: 1995 Concours, Fuel injector size?



ED's85GT
01-24-05, 09:18 PM
I have searched.
I'd like to know what the OEM rating is for the injectors.
(I have a brand new set of Bosh 19LBH/hr sitting around
and i was thinking......)

Thanks.

Ed

mcowden
01-25-05, 12:37 PM
I wouldn't do that if I was you... Bbob will spank you for that. And I'll just repeat what I've been told many times, ignored, and lived to pay for it: "If it ain't broke, don't fix it." Were the Bosch injectors tested with the Northstar engines? I'll give you three guesses...

ED's85GT
01-25-05, 08:25 PM
I also drive a 1985 FieroGT with a 1991 Deville 4.9 and 4T60E,
this 4.9 (82,369 miles) ran good when i put it in.
I installed a set of Bosh 19Lb/h injectors (even though
the original Caddy injectors were good, had a few with high ohms
and a couple with low ohms, but all within specs)
and the difference was very, very noticeable, that 4.9
runs very well now.

I have another set of Bosh 19LB/H injectors (brand new)
I have very little to loose by trying if this Bosh set is the
correct size.

Ed

mcowden
01-25-05, 11:30 PM
Why would new off-brand injectors make any difference if the old ones were in spec? If the Bosch injectors allow more or less fuel per given pulse width, why does that make anything better? An injector is a pretty simple device. It's just a solenoid valve. It opens and closes for specific periods of time based on signals from the computer. So, if the tables in the PCM can compensate for differences in flow rates from the different injectors, that just puts you back at the original ratio, correct? Where's the advantage here? I'm not trying to prove you wrong, I just don't understand why it would help anything if the original injectors were fine.

:hmm:

eldorado1
01-26-05, 03:08 PM
I just don't understand why it would help anything if the original injectors were fine.


It's not just a valve, it's a valve and a nozzle. If that nozzle gets crudded up, you'll be spraying streams instead of mist. 60k is more than enough to crap out an injector. I tested my 66k injectors, and 4 of the 8 were leaking... more than leaking, more like stuck partly open, and spraying streams.

As far as what a northstar injector size is, I am almost positive it is 19#/hr. Well... <ahem> either that or 20 or 21lb........ I forget. I know it's smaller than the stock 4.6 mustang's 23#....

ED's85GT
01-26-05, 10:23 PM
Why would new off-brand injectors make any difference if the old ones were in spec? If the Bosch injectors allow more or less fuel per given pulse width, why does that make anything better? An injector is a pretty simple device. It's just a solenoid valve. It opens and closes for specific periods of time based on signals from the computer. So, if the tables in the PCM can compensate for differences in flow rates from the different injectors, that just puts you back at the original ratio, correct? Where's the advantage here? I'm not trying to prove you wrong, I just don't understand why it would help anything if the original injectors were fine.

:hmm:

The Bosh injectors atomize(sp?)the fuel better and have a better
pattern for more efficient combustion. More efficient combustion=
more power and better MPG, which is exactly what I experienced
with my 4.9 powered Fiero.

Ed

mcowden
01-27-05, 02:43 PM
OK, if you say so, but I've never heard of a better spray pattern injector before. Seems to me that if the spray pattern is better, it's because it's new and not crudded up. If that's the case, cleaning should restore the original pattern. The nozzle is just a hole of a specific (tiny) size. There's nothing there to affect the shape of the spray or the quality of the atomization that I can think of. What causes it to have better atomization? Why wouldn't cleaning accomplish the same thing at a lower cost?

Again, I'm trying to learn here, not criticize. Help me understand.

94CaddyConcours
01-28-05, 07:01 PM
I have a 94 Concours, Yes i have a problem with the injector. Why= everytome i replace the fuse on the evenside of the engine of the fuel injector it always burn out. When i replace it it doesnt burn out ontil i shut it down and restart it.

32V_DOHC
01-28-05, 10:48 PM
Injector rating is 23.5 lb/hr according to Ghosst. as far as changing them you might pull them and check the tips for deposits. The factory injectors are fairly deposit resistant. The bosch pintle type injectors are not. I would also be highly suspect of claims that the Bosch injectors are better in terms of atomization. They came first and the ball type and disk type injectors were designed later to improve spray pattern and reduce clogging. I would want to see hard data.

94 sounds like you have a short or a shorted injector or a bad injector driver. One possiblity for the blown fuse is the high duty cycle for startup. IOW the injectors are opened longer to provide start fueling which would draw more amps. I would disconnect the 2 connectors over the trans where the wiring goes into the intake. There will be a 8 wire connector this is the injector return. There will also be a 6 wire connector. The wires in cavities c and d provide injector power. Test resistance between c (6 wire) and b(2), d(3), f(5), and h(8) and between d (6 wire) and a(1), c(7), e(4), and g(6). The resistance should be 12-16 ohms. If any dont meet the spec remove that injector and test it. Replace if shorted. Repair wiring as necessary.

HTH

John

eldorado1
05-26-05, 11:00 PM
So are we fairly certain it's 23.5lb/hr? I want an educated guess to my injector sizes when I go for boost.....

eldorado1
06-01-05, 03:01 PM
hmmmmmm? :confused: