1dirtyZ

iTrader: (1)

i just switched from high impedance 75 lb injectors to 160 lbs/hr low impedance bosch units. i also got the AEM conveter box as well as the racetronix plug and play harness for the ls1.

well i hooked everything up and tried to start the car , but no luck, i went over everything and it seemed fine. the injectors were not firing at all, so just to make sure, i plugged the stock harness to the injectors and the car fired right up ( i shut it down after a couple of seconds to prevent any damage to the pcm)

here's a list of what i tried to get this thing to work:
- i swapped boxes and harness from another car that was running and nothing changed ( this ruled out the harness or box being bad),
- i also tried hookling the box to a seperate battery (+ and -) but no luck either.
- went as far as using another pcm from a car with the same combo, but no luck.

any idea what it can be , it seems i'm not getting any signal from the box to the injectors , what could be causing this? do i need to change anything in my tune to make the box work ( i did scale the injectors to the right size)?? or am i missing some thing ?

i'm out of ideas now and need some insight , what do you guys think?

black98ws6ta

iTrader: (77)

I tried to do the same exact thing you are and the car acted the same. I believe we came to the conclusion that the injector pulsewidth needed to be so small that the stock computer would not fire it. I could start it up all day long by spraying alittle carb cleaner in the intake. It would run fine untill it was time to start-up again.

I know that a select few got this set-up to work, but at the time I did not have the brains or money to figure it out.

You should not have to do anything to the tune for the box to work.

sevanseriesta

iTrader: (34)

please update this when you find out the solution.. I am also getting ready to do this same install.

1dirtyZ

iTrader: (1)

black98ws6ta, which table excatly do i modify in hp tuners to get the cranking pulsewidths smaller?

ozws6

iTrader: (25)

When you started the car with the driver box unplugged with the 160s installed, what was your injector IFR set at in the tune?

1dirtyZ

iTrader: (1)

it was supposed to be 160 .
(thanks for the pm , will try that today)

1dirtyZ

iTrader: (1)

well no luck today . i'm out of ideas .

we tried everything, we grounded everything and also went as far as using different injectors.
and just to make sure , i took the onverter and harness off and put it on another car and it fired right up! so i'm sure the thing is working.

this only leaves me with one theory,,, that the signal from the stock pcm is weak and the converter can't read it . could this be true?

black98ws6ta

iTrader: (77)

You put the 160's and the box on another car and it worked?

417 Motorsports

iTrader: (2)

So you had the stock computer running the 160s with no driver box for a few seconds????

Im still curious to see if a set of 160s and just 2 resistor boxes (commonly found in import cars, ie. accords, preludes, dsms) would work... all they do is change the impedance of what the computer sees... why would this not work????

ozws6

iTrader: (25)

That might be the case. I would switch the ECMs out again and hook up the driver box and the 160s to test out your theory.

1dirtyZ

iTrader: (1)

i did hook up another pcm , and another converter box and another converter harness , and nothing.

i'm going to try another engine harness, maybe that is where the issue is somehow.

common sense rules out everything except where the impedance converter harness connects to the vehicle ( and that is only one positive wire and a ground), and i already tried different locations and even grounded the block to the chassis and to the extra batt. we also had a running car connected through jumper cables and still nothing. so that was the last thing i didn't check.

1dirtyZ

iTrader: (1)

i just got word that the car fired right up!!
the guys at the shop installed another engine harness and the thing just sprang to life

apparently i have an issue with my stock harness, so i told them to check it wire by wire and see where the issue lies.
cant wait to get back home and get to tuning this thing !

ozws6

iTrader: (25)

Glad you were able to find the issue. Those electrical gremlins can be a pain. Good luck with the tune!

sevanseriesta

iTrader: (34)

whew scared me.... I was worried that it was going to be something more serious

1dirtyZ

iTrader: (1)

man was i relived to hear that it is working now.
i turns out many moons ago i had two injector plugs have their wires cut right at the connector ( actually right in the rubber insulator), so i cut all the connectors and spliced in new ones. well back then i was told the polarity of the injector was not an issue, so i just hooked them up with the red wire on the new connector to the colored wires on the harness , thinking the other would just be a ground.

so with the harness plugged in it would work ( cause the injector didn't mind which wire came in where), but it turns out on the racetronix harness the signal wire i had was going no where !

well i'm just happy i'm over that bump,,, now its on to the next one

sevanseriesta

iTrader: (34)

glad that it is running...