No start, has fuel and spark

[Turbo6Justin]

First swap but pretty basic, 2002 5.3 turbo cam, stock heads, 7675 turbo, 1500cc snakeeater injectors, 4l80e. To start with the tune I downloaded the stock 2002 truck file, ran it through the 3 bar operating system change, did the 4l80e segment swap and then grabbed dam near every table fuel and spark related from a tune done with these injectors figuring it would get me at least started and running. But no dice it will kind of try to start but no amount of cranking will get it to catch.

The wideband shows 10.0 when cranking and it smells very fuel rich. Checked and it is getting spark to the plugs. It seams strange to me that it isn't even trying to backfire through the intake or exhaust. Map sensor is flat style but was in a working vehicle before, but I am kind of miffed at the log readings and when I put compressed air to the sensor it doesn't register boost but if I suck on it will read 1.5-2.5 manifold psi vacuum. I did remove the old map pid and added the new 3 bar pid to the scanner. One other weird thing is the stock truck tune and the tune I am grabbing all the information from (from the sloppy files specific for the 1500 injectors) has the firing order different. It is in the same order but starts with a different cylinder. I have tried it both ways and it doesn't really make any difference.

Can someone take a look at the log or the tune and see if anything jumps out?



crank no start.hpl
stock 2002 lm7 3 bar with sep1500s 4l80e performance trans tune idle fuel spark torque firing or.hpt

[DrLoch]

Are you trying to run in SD mode? If so you don't have it set up correctly, DTC's, Base Idle is filled in, rolling idle has all zero's, MAF @ 60 across the board, Injector bank has zero's for all injectors. Those are the quick look observations. MAP looks like it did move at one point.

[Turbo6Justin]

Yes I am trying to run SD no Mass air sensor to speak of. I did the 3 bar SD operating system thing, verified by the addition of the power enrichment tables. The tune I was taking the injector information from and eventually took almost everything else from was from a sloppy file database listed as 3bar SEP 1500's (my injectors).

[Turbo6Justin]

Okay This one is on me. Read on to have a good laugh. I have tuned another vehicle with an AEM system and with that as I make changes they are sent into the ECM, live tuning as it were. So I was going through and making tons of changes and never went to "write vehicle". I suppose it would have helped to actually send the new information to the ECM. The general tuning I am pretty decent with, the HPtuners interface and the GM ECM will take a little getting used to. If we can't laugh at ourselves who can we laugh at?


Turned the key and it started, horrible surging idle but it started.

[DrLoch]

Stuff happens.. Post a correct file if you get a chance.

[Turbo6Justin]

idle likes to creep up.hpl

stock 2002 lm7 3 bar with sep1500s 4l80e fing with idle just guesses really.hpt

Here is about the most recent log and Tune. I need to step away and come up with a game plan on the idle, do some reading etc. I am still concerned with the MAP values do they seam right? The main problem it has is idle surging, which is a little better than before and a runaway idle. It will start and idle at 1000ish then creep up a little, give a little stab of the pedal to 'reset' it and it holds on to that new 3-400 rpm higher level until I eventually shut it off. This is a drive by cable set-up with an IAC. It is also idling at like 14.8-15.5 AFR on the wideband which seams way lean for something like this, my other car gets all pissed off idling anything leaner than 13.9 or so. Then again this probably explains the idle surging.

Thanks for the help so far!

[5FDP]

Can't view the tune on this computer but you'll want to disable closed loop so it stops the fuel trims from going bat shit crazy trying to fix the airflow model. Disabling both closed loop and fuel trim will be helpful, also make sure the open loop EQ ratio is set to 1.00 so it only tries to run at stoich above like 140 degree coolant temps. You can enable closed loop way later on if you want. For now you'll be using a wideband and wideband error to fix the VE table.

LS engines run great at stoich (14.68) when the airflow model is correct and you aren't trying to be all sassy with the idle timing to make it chop hard.

With the stock computer don't get too much into idle tuning without working the VE table over from idle to part throttle. It can throw you further off if the fueling is all over the place.

[lukearmstrong1990]

MAF isn't failed correctly and the VE table is all kinds of wrong.

what fuel?
what MAP sensor?
what injectors?
dead head or return style fuel system?
what's your barometric pressure?

