I recently got a set of 450cc DSM injectors for my 91 tegra LS. At the tip of the injector one of the caps broke off on the end where it sprays. I wasnt sure how big of a deal it was, and my brother was helping me install them and said i should just go ahead and start it and see how it sounded. Well i started it, it ran fine. I took it for a test drive really slowly. It was sputtering some so i shut it off right away. My question is, is the reason its sputtering some because that cap broke off? OR Is it because i need to increase the fuel flow through them? Im about to put my turbo set up on my car. And i have a fuel pump im yet to install. I also have a Apexi AFC-II installed. So any help on that would be great. Thanks alot.

 

The pintile cap is in place basically to protect the pintile. As long as the pintile itself isnt damaged, you should be fine.

I personally would send them to cruzin performance and get them cleaned and have the pintile caps replaced if I knew one was broken off, to be on the safe side. An injector is NOT something that you want to fail, obviously, especially under boost.

 

do you think the reason it is sputtering some is because there is not enough fuel?

 

Unless the pintile is damaged, no.

Did you set the AFC to control the larger injectors, and did you install a resistor box or inline resistors?

 

didnt install a resistor box... and hadnt changed the AFC yet. Do i have to put a resistor box in ?

 

Actually you are a 91...which I believe has a resistor box stock.

I believe you have to play with the AFC a bit to get the injectors to drive properly. Try -35-40 across the table, see what happens.

 

alright thanks man ill tell ya if it works

 

Ok well i changed everything across the board to - 40 and it doesnt sputter anymore. But now it almost seems to hesitate a little when i shift. seems like its not got as much throttle response. Could that be because im running too rich since the turbo isnt on yet to use the extra fuel?

 

Another thing... my check engine light came on when i was just driving it. I dunno if thats a big deal or not.