Problems after Aeromotive fuel system install. Question on tune.
12-11-2011, 08:32 PM
#1
TECH Fanatic
Thread Starter
Problems after Aeromotive fuel system install. Question on tune. Well the problems did not start till I installed the roll cage and fuel system. The engine stumbles when power shifting from 2nd to 3rd and from 3rd to 4th. It will clear up after about a second in that gear. Won't stumble like this when going through a gear from say 2000 to 6000 rpm just during a power shift. The wideband is on the driver side with the #5 cylinder thats low on compression. It reads down to 10:1 afr or just rich when happening then goes back to 13:1 when it clears up. Car made 372 rwhp and 389rwtq when this problem started at the lsfest.
Its a n/a stock longblock ls1 6 speed car.
I have already changed the plugs several times i might add and just changed the plug wires. Changed the PE table a million times, turned off the fuel trims pulled spark out checked to see if the fuel pressure was dropping. Just not 100 percent sure what it is.
Also did a compression test on all cylinders, the number 5 cylinder read low at 140, All the others were pretty close to 170. I pressurized the cylinder with air and am getting alot of air out the dipstick tube. Also tested the cylinder next to it to compare and there is a big difference, it holds the air very very well. Now this could be the problem but i am not sure.
My question is when installing an aftermarket fuel sytem do i have to change anything in the tune? It is not hooked up to the stock power supply, i have the pump ran through the aeromotive fuel pump controller and ran from the battery. Curious if the computer cuts the fuel pump during a shift or something? Just want to explore all angles to make sure i get this figured out.
Its an aeromotive a1000#10 line from tank to pump then #8 to the fuel rails. Have the filters hooked on each side of the pump. Two #6 lines run out the back of each fuel rail to the aeromotive fuel pressure regulator then back to the tank through the stock line.
Next thing to test is the coil packs, then tr4 plug in said cylinder then anti fouling setup to see if that does anything. Also unhooking the vaccum pump. Just don't know what else to do.
Nick
Its a n/a stock longblock ls1 6 speed car.
I have already changed the plugs several times i might add and just changed the plug wires. Changed the PE table a million times, turned off the fuel trims pulled spark out checked to see if the fuel pressure was dropping. Just not 100 percent sure what it is.
Also did a compression test on all cylinders, the number 5 cylinder read low at 140, All the others were pretty close to 170. I pressurized the cylinder with air and am getting alot of air out the dipstick tube. Also tested the cylinder next to it to compare and there is a big difference, it holds the air very very well. Now this could be the problem but i am not sure.
My question is when installing an aftermarket fuel sytem do i have to change anything in the tune? It is not hooked up to the stock power supply, i have the pump ran through the aeromotive fuel pump controller and ran from the battery. Curious if the computer cuts the fuel pump during a shift or something? Just want to explore all angles to make sure i get this figured out.
Its an aeromotive a1000#10 line from tank to pump then #8 to the fuel rails. Have the filters hooked on each side of the pump. Two #6 lines run out the back of each fuel rail to the aeromotive fuel pressure regulator then back to the tank through the stock line.
Next thing to test is the coil packs, then tr4 plug in said cylinder then anti fouling setup to see if that does anything. Also unhooking the vaccum pump. Just don't know what else to do.
Nick
12-12-2011, 08:36 AM
#2
Have you gone over all the wiring? Power shifting could be pulling on a connection that doesn't happen otherwise.
Watch the batt volts on the data logs when you pull the power shift...
Is rpm rising to hit the limiter?
Post a data log so the HPT guys can take a look.
Watch the batt volts on the data logs when you pull the power shift...
Is rpm rising to hit the limiter?
Post a data log so the HPT guys can take a look.
12-12-2011, 02:40 PM
#4
TECH Fanatic
Thread Starter
I have checked the battery voltage when logging and it is fine, i raised the limiter to check that out, did not help. I have not checked all wiring yet but have basically looked over most of it, i need to check some stuff around the steering column to be sure. I will post a data log soon man, good idea.
12-12-2011, 02:43 PM
#5
TECH Fanatic
Thread Starter
I think that cylinder is either not firing cause of oil vapor or fouling out or something and i wanted to try a hotter plug in just that cylinder to see if it does anything. Also gonna get one of those antifouling peices that brings the plug out of the cylinder and see what that does. Basically want to try everything to see if it helps any.
12-12-2011, 02:56 PM
#6
If you have a leakage issue on that one cyl, all the extra running on it will do it no good. The best thing to do is a tear down of at least that cyl.
