dear friends,

i need a serious help i will be appriciated to find someone helps me .

i have an h2 hummer and heres the specifications .

hummer h2 2004
sts remote mount turbo system with garret 67 at 5 psi
cam shaft with specifications of 220 , 560 , 115 lsa
msd ignition wires
airflow senser jet
42# dolphin injectors
walbro fuel pump in tank
stall converter 3200
wideband
and gauges
when we tune the car it runs good but after 10 min the car gets lean and we cant increase the fuel .

shall i upgrade to 60# injectors ?
or the problem with fuel pump
any suggestions will be appriciated .

greetings,
Fairline

 

pump and injectors should be good to about 600rwhp.....maybe tiny fuel wires getting hot and losing voltage...fuel trims off? is fuel pressure not falling?

 

So you are saying that you can tune it correctly and then something "changes" after a little while and it goes lean?

Do you have an exhaust leak somewhere upstream of the wideband?
Does your fuel pressure fall off drastically?

 

Ya what are your fuel trims doing? So it sounds like it is going lean once it warms up completely?

 

thanks guys for the update .


we replaced the dolphi 42 injectors with simens 60 injectors will start tuning tonight hope it fix the problem .

 

42lb injectors aren't good for much power on the H2 in my experience. A move to 60's is a good move.

You've still got another issue though with tuning. An error that pops up after 10 minutes isn't your injectors. The swap to 60's should be driven by a lean creep at higher rpm.

Are you saying that you are running a Jet (brandname) Mass Airflow Sensor? Why? The H2 has stock MAF tables different from any other truck. Big Tex and I went over that well over a year ago when comparing MAF numbers on my Radixed set up. I wonder if you don't have screwwy MAF readings based on the change.

Also, how have you been tuning? Did STS give you a base program or did you start the tuning at home from scratch. We'd need some real detail to actually help. What tuning program are you using?

If you have HP Tuners then send me a copy of your tuning file and a good log file showing the problem.

 

dear charris ,

Thanks for your update .

so u mean i should use the stock air flow senser and take that aftermarket one ?



and for tuning yes there is a tuner in kuwait here his name is jassim u might know him since he joins this forum i guess . he is tuning the car i believe from scratch i think i will take the car and start tuning it by using pre tune . i wish if u can help me in this as if u recommend for me a programer to buy and i can work it out with ur help i will be appriciated if u have the time .

 

Put the stock MAF back in and start from there. I had a granatelli MAF and it made my truck do some screwy things.

 

thanks guys it seems that might be the problem will return the stock one and will let you know what happens .

Thanks for the help guys.

 

guys we tested the hummer today and exchange the air flow sensor back to stock one dolphi . the car almost 70 percent tuned and fixed all the problems the car is amazing and thanks for your help ppl u made one guy smile

now i need a tuning help if possible .
i exchanged two things , i added 60lb injectors and stock dolphi air flow senser

what am facing is
car has high idle if we lower it it will shut off and i faced this problem after adding the stall converter 3200 .

other thing is , turbo is doing 4 psi , am using remote mout turbo charger with custom front intercooler , is the intercooler is the reason of missing 1 psi ?

also wideband is playing up and down its not stabilized in close numbers . also the car is getting bit lean at full boost just lil bit lean , injectors are doing maybe 50 percent duty and still bit lean , would it be the fuel pump problem ? iam using walbro 255 . the tuner guy told me it should be pump problem .

if i remove the protection material from the air filter in turbo the one that sts send it to protect the air filter would i gain some hp ?
any help will be appriciated .