, because its losing its live data in regards to actual AFR and running off the tables.

Thanks I'll try that, I'll report back.

Neal3000 · Oct 20, 2015

Not on the dyno, the tuner just rode with him and tuned it from the passenger seat

croes · Oct 20, 2015

Around here we have two guys, one is an EFI Live developer with unlimited credits (due to tune quantity) and a drive tune is $75 for Gen III and $150 for newer stuff mostly Gen IV. The other guy with an in ground dynojet is $150. A dyno tune is usually around $300ish. Both of these tuners are VERY competent, the one with the dynojet's personal car puts 1100+ to the ground with a procharged LSX 427. :smoke:

hjpcummins · Oct 20, 2015

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What's your location? Just weighing my options on a tuner.

croes · Oct 20, 2015

Re:

hjpcummins said:
What's your location? Just weighing my options on a tuner.

Syracuse, IN 46567

ALLJ · Oct 20, 2015

Ive got to ask ! Why would there need to be touch up tunes done if nothing has been changed on the engine or related components ? never heard of this needing to be done once its dialed in im not saying its not needed just curious. My 6.0 has not been touched in 4 years since it was tuned on dyno

hjpcummins · Oct 20, 2015

Re:

Well the lil engine that could...DID.

Iv been scratching my head bald over this ****... and Iv be interested is what was mentioned about the o2 readings. So I pulled the plug. Again. And noticed lite carbon build up. Cleaned them off and just started checking over conections. Then it hit me, I remembered when installed the harness I taped up the the excess wireloom for the 02s. Maybe just maybe I have them crossed. Pulled tape off and sure enough they DaMN! Sure were! And in the back of my head I'm thinking this couldn't cause it to run this damn bad..surly not. Cranked the bitch up noticed it was idling better.

So fawk it letd pull this thing out on the road and see if it continues to disappoint me. Started cruising and noticed how great it was running..so I layed into It

Since then iv had a damn smile on my face. This thing damn GOs. (Keep in consideration I'm use to a 22r) it blew my mind how tq'y this thing is.

hjpcummins · Oct 20, 2015

croes · Oct 21, 2015

Re:

hjpcummins said:
Well the lil engine that could...DID.

Iv been scratching my head bald over this ****... and Iv be interested is what was mentioned about the o2 readings. So I pulled the plug. Again. And noticed lite carbon build up. Cleaned them off and just started checking over conections. Then it hit me, I remembered when installed the harness I taped up the the excess wireloom for the 02s. Maybe just maybe I have them crossed. Pulled tape off and sure enough they DaMN! Sure were! And in the back of my head I'm thinking this couldn't cause it to run this damn bad..surly not. Cranked the bitch up noticed it was idling better.

So fawk it letd pull this thing out on the road and see if it continues to disappoint me. Started cruising and noticed how great it was running..so I layed into It

Since then iv had a damn smile on my face. This thing damn GOs. (Keep in consideration I'm use to a 22r) it blew my mind how tq'y this thing is.

So bank 1 o2 was reading bank2 and vice versa!? Hell yeah, glad to hear its running better, those short term trims look great!

altfuel1991 · Oct 21, 2015

I would suggest that you clear out the fuel trims in the ecm and let the engine relearn . The high LTFT numbers will make the ecm try to add fuel and at the same time take it away to balance the fuel mixture. This makes the mixture swing wide from rich to lean until it is driven long enough to re-calibrate and dial itself in. This process can take 50 miles or more.

grcthird · Oct 21, 2015

X2 on what Gamel said, you will need a more capable scan tool to do it. Glad you figured it out.

hjpcummins · Oct 21, 2015

Re:

Thanks everybody for the help now it's time to fix my tranny leak!

croes · Oct 22, 2015

grcthird said:
X2 on what Gamel said, you will need a more capable scan tool to do it. Glad you figured it out.

Unhook the battery for 10 minutes and then let it re-learn...

altfuel1991 · Oct 22, 2015

On an OBDII system, if you do not have access to a scan tool that can clear fuel trims can clear it another way. You have to disconnect the negative battery cable from the battery and touch it to the positive cable for about 10 seconds to clear out the learned memory. Just disconnecting the battery will not clear it out.