65lb injectors wont idle.
 

I keep getting O2 sensors high voltage lights. I'm guessing these just can't be slowed down enough to idle properly? inj duty cycle is 1% constant.

Did you put 65s in just for the spray? Did you set your IFR? Is this an otherwise stock engine? Sorry if the questions sound stupid, just trying to get an idea of what you're trying to accomplish. 65s are pretty damn big, not to be running a big NA motor or a FI motor.

Look at the minimum injector pulse width limit and see if
that just happens to be the delivered Inj PW value in the
logs. If so that's probably what has you bound up. Now
to get the same as stock fuel shot you'd have to cut the
value by about half, and that may be below the actual,
minimum pulse width to which the injector can respond...
you might have to idle higher and skinny up the minimum
pulse width both.

How can I find out the min pulsewidth? The first thing I tried was rasing the idle to 1050. No luck. It must be the pulsewidth, no matter how large I scale the injector table I can't get leaner than 920 on the o2s at idle.

It runs great at part throttle.

I installed an ls6intke, and ported tb, with the injectors but otherwise the engine is stock.

I noticed there is no vacume line to the FPR? Is there a way to lower fuel pressure?

My last thought is to severely retard the timing at idle, so it has to suck more air. A trick I used to make my 3.8 idle with an overported TB. If it comes to that I'll probably just go back to stock injectors.

HPtuners is saying the min pulsewidth is 1.22, but I can't get it to go below 1.7? WTF?

What values did you use in the IFR table? 65# injectors at
a 3-bar or 4-bar rating? If it's not sitting on the min pulse limit
then you're probably fueling based on airflow and maybe have
more fuel shot than modeled?

I don't know about '98 fuel regulation what with the different
steel tank and all. But it might be a good candidate for a
manifold-referenced regulator, take out some pressure at
higher vacuum levels (like idle / cruise).

Not telling you how to build your car, but it sounds like some 42s would do, even with a fair dry shot. No?

https://ls1tech.com/forums/showthrea...tor+pulsewidth

Saved by the search function. Thanks for the help.

It idles now, but the fuel trims are all over the place large negative and positive.

Yeah I did that on the 3.8 and ended up running out of fuel. I figure this way when I get a built motor and a shot, I'll be set.

i'm going to say it and i'm probably going to get told again. but an injector can only run at such a low pulse width. and if you aren't getting the idle airflow/airflow period that they need to run properly (Above a 1ms pulse width) then you ain't gettin no further with them. switch them out and go with smaller injectors. you will be fine even spraying with 42#ers.

42#ers seem to be the cream of the crop here...as LOTS of people have them, since they will support a good bit of power too. I'm running them and have no problems at idle. only changed my min and default puls width tables by 10% (negative) and my offset vs. volts by 5%

car runs great ;)

but yeh, i think you have tooooo big of an injector.

Thos injectors are way to big for those mods, switch to some 42's, they will work just fine.

My vette runs 8.24/ 8ths, and it does it on 28lb injectors, max duty cycle of 90%, which is where manufacurers like keeping the duty cycles (80-90%). What were you thinking going with 65's on a basically stock engine?