5.3 falls on its face

pholmann · Oct 16, 2015

I would agree that the new cam and lack of tune is the problem.

croes · Oct 16, 2015

pholmann said:
I would agree that the new cam and lack of tune is the problem.

I ran my ls1 with a zo6 cam on my 5.3 tune around a little before I had it tuned, I wasn't doing WOT pulls or anything but it ran decent.

pholmann · Oct 16, 2015

I know Travis Vance out a cam in his buggy and it fell on its face until he had it tuned. I think it depends on how much cam you put in. Also changes in things like intake centerline, lobe separation, etc

muddinmetal · Oct 16, 2015

I wish you would have stuck with a Toyota :****:

croes · Oct 16, 2015

pholmann said:
I know Travis Vance out a cam in his buggy and it fell on its face until he had it tuned. I think it depends on how much cam you put in. Also changes in things like intake centerline, lobe separation, etc

True, I'm just leaning towards the fact that you can't get too ridiculous with a cam on a stock 5.3. It definitely needs to be tuned.

Whats the story on this 5.3, was it running before? Is the tune stock?

hjpcummins · Oct 16, 2015

216/220 114 cam
So I dropped by amigozone and picked up a few things
Fuel pressure gauge. ( 54 to 58 psi idel jump over 60 at wot)
Obd scanner and compression test tool

Before I started it today I scanned codes
Came back with
P0650 (lamp malfunction CEL)
P0122 (Throtle pos.sensor, could this possiably be tuned for dbw?)
P0500 (vss, why would it pull this code If it's tuned for mech. Trans?)

Cleared the codes out and drove it around the yard. Still not running right but a tad better.

Scanned codes again and p0650 came back in but not p0122 ?
Odd?

Fuel pressure looks good steady 54 psi. Disonnected 02 sensors and started to run worse.
I was able to read 02 readings and they were exactly the same, but not sure if this is what they should look like?

Here are some pics of logged info

hjpcummins · Oct 16, 2015

Re: Re: 5.3 falls on its face

croes said:
True, I'm just leaning towards the fact that you can't get too ridiculous with a cam on a stock 5.3. It definitely needs to be tuned.

Whats the story on this 5.3, was it running before? Is the tune stock?

Motor was spose to be in running condition blah blah blah new cam amd springs blah. Pulled the pan off and looked like chit (look on my profile for thread and pics)

Short story long I rebuild this pos. And at lease it did have new springs and cam.

I know the motor won't run 100% with out tune but would it run this damn bad without it

pholmann · Oct 16, 2015

Check out those fuel trims. The long term is high. What the hell is going on with your short terms. Those are way off base man.

grcthird · Oct 16, 2015

It is limp mode, it will not run worth a **** until you take care of the throttle code.

hjpcummins · Oct 17, 2015

Re:

Swapped TPS runs alot better. Idel is low but may be the cam? Still pretty sluggish driving.

ALLJ · Oct 17, 2015

I think you will continue to have problems until you get it tuned IMO it will save you a lot of trouble and time chasing problems a good tune will take 2-3 hrs to get it dialed in hope you get it worked out

grcthird · Oct 17, 2015

Good deal, get it tuned and :driving:

hjpcummins · Oct 18, 2015

And Im pretty much done taking educated guess , spoke with a local speed shop to just look into it. But a this point I just want it 100% ready to ride!

hjpcummins · Oct 18, 2015

Re:

Got around to fooling with this thing tonight, completed a compression test (all cylinders test between 155-160 with three revolutions) leak down was 2-4 psi after 10 seconds) from a quick Google search these a good numbers. One thing I did notice was carbon buildup and 2 plugs had what seem to be gas. What should I be looking for on a fresh build?

croes · Oct 19, 2015

Re: Re: 5.3 falls on its face

hjpcummins said:
Motor was spose to be in running condition blah blah blah new cam amd springs blah. Pulled the pan off and looked like chit (look on my profile for thread and pics)

Short story long I rebuild this pos. And at lease it did have new springs and cam.

I know the motor won't run 100% with out tune but would it run this damn bad without it

I'm wondering if you have injector issues, in the short term trims you posted its adding a lot of fuel to one bank and pulling a lot from another???

pholmann · Oct 19, 2015

Re: Re: 5.3 falls on its face

croes said:
I'm wondering if you have injector issues, in the short term trims you posted its adding a lot of fuel to one bank and pulling a lot from another???

That's what I was noticing. Also could have an O2 issue.

Neal3000 · Oct 19, 2015

Vengence Racing up in Cumming has a really good tuner

bjeep · Oct 19, 2015

Neal3000 said:
Vengence Racing up in Cumming has a really good tuner

Have you used them/him?

hjpcummins · Oct 19, 2015

Re: Re: 5.3 falls on its face

bjeep said:
Have you used them/him?

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

hjpcummins · Oct 19, 2015

Re: Re: Re: 5.3 falls on its face

croes said:
I'm wondering if you have injector issues, in the short term trims you posted its adding a lot of fuel to one bank and pulling a lot from another???

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