Fuel Injectors

[ffvetteman]

Well now that its starting to get warm, its time to start working on the Z again. I am going to do some tests, but I believe that my injectors are bad. I am going to get the Accel if I do in fact need new ones, but not sure which ones to get.

What is the stock flow rate? My 92 is all stock short of a Samco air duct, so I wanted the stock injectors.

I cant seem to find what they should be.

Thanks

BTW for the guys who have used the Accel Injectors, how are they working?

[tccrab]

Originally Posted by ffvetteman

Well now that its starting to get warm, its time to start working on the Z again. I am going to do some tests, but I believe that my injectors are bad. I am going to get the Accel if I do in fact need new ones, but not sure which ones to get.

What is the stock flow rate? My 92 is all stock short of a Samco air duct, so I wanted the stock injectors.

I cant seem to find what they should be.

Thanks

BTW for the guys who have used the Accel Injectors, how are they working?

Mine are working just fine!

Accel 150121 if bought individually, Accel 150821 if bought in packs of 8.
The best deal is from Atlantic Speed Performance Parts, $249.88 for pack of 8. Plus they send a nifty "Tee" shirt with your order. There might still be a discount if you mention the ZR1 Net Registry.
http://www.atlanticspeed.com/
You'll need Marc Haibec's special "O" rings if your Z is a 90-93 for the primary injectors.
http://www.zr1specialist.com

What makes you think that your injectors have gone bad? Have you measured the resistance of the injector coils?
No sense climbing under the plenum if you don't absolutely have to...

TomC
'90ZR1 #792
Honorary Pirate

[c4koh]

I just tested my injector resistance tonight - all seem OK. They were cold though, but all between 12.1 and 12.4 ohms. I'll re-test when hot.

(I'm having some loss of power on 2ndaries..).

If it's any help, I created myself this diagram to speed up figuring the stuff out from the factory service manual:



... it's not as complicated as it looks ... The first relay is easy to get to, the second may need small hands with the battery in place. The ECM of course easy to get to, and the Ignition Diagnosic Connector - as the manual says - is sort of lying on top of the big cable-bunch just by the wiper motor...

[tccrab]

Very cool diagram!
I will be keeping a copy of it for future reference.

TomC
'90ZR1 #792

[ffvetteman]

I am not sure that they are bad at this point but it is a guess.

After I replaced the ECM, it was running fine for a bit, but then I could feel a pretty major loss of power under load. When I got toward the top of the RPM range, it would throw a check engine light. I ran that code and it said "lean fuel" (I forgot which code it was).

I was going to be checking the resistance next on the injectors, just have not got around to it. I just wanted the part #'s in case they are bad, I can order then right away.

What is the flow on them, 24# primary and 19# secondary?

[WB9MCW]

Originally Posted by tccrab

Very cool diagram!
I will be keeping a copy of it for future reference.

TomC
'90ZR1 #792

me too---nice of you to post it here c4koh


links for you to check out ff

injector tech page>>> http://www.rceng.com/technical.htm

http://listserv.corvettemuseum.com/c...zr1net&P=37183

http://www.flatlanderracing.com/accelfuelinj-gm.html

[c4koh]

I hope that the reference diagram is useful! I've had so much help here (and on the previous listserv) over the years - by people who know so much more than me - that I'm glad to offer whatever I can!!

I remembered I checked out my injectors about 3 years ago, and checked them yesterday - and was just puzzled for about 1/2 an hour trying to figure out exactly what the service manual, the listserv posts etc. were trying to say...

Anyway, I decided to write it down - it will surely speed up the process for future...

[1990 quasar blue]

http://www.autoshopracingengines.com/

432.00 for all 16.

[Ccmano]

Originally Posted by ffvetteman

I am not sure that they are bad at this point but it is a guess.

After I replaced the ECM, it was running fine for a bit, but then I could feel a pretty major loss of power under load. When I got toward the top of the RPM range, it would throw a check engine light. I ran that code and it said "lean fuel" (I forgot which code it was).

I had the same issue on my 90', turned out to be a bad fuel pump. Replaced both of them, problem solved. By all means check your injectors too, but I think you'll find the fuel pump is the issue. If you haven't already done it, replace the fuel filter before you do the fuel pump test. A clogged filter can cause the same problem.

Hans

[Aurora40]

Originally Posted by ffvetteman

What is the flow on them, 24# primary and 19# secondary?

I don't know the exact number, but the primary and secondary have the same flow rating. So it won't be something like 24 and 19.

FWIW, my injectors read fine too between 12-13 ohms hot or cold (read higher when hot). But they leaked. When I pulled the plenum I could see drops form on some of the injectors as they sat. Also before that I could let the car sit and sit and sit, and then crack the throttle blades open. You could really smell the gas vapors coming out.

I imagine the car made full power, though, the injectors weren't too bad. But idle, low rpm, and part-throttle driving was much smoother after replacing them. I went with Delphi '93-95 replacements on my '90. They were slightly less than RC's (and were available immediately).