I somehow, someway came up with the hypothesis that my coil or some component within the ignition system was not performing under load. This was my best guess at this point because I was confident in...

thank you for sharing this with me. I would never of known this and just assumed that my spark advance was haywire according to my data log. Tomorrow I am installing a new distributor with new...

no converter

My ECM is factory..what does this mean? I am still in the initial learning the ins and outs of tuner pro.. isn’t zig zag spark graph not accurate on my log?

I watched the log of the good running 5.7 from the previous post (thank you). I see that your spark advance numbers are fairly consistent. On my log, I see spark advance numbers running up and down...

I had to take a few days off the truck because it was fucking with my mojo. Again thanks to everyody for their assistance. I did another log today of me sitting in my driveway idling and revving...

Thank you Dave W. I appreciate that help so much.! -Tyree

Does anybody have a data log from a known good running 5.7? I would like to compare and contrast against my own data log..Thanks

MOC, I appreciate this reply.. my tank is an aftermarket under bed tank.. brand new from LMC truck. It only has an inlet for for fuel pump supply through sender and a single return line.. at this...

When I first started having these symptoms, they were minor and intermittent. At that time I believed it was a fuel issue. I replaced the fuel sender and also changed to a new high flow fuel...

Does anybody have a known log of a good running factory TBI 5.7 engine. I want to try and compare and contrast against my own log to see if I can learn something.
Thanks again to anybody on this...

I am confident that nothing is mechanically wrong. I again tested my fuel pressure and it is a consistent 12 psi and I also removed my new in line filter to quadruple check that fuel was not being...

When installing the donor harness, I had to lengthen a few wires.. i soldered the necessary joint and properly shrink tubed all of the connections. In addition, I rewrapped everything in a new loom....

Thank to all for thier replies.. I will continue looking for a solution. Truck is at shop and waiting to hear their opinion.? When I get it back, if they can’t find the phantom problem, I will do...

I installed a brand ne filter as well.. I was hoping it would be something simple but it is turning out to be a phantom

Two years and 5500miles on new engine

I used a new distributor, cap, rotor, new wires, and plugs. Originally thought it was low fuel issue...new gas tank and fuel
Sender as well.. I installed new high flow fuel pump with new relay and...

I put did a TBI conversion on a crate motor and put it in my 72c10.. it was running great for about a year and then starting to have phantom intermittent problems during acceleration. Went through...

I decided to swap out egr valve with another one I had laying around. I ran the engine again and it ran much better. I will have to test drive and keep doing more logs. I revved this one up a few...

Thanks for that log. Does anybody have a log of good running 5.7 from start in open loop until it warms up to idle and closed loop. This is when it starts happening in my truck as soon as it goes...

on that map thing, That was me disconnecting the map sensor for a minute looking around for problems. Thanks for the reply I will check and compare. Phantom problem is repeatable and went from...

I just swapped another o2 sensor. Same result. Any other ideas out there?

Does any body have a .xdl log file of a known good running 5.7 so that I may compare my values in my log against a known good running engine.? That would be a great help. Thanks to all in the forums

Thank for the reply damax, does anybody know what is an expected proper reading from a one wire o2 sensor at idle.? I will check this today.
Thanks Tyree

I dropped this engine in truck and was running fine for about two weeks. I then washed my truck then started it the next day and now it starts to surge at idle up at down. I previously had a...