Substitutable parts--or Right vs. Wrong?!

[Anon.II]

I need to get to the shop and do something re my lame '91 (auto/non-turbo) Legacy,

and would like to have some sense of the community re the issue of whether

subbing one quite visually different injector is viable vs. what I'm seeing as

the recommended part (from several OEMs), before I have to argue/plead my case

(about possibly redressing the installation of a wrong part), and maybe limp away to another

shop. (And I see that the December "R&R #1 injector" cost me $118; part, $170.)

 

NB: The distinction in appearance of the auto vs. man.(&turbo) '91 injectors is consistent

across various brands (SMP, Beck/Arnley, GB, Airtex).

(rockauto's pics are great to compare--see:

http://info.rockauto.com/SMP/SMPDetail3.html?FJ446.html

http://info.rockauto.com/SMP/SMPDetail3.html?FJ521.html

 

FJ446 is exactly like the Sub. dealer's part (heck, maybe SMP makes if for Sub).

Those for automatic non-turbo have that extended tip AND narrow side filter;

those for manual have a blunt, recessed tip, and wide fuel-filter side!?

FJ521 is said to be for '91 Turbo (as per RockAuto, SMP).

 

When #1 injector went bad end of '007, shop put in an SMP FJ521 (along with O2 & knock sensors).

Subsequently, I noticed a few instances of some engine tapping/knocking never

heard before (say, going TO, but then not returning from, an errand)!?

Now, w/#2 injector found bad, I've done a lot of Googling & e-mailing,

and see that there is that marked difference in appearance between ALL of what

RockAuto show for manual vs. automatic trans., and the 521 one, for Turbo,

matches man. in look. (And I have non-turbo automatic.)

IS THIS A SHOW-STOPPER, grounds for complaint/redress?!

 

--Anon.II

[Anon.II]

I need to get to the shop and do something re my lame '91 (auto/non-turbo) Legacy,

and would like to have some sense of the community re the issue of whether

subbing one quite visually different injector is viable vs. what I'm seeing as

the recommended part (from several OEMs), before I have to argue/plead my case

(about possibly redressing the installation of a wrong part), and maybe limp away to another

shop. (And I see that the December "R&R #1 injector" cost me $118; part, $170.)

 

:-\ :-\ :-\

 

Ack, has NObody any experience with fuel injectors to shed some light on my

dilemma?? I'm realllly strung out re this puzzle!

 

[Anon.II]

:-\ :-\ :-\

 

Ack, has NObody any experience with fuel injectors to shed some light on my dilemma??

I'm realllly strung out re this puzzle!

 

Well, something from elsewhere, touching one aspect of this (Turbo vs. non-turbo;

note though that it's manual trans. vs. automatic in the cited RockAuto list (and is also

confirmed by some of the parts makers, with Turbo injector being yet a 3rd distinct model, matching in

appearance the manual one)).

 

And this "something" response is:

Yes, the different part could be the casue of the noise.

The spray patterns and densities are very different for the two, the OEM one having been

designed for higher mechanical compression at lower RPMs without preignition,

whereas the [FJ521 turbo injector] replacement they used having been designed

for lower mechanical compression at low RPMs and to provide sufficient fuel properly dispersed

for higher "boosted" compression at high RPMs when the turbo kicks in.

 

In short, the injector designed for the turbocharged engine conditions could be causing preignition.

I suspect your non-turbocharged engine has higher compression until the turbo kicks in.

 

:cool:

[yohy]

If you check this site out:

http://www.subarupartsforyou.com/cp_partlistbymod.php?model=Legacy&subcat=Fuel+Injector&year=1991

they list three distinct SUBARU part numbers for the '91:

1)FUEL INJECTOR FOR 1990-1991 NON-TURBO LEGACY WITH AUTOMATIC TRANS

2)FUEL INJECTOR FOR 1990-1991 LEGACYS manual transmission ONLY

3)FUEL INJECTOR FOR 1991-1993 LEGACY TURBO

 

only issue is the site doesn't give you a clear picture of the actual part. SO, you might go back and clarify exactly which part was used.

 

Sorry about not giving you more specifics, but after 25 years of driving Subaru's, I have never had to mess with a fuel injector.