It may not be causing your issues yet, but it very well could in the future.
To answer your previous questions, when the afr goes 10:1 that would not mean your fuel pump is cut as you put. It goes rich. Does your spark drop out? If so there is a table in your computer for that that you can see with HPT. But you would need to graph that. Sometimes it has to do with your WOT fueling as well, such as your PE eq ratio when the rpms go down between shifting or not.
Post up that log and it will tell what you are doing there.
It may not be causing your issues yet, but it very well could in the future.
To answer your previous questions, when the afr goes 10:1 that would not mean your fuel pump is cut as you put. It goes rich. Does your spark drop out? If so there is a table in your computer for that that you can see with HPT. But you would need to graph that. Sometimes it has to do with your WOT fueling as well, such as your PE eq ratio when the rpms go down between shifting or not.
Post up that log and it will tell what you are doing there.
12-12-2011, 02:59 PM
#7
TECH Fanatic
Thread Starter
12-03-2011 for run 4 after the 12.39 run.hpt
12-10-2011 run 1 11.97 at 115 cutting out at start of third and 4th.hpl
12-10-2011 run 2 12.07 at 113.hpl
The sudden drop in voltage for the 02 sensor for bank 2 is something that started when i added all the additional stuff to test for.
Don't mind the VE table having the same number going straight up, just something i tried in case in was going to a different section in the table.
12-10-2011 run 1 11.97 at 115 cutting out at start of third and 4th.hpl
12-10-2011 run 2 12.07 at 113.hpl
The sudden drop in voltage for the 02 sensor for bank 2 is something that started when i added all the additional stuff to test for.
Don't mind the VE table having the same number going straight up, just something i tried in case in was going to a different section in the table.
Trending Topics
12-12-2011, 03:05 PM
#8
TECH Fanatic
Thread Starter
If you have a leakage issue on that one cyl, all the extra running on it will do it no good. The best thing to do is a tear down of at least that cyl.
It may not be causing your issues yet, but it very well could in the future.
To answer your previous questions, when the afr goes 10:1 that would not mean your fuel pump is cut as you put. It goes rich. Does your spark drop out? If so there is a table in your computer for that that you can see with HPT. But you would need to graph that. Sometimes it has to do with your WOT fueling as well, such as your PE eq ratio when the rpms go down between shifting or not.
Post up that log and it will tell what you are doing there.
It may not be causing your issues yet, but it very well could in the future.
To answer your previous questions, when the afr goes 10:1 that would not mean your fuel pump is cut as you put. It goes rich. Does your spark drop out? If so there is a table in your computer for that that you can see with HPT. But you would need to graph that. Sometimes it has to do with your WOT fueling as well, such as your PE eq ratio when the rpms go down between shifting or not.
Post up that log and it will tell what you are doing there.
12-12-2011, 05:38 PM
#9
I have a feeling you are shooting yourself in the foot right now with the extreme you are going to. Stop chasing your tail. Let do first things first and go from there.
Your fuel trims look like crap. They max out immediately then come back in then back out. How does this thing run like that lol. Esp at such an rpm. But I see you are commanding 700 rpm idle and it does about 500 ish.
If you look at your wideband it is showing 21-19 in alot of areas. Then when the injectors cut out is shows around 17-19 then it bangs back down to 13. The O2 readings, the injector duty cycle drops out when you shift. You may have some wires that are getting stretched, but its hard to say. They come back in after the shift, but it is DANGEROUSLY lean in too many areas man.
I am really surprised it has held up this long. You do not know if it is knocking because you have the PE knock retard set to zero.
Have you drilled a hole in the tb or made it larger?
The engine is prob close to being done, but honestly if you want to try and get it to run ok and drive better, then you would have to start over from scratch. You have not changed a whole lot, so that is good, but honestly getting the AFR to come in right is going to be hard to do safely on the street.
Your fuel trims look like crap. They max out immediately then come back in then back out. How does this thing run like that lol. Esp at such an rpm. But I see you are commanding 700 rpm idle and it does about 500 ish.
If you look at your wideband it is showing 21-19 in alot of areas. Then when the injectors cut out is shows around 17-19 then it bangs back down to 13. The O2 readings, the injector duty cycle drops out when you shift. You may have some wires that are getting stretched, but its hard to say. They come back in after the shift, but it is DANGEROUSLY lean in too many areas man.
I am really surprised it has held up this long. You do not know if it is knocking because you have the PE knock retard set to zero.