[Turbo6Justin]

Fuel is E50-60 right now, will be e85.
I am using the GM Map Sensor part number 12223861
The injectors are Snakeater 1500cc's
Return style fuel rail
baro is 29.9 in mg or there abouts

Care to point me in the correct direction VE wise??

What else do I need to do to get rid of the MAF, again, it is not in the car.

Thanks


Here is the latest log, still real lean and idle likes to ramp up. not a lot changed in the tune it does idle better.
stock 2002 lm7 3 bar with sep1500s 4l80e open loop st lt fuel trims off torque management off id.hpt
ran well idle still crept up.hpl

[1364838952]

It looks like your VE Table is inverted somehow. I've never seen anything like that before. Look at your STFT in the log.. It's telling you that you are WAAAAAYYYYYY lean! I would go back to a stock, or stock-ish VE table and start over. Do you have a W/B O2 sensor? If so, get it integrated into HPT and use it to tune your VE table before you do anything else. DO NOT attempt to drive the vehicle. Those values in your table could potentially damage your engine.

[DrLoch]

Your gonna hurt that thing if you try and drive it. Look here for info about failing the MAF https://forum.hptuners.com/showthrea...F-not-failing) As advised you your VE table is wacked, Where is your IAT sensor? if it's part of your card MAF you need to leave it connected.

HOOK UP YOUR WB and include it in your log.

[Turbo6Justin]

I will grab another log here in a few minutes, I got the wideband sorted out yesterday, it was there all along but I just figured out how to get the Scanner to see it through the EGR. I am not going to drive it anywhere, it doesn't even have a torque converter right now so that isn't even an option. The IAT is in the intake just behind the throttle body, it is a GM sensor from a 90's 3800 motor.

Things I have changed but did no good, it is calling for an idle of like 700 which is too low but when I change it higher to like 950ish it starts and stalls right away, that is weird to me. I changed the PCV system back to stock with a PVC valve in the drivers valve cover and the other hose from the passenger valve cover to the throttle body. That seemed to help the WB reading a little, I suspect I was getting 'unmetered' air in somehow.

And lastly about the VE table, I took the entire ve table from a 5.3 turbo running 127lb injectors, what is in there right now is none of my doing but I figured it would get me close, then I hear words like inverted and WAAAAAAAAAAAy off and I wonder how a running tune could be that bad. Anyone have a good VE table 3bar, turbo, 5.3 stock head small ljms stage 2 turbo cam with big injectors?

I am going to go out an try to fail out the MAF and get another log right now.

Here is the thing, the WB says its terribly lean, the stock o2s say its lean but this is not lean, it can't be after 2 minutes it is eye watering can't breath clothes stink for hours rich.

stock 2002 lm7 3 bar with sep1500s 4l80e open loop st lt fuel trims off torque management maf fa.hpt

maf failed i think.hpl

[Rosadosvt]

any updates on this issue Justin?

[JordanM]

I will grab another log here in a few minutes, I got the wideband sorted out yesterday, it was there all along but I just figured out how to get the Scanner to see it through the EGR. I am not going to drive it anywhere, it doesn't even have a torque converter right now so that isn't even an option. The IAT is in the intake just behind the throttle body, it is a GM sensor from a 90's 3800 motor.

Things I have changed but did no good, it is calling for an idle of like 700 which is too low but when I change it higher to like 950ish it starts and stalls right away, that is weird to me. I changed the PCV system back to stock with a PVC valve in the drivers valve cover and the other hose from the passenger valve cover to the throttle body. That seemed to help the WB reading a little, I suspect I was getting 'unmetered' air in somehow.

And lastly about the VE table, I took the entire ve table from a 5.3 turbo running 127lb injectors, what is in there right now is none of my doing but I figured it would get me close, then I hear words like inverted and WAAAAAAAAAAAy off and I wonder how a running tune could be that bad. Anyone have a good VE table 3bar, turbo, 5.3 stock head small ljms stage 2 turbo cam with big injectors?

I am going to go out an try to fail out the MAF and get another log right now.

is the thing, the WB says its terribly lean, the stock o2s say its lean but this is not lean, it can't be after 2 minutes it is eye watering can't breath clothes stink for hours rich.

stock 2002 lm7 3 bar with sep1500s 4l80e open loop st lt fuel trims off torque management maf fa.hpt

maf failed i think.hpl

Thanks indeed!