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So ever since the T5 swap, my idle has been crap. The engine wanted to stall or tried to at every stop light despite me swapping out IACs and resetting the idle speed to about 750 or so.
So I finally installed a junkyard set of these 19lb injectors with the four squirter holes. The resistance of each injector checked in at between 14.8 and 15.1 ohms so I know they were electrically good. I wiped them all clean with just a rag and made sure there was no debris blocking each of the four squirter holes, lubed their original o-rings with oil and stuck 'em in the fuel rail. I also installed new intake gaskets with the exception of the lower intake to head mating gasket. I was considering having the injectors professionally cleaned and rebuilt with new filters, pintle caps and o-rings but decided to keep my $90+ to myself lol......
The engine fired up first try and holy crap is it smooth. This thing idles as smoothly as my '96 Cobra 4-valve engine did when I first bought the car (used). Barely any relearn time for the computer to remap the short and long term fuel trims but I did have to adjust my shift points or else the car would bog just a bit at the acceleration of the next gear.
I'll report back later with any increases or decreases in fuel economy.
 

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Discussion Starter #3
I don't remember seeing where the vacuum modulator line from the automatic transmission went to when I disconnected it. My guess is that it went to the vacuum tree mounted on the firewall and I did put a nipple cover over that exposed connection on the tree which lowered my idle speed and made it more tolerable.
Which vacuum line were you referring to?
 

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Discussion Starter #6
update on this.
after I installed the 19lb injectors and rerouted a couple vacuum lines, the gas mileage overall dropped by 25%.
yesterday I grabbed some 17lb injectors (the more preferred size as an upgrade) from a GM 3.1L engine, '99 Lumina and installed those in my '93 LX. I also put the vacuum lines back the way they were before my gas mileage tanked. The idle isn't quite as smooth as with the 19lb injectors but I don't have the bogging off acceleration like with the 19s either. Acceleration in 5th gear is more responsive than it was with the 14lb injectors.
 

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I think the EEC is programmed to run pretty rich even with the OEM injectors. From what I've gathered so far, Lean and Mean seems to work better on these cars.

I played with 19's (bosch design III's from Crown Vic), 17's (bosch III's again from Focus), new OEM's, and the 144cc Densos I have now.

For power, the 17's seemed to work best for me, but fuel economy was still off. The densos are giving me a mpg improvement, and with a 3" intake tube, the power is quite nice too. But I have to say the car runs it best right after a reset of the EEC. I'm thinking of changing the 12V constant power lead on the harness over to a 12V switched just so it "relearns" every time I start the car.
 

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i curently have not done the injector swap and was thinking about doing the 17lb injectors. i have a 93 mustang with an auto trans. im thinking of just buying them new. i was just wondering what cars came with these injectors exactly, and what should i look for. the guys at the parts stores i have gone to have never heard of such a thing and are no help at all. thanks.
 

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17lb ones:
00-04 focus w/ 2.0 zetec, or 99-03 escort zx2.
the injectors are grey in color.

I have a used set for $50 if u like
 

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Discussion Starter #10
17lb ones:
00-04 focus w/ 2.0 zetec, or 99-03 escort zx2.
the injectors are grey in color.

I have a used set for $50 if u like
$50?.......I picked up a used set of 4 at my local junkyard for $20. The GM 3.1L engines are a whole lot more plentiful than the 00-04 Zetec 2.0L engines or the zx2 escorts and they also use the gray top 17lb injectors.
 

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$50?.......I picked up a used set of 4 at my local junkyard for $20. The GM 3.1L engines are a whole lot more plentiful than the 00-04 Zetec 2.0L engines or the zx2 escorts and they also use the gray top 17lb injectors.
are the injectors in the GM 3.1 Bosch III's?
those have better atomization properties.

and if u go to a pick a part, just pull the injectors and put them in your pocket as you leave.
then they are even cheaper than $20.00
 

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and if u go to a pick a part, just pull the injectors and put them in your pocket as you leave.
then they are even cheaper than $20.00
even though that may be true, i dont know that i would let that fly openly. haha
 

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Discussion Starter #13
even though that may be true, i dont know that i would let that fly openly. haha
especially when he offered you a set for $50 ;)
 

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Discussion Starter #14
are the injectors in the GM 3.1 Bosch III's?
those have better atomization properties.
No idea if they are Bosch III's. They came from a '99 Lumina 3.1L. That was the latest year of GM models that Eugene Blanchard listed on his website, CadVision or HotRodCa or whatever it goes by now for a name lol.......
You're right about the fuel efficiency being "off" with the 17lb injectors though; I went from 28-30mpg with the 14lb injectors all the way down to 20mpg with the 19lbs and then up to 21mpg with the 17s. And thats highway mpgs. I had some soot on the O2 sensor that easily wiped off (guessing that was from the 19s, never had any soot before) but other than that, I don't know what the hell is going on with my mpgs. I've only got one DTC, 0172 and I've had that monkey since I swapped over to the ranger header a few months back. Even with that code, I was still getting 28-30mpg. I'm about to switch back to the factory 14s.
 

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bosch III's have 4 fuel spray holes and are a plastic body, thats how you can tell.

so far i'm liking the 144cc injectors, and since they run a tad leaner, with a tps operated relay triggering resistors for the IAT and ECT, I can get them to run richer with more ignition advance at the same time (or so the theory goes, I haven't wired up the "black box" yet).
 

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Discussion Starter #16
bosch III's have 4 fuel spray holes and are a plastic body, thats how you can tell.

so far i'm liking the 144cc injectors, and since they run a tad leaner, with a tps operated relay triggering resistors for the IAT and ECT, I can get them to run richer with more ignition advance at the same time (or so the theory goes, I haven't wired up the "black box" yet).
These definitely are not Bosch IIIs then; mine have a 6-hole disk spray pattern. My factory ones were four holes.
Reading around, the GM injectoes were prone to leakage pretty commonly. I'm going to switch back today to the 14s and see if the injectors are the sole contributing factor to the crap gas mileage.
 
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