Have you drilled a hole in the tb or made it larger?
The engine is prob close to being done, but honestly if you want to try and get it to run ok and drive better, then you would have to start over from scratch. You have not changed a whole lot, so that is good, but honestly getting the AFR to come in right is going to be hard to do safely on the street.
12-13-2011, 12:46 AM
#10
TECH Fanatic
Thread Starter
I have a feeling you are shooting yourself in the foot right now with the extreme you are going to. Stop chasing your tail. Let do first things first and go from there.
Your fuel trims look like crap. They max out immediately then come back in then back out. How does this thing run like that lol. Esp at such an rpm. But I see you are commanding 700 rpm idle and it does about 500 ish.
If you look at your wideband it is showing 21-19 in alot of areas. Then when the injectors cut out is shows around 17-19 then it bangs back down to 13. The O2 readings, the injector duty cycle drops out when you shift. You may have some wires that are getting stretched, but its hard to say. They come back in after the shift, but it is DANGEROUSLY lean in too many areas man.
I am really surprised it has held up this long. You do not know if it is knocking because you have the PE knock retard set to zero.
Have you drilled a hole in the tb or made it larger?
The engine is prob close to being done, but honestly if you want to try and get it to run ok and drive better, then you would have to start over from scratch. You have not changed a whole lot, so that is good, but honestly getting the AFR to come in right is going to be hard to do safely on the street.
Your fuel trims look like crap. They max out immediately then come back in then back out. How does this thing run like that lol. Esp at such an rpm. But I see you are commanding 700 rpm idle and it does about 500 ish.
If you look at your wideband it is showing 21-19 in alot of areas. Then when the injectors cut out is shows around 17-19 then it bangs back down to 13. The O2 readings, the injector duty cycle drops out when you shift. You may have some wires that are getting stretched, but its hard to say. They come back in after the shift, but it is DANGEROUSLY lean in too many areas man.
I am really surprised it has held up this long. You do not know if it is knocking because you have the PE knock retard set to zero.
Have you drilled a hole in the tb or made it larger?
The engine is prob close to being done, but honestly if you want to try and get it to run ok and drive better, then you would have to start over from scratch. You have not changed a whole lot, so that is good, but honestly getting the AFR to come in right is going to be hard to do safely on the street.
Honestly the engine should be done considering the amount of runs i have on it, it was about time something happened lol.
The 21 afr you see is at the beginning of the run is when i am using the lingenfelter 2 step. As you can see when i drop the clutch it goes straight to 13:1 like its suppose to. I also have larger injectors if you have not noticed the 1% duty cycle lol. I originally thought it was the injectors causing this so i bought some and put them in there, its no worse or better with them in there now.
12-13-2011, 11:49 AM
#11
Did all of this happen before or after the 2 step install? How are you using the 2 step? Just for launch or for studder during shifts? If you follow the scan, it goes in and out during all the shifts. What gear do you pass the traps in? What RPM do you launch at?
Who turned the PE knock to zero?
If the car runs bad when normally driving, it will have a tendency to have an effect on WOT running as well. They will compliment each other even though they are not completely related. I know you may not care how your car drives, but it does lol.
Who turned the PE knock to zero?
If the car runs bad when normally driving, it will have a tendency to have an effect on WOT running as well. They will compliment each other even though they are not completely related. I know you may not care how your car drives, but it does lol.
Last edited by gectek; 12-13-2011 at 12:04 PM.
12-13-2011, 02:56 PM
#12
TECH Fanatic
Thread Starter
Did all of this happen before or after the 2 step install? How are you using the 2 step? Just for launch or for studder during shifts? If you follow the scan, it goes in and out during all the shifts. What gear do you pass the traps in? What RPM do you launch at?
Who turned the PE knock to zero?
If the car runs bad when normally driving, it will have a tendency to have an effect on WOT running as well. They will compliment each other even though they are not completely related. I know you may not care how your car drives, but it does lol.
Who turned the PE knock to zero?
If the car runs bad when normally driving, it will have a tendency to have an effect on WOT running as well. They will compliment each other even though they are not completely related. I know you may not care how your car drives, but it does lol.
I think i have it narrowed down to what it is, i had pulled the plug the other day and there was oil on it, compared it to the plug in the cylinder next to it and it looked fine. Gonna get the non fouler to see what it does, also gonna shut it off at the track while its messing up and see what the plug looks like. Gonna put a couple of clean plugs in it before the run for a good test.
