2004 5.3 Exhaust popping/burbling on deleceration

[jeverett]

OK, a question. Why won't the O2 sensors on there adjust the mixture? ISn't that what their on the truck for? I don't really see spending money on something that might be working in the first place.

[BRARUN]

i agree with grollins i build these trucks from frame up so far i've done 14 of them ome thing i have learn from it is that the ecm doesn't know that you put a 40 series on it. it's going think something is wrong then the ECM is going to through settings off. but it's your choice. you either can be slow and loud or loud and fast i would also ask the people who made the exhaust

[Jimmiz71]

After reading this I'm leaving my resonator alone, sounds like i'll have a backpressure problem if im running only my 20 series. Sounds good now ill just go with the assumption Flowmaster gave it to me for a reason...
Thanks for the input,
Jimmy

[jeverett]

Ok, I have another question. You mentioned loud and slow, or loud and fast. How would I make the ECM know that I've made the mods? Replace the 02 sensors?

[Jimmiz71]

I remember Steve asking about the noise I dont think he had a performance problem, if he was running too lean or rich I would think his gas mileage would drop and or he would be running hot, I thought he was just annoyed with the noise... ??

[LoneWolf3]

So all and all, it appears that the vehicle, no matter what the year, needs to be taken to your dealer and re-tuned, and what would they do in this tune up, since they have SFI and no jets to replace, turn, ect? What do they tweak to change fuel delivery.

[desertmike1]

Hey guys let me throw a twist on this thread!

I have a 99 with a 5.3 I baught used accouple years ago from a Buddy of mine, and he installed a flow master (series unkown) but he did say it had a three pass. Any how it burbled and popped ocassionaly and I thought nothing of it.
Recently the truck starting backfireing and loosing power (SES light lit up) so I took it to Chevy, the PCM latched two codes that indicated left and right banks lean, any how the final prognose's was low fuel pressure at 25psi.

A new fuel pump and filter "$883" later the truck runs absalutely BITCHEN with 57psi fuel pressure, and NO BURBLE or POP in the exhaust anymore, in fact my 15-16 MPG is now 16-17 MPG back and forth to work, I seriously beleave my fuel pump was crap from day 1

Sorry about the long post!

-Mike

[grollins]

Originally Posted by LoneWolf3

So all and all, it appears that the vehicle, no matter what the year, needs to be taken to your dealer and re-tuned, and what would they do in this tune up, since they have SFI and no jets to replace, turn, ect? What do they tweak to change fuel delivery.

Wolf,
The fuel pulses, as well as sensor readings are changed. It is done AFTER the factory ECM with an aftermarket tuner. It kind of lies to the ECM, and lets it believe everything is stock and all is well. That's all the ECM knows anyway. Then the pulses and sensor readings are changed into and out of the ECM. Go here and read up. It's about $300, but smoothes things out and you won't cook exhaust valves and gum the races with burnt oil:

http://www.jetchip.com/

Click on Domestics and select your truck. You would want stage 2.

Here is a good example of a ECM lier for your scooter:

http://www.powercommander.com/

They made what's in my 2000 Road King. It can be custom tuned with a PC. The bigshot wrenches at the Harley shop said it runs "like a raped ape", and were shocked it's an aftermarket tuner and my PC that did it.
2" drag pipes, moded baffles, open air cleaner. Not a speck of blue pipes, and YES you CAN be loud AND fast!

Good luck Bro!

[LoneWolf3]

Thanks, I'll look at the chip site, I kow about the power commander, but never went with it, you know so many people have and some don't and when you hang around the shop they go back and forth on ups and down of the power commander, so I just said, well, softtail was runnin fine, I never got it.....Thanks I'll look into chip site.

[LoneWolf3]

I looked at the chip site, you were talking about that PCM, I don't see one for my year though, it's that small barrel shape chip?

[huminski]

Yeah I definitely have no complaints about power, I was just getting annoyed at the noise. It's not that bad under normal driving, it was just that when I pull a trailer with 6 atv's on it, I was downshifting to assist with braking when approaching tolls and lights and it was very pronounced then. I'll live with it.

[grollins]

Originally Posted by LoneWolf3

I looked at the chip site, you were talking about that PCM, I don't see one for my year though, it's that small barrel shape chip?

Here is the part number:
Stage 2 #20310s
$319.95

[LoneWolf3]

Actually I would use the stage one since I don't have any serious mods, the techs at the site told me stage 1 as well, but I'm not having any issues, shiftings are fine, mileage is good, I'll hold off for now, thanks.

[silveradoman]

I was towning way more than I should´ve on a mountain road with a stock exhaust on a 94 C/K truck, downhill no Second gear it gurgled and popper like crazy, on my current 2000 silverado we busted the stock muffler one time when I took a shortcut through the river bed (jejeje) and on the trip back (yes I almost caused an avalanche with the noise) it gurgled like crazy, and that didn´t happen while the stock muffler was attached to the truck.

[jeverett]

I think I'm switching to Magnaflow....