im pulling my hair out trying to figure out what wrong with my tii....

i have made another thread about it going lean and what i have tested... so ill keep that out of this thread.

What i need to know is some info about injector spray patterns and the flow.. or lack of flow from them.



alright i pulled my secondary fue rail out some and zip tied the injectors into the rail, plugged the primairy clips into the secondarys. turned the key and checked for operation and spray pattern.

both injectors showed a cone shaped spray pattern and were really even.
these injectors are 1600s and have about 4k miles on them before i got them. i have put about 1000 trouble free miles on them and now im going lean in boost.


im running premix, and my fuel filter was 3 years old... now i have changed it and im wondering if the premix and clogged filter somehow has something to do with limiting the flow of the injectors? like they are clogged... but still spray a even panttern? is that possible?

 

How do you know the injectors are at fault? There are other causes of lean mixtures. Have you checked fuel pressure? Fuel pump voltage?

 

Agreed, something else is most likely the cause of running lean all of a sudden

(and i'm not just saying that cause i think those are my old injectors...)

I screwed up once and hooked the FPR up to the wrong vac nipple after having the UIM off.. one that didn't see boost, only vac, and damn near blew the car up.. thank god I had the wideband hooked up....

Makes me wonder about using a rising rate FPR when i have a programable ECU......

 

i have tested, checked, or changed everything else.

here is the thread i made a few days ago lising all that i have done.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/my-fuel-system-problems-part-2-a-474531/




im at my wits end. it goes lean as **** when the 1600s come on. the staging point is set for 3psi.



seeing as i have checked just about everything else.... i was wondering if injectors drop in flow without messing up the spray pattern? is that possible?

 

I would think that's pretty unlikely. The crud that can build up on injector pintles over time and restrict flow will also upset the flow pattern.

 

new pintle caps... low mile injectors.

i swapped them out for another pair today and it fixed the problem.

rare maybe... but happened to mine. im sending them off to get tested and cleaned asap.

 

Laugh if you want, but I gotta say this for all you tight wads out there.

I had 3 stock injectors that were gummed up so that they wouldn't spray at all. I took an 18" piece of tubing (3/16" I think), and clamped one end over the input end of an injector. I filled the tube with carburetor cleaner from a spray can, and forced the other end of the tube over the big end of a basketball inflation needle. Then I poked the needle into a basketball to get about 10 psi of pressure. Finally, I took turns letting it all soak, and applying 12 volts to the injector terminals until they dribbled (sorry). Then I kept on applying intermittent voltage until I got a nice spray pattern. I cleaned all 3 gummed injectors that way.

The amazing thing, is that when I eventually sent them to Cruizin Performance, Rich's before/after test report showed that my injectors were spraying very close to spec after being cleaned by my backyard method. So, it must have been effective.

Another thing. I added the basketball to my toolbox (it doesn't fit in very well) many years ago, when I realized that it was the perfect pressure source to test my stock wastegate actuator. Take the signal tube off the wastegate nipple, and put on your test tube. Poke the other end in your b-ball, and watch the actuator move.

If I find any other uses for the basketball, I think I'll seek a patent.

 

The basketball thing is the funniest/coolest thing I've ever heard of. I'm adding one to my toolbox tonight.

 

Awesome.



That is all.