I have a 1992 C4 and want to replace my stock injectors with new stock size injectors. I saw FIC as a source on these forums but after looking at their site I see LS1 but NO LT1 listed. I believe I need 24 size. Does anyone know if these are available.. Car has sat for 5 years with same gas and will turn over but not fire.. I plan on changing gas, blowing out fuel lines and checking fuse and fuel pump . Right now Im assuming injectors and filter are junk possibly fuel pump too. Will start with new gas and work my way from there. Thanks TS

 

If you log onto their website then click on rebuilt injectors, then GM cars, you will see rebuilt Bosch injectors for 92 LT1 for $189 for the set. He really dials these in for the specific car. I purchased the same set for my 92 when I first purchased it and could not have asked for anything better in quality or customer service. They seemed to smooth out idle and it just seemed smoother. My 92 only had 17,000 miles on it when I bought it 5 years ago but I did not want to stay with the original injectors and was happy I didn’t.

 

I installed FIC's Rman Bosch injectors on my 96' LT4 that really didn't need injectors, but I figured WTF... they are 24 years old, so why not? I did the fuel pressure regulator, fuel filter and fuel pump as preventive maintenance as well... maybe overkill??
FIC' s injectors work great!! Car definately runs better!! Call them, they will give you expert advise, and get you up in running in no time.
BWT... Fuel pump is easy, not terribly expensive. If your car has been sitting, I would drain n flush or replace the fuel tank, replace the fuel pump, blow out the lines, new fuel filter and regulator, injectors from FIC.... You will be amazed at how good it will run!!

 

There is a place called South Bay Injectors located in NY near NYC. I have bought several sets of Fuel Injectors from them. I had been doing business with them before I hear of FIC. I would not venture to say one is better than the other but it is another option. The more options there are the better it is for the consumer!

I had a set of their injectors in my C4 and have never had any complaints.

Refreshing the entire fuel system like BigBill did will clearly make your Corvette Happier and run better. Fuel Pressure is so important to the C4's.

Don't forget that the Oxygen Sensor is only designed for 24 months or 50 k miles on the pre-1996 Corvettes using OBD1. A lot of folks leave the part until it starts to cause problems. This one little inexpensive part can improve your economy and Performance all at one time.

 

I'm gonna go ahead and call a little BS on this one. At a bare minimum, the O2 sensors on the 94-95 Corvette are exactly the same as the one for the '96. This makes sense since the 94-95 Corvettes had three O2 sensors, one of which was after the catalytic converter and was tied into prototype OBD2 code in the PCM. You can access this code via a GM scan tool or PC software even though it's not available on the dash and won't talk to an OBD2 reader. As I don't have experience with the 92-93 or even older I can't speak for those, but at least the 94+ use the same part (for the same reason).

Absolutely do check your O2 sensor operation and replace as necessary, because they're a critical part of your vehicle's operation.

 

I have a 96 LT4 and I sent my old injectors to FIC for rebuild. They had sat for 11 years. He called and said they were no bueno and locked up. He sold me a set of Bosch rated for my car. Then he took a little time cut the small groove around the top so I could run he standard injector clips that hold them to the rail., normally a double o-ring will suffice. It wasn't cheap but my car runs good. Quick response and starts almost instantly even after sitting for a week or more sometimes. It's nice when you get a product that works. Through my extensive rebuild I have paid top dollar for a lot of stuff that was pure crap. Brake parts for one are a total disaster for the C4 community. This guy sold me what he said he would sell me and it works.

 

Thanks for the compliment! I just wanted to make note, that 1996 LT4's have four 02 sensors, one in front and one in back of each catalytic converter . I just purchased 4 new AC Delco 02's and will be putting them in shortly. Some might argue that this is vain replacement- I say no, that at almost 25 years old, they are suspect at best.
I try to stay OEM for parts, but many parts have been discontinued... so aftermarket is the only way. Unfortunately, that means made in China 90% of the time.
I HATE putting Chinese parts on my Vette!!

 

Yep! In '96 they went to full OBD2, which required them to use four sensors instead of just 2 (the 94-95 could've had just two and would've been fine, but they were doing testing to prepare for the '96 transition and so added the third). The two in front of the catalytic converter are the important ones; they tell the PCM how to adjust fueling when the car is cruising along at operating temp. The rear two are far less important, and generally only need to be replaced if they're throwing a code or you've melted a catalytic converter doing something silly. The latter two only measure the efficiency of the catalytic converters to make sure they're still operating within spec and aren't actually used to adjust fueling.

Best of luck, super jealous of your LT4!

 

The life span of the Oxygen sensors was determined by someone at GM Not me. All OBD1 cars are supposed to replace their Oxygen sensors at 24 months or 50 k miles. OBD2 cars double those numbers to 48 months or 100k miles. Today with the 2020 Cars they don't have a recommended replacement time anymore.

On a vehicle with OBD1 the oxygen sensor did not trigger any CEL in my Car when the O2 finally died, it just went into "Limp mode". I ended up making to a parking lot where it had to be towed as it was UN-drive-able on the roads around here.

Are the Oxygen sensors you are using the "Heated" type? Those should last longer than the UN-heated units. I am using Heated Oxygen sensor on my C3 and they are great as the engine gets to "Closed Loop" operation very quickly

When the O2 does finally start to fail, the mixture will get richer as a default and this can cause other problems down the line like plugged expensive catalytic converters. Older Oxygen sensors will also sometimes start to "cool off" at long stops and put the Engine back into "Open Loop" until the exhaust heats it up again and it switches back to "Closed Loop".

When replacing the O2's on a car with both "Upstream" and "Downstream" Oxygen sensors they recommend that you always replace both the Upstream and Downstream as a pair.

There have been people who report having used the same O2's for 15 to 20 years and "claim" they still work "perfectly". I have my doubts but this is what they claim. I know for a fact that the signal gets narrower as the units age. What I mean is that instead of sending the ECM a .1 to .9 Vdc signal the signal will become (for example) .3-.7 and this will still let the ECM work but nowhere as well as a fresh unit. The other thing the O2's do is they start lagging in the delivery of the signal and this makes problems as the ECM needs constant updates to keep the Fuel mixture correct. When the signal start to lag the ECM is left hanging and might make an incorrect air-fuel calculation do to old data.

Being as inexpensive as the Non-heated Oxygen sensors are I still suggest we keep up with GM's recommendations. Our engine will be more economical and potentially make more power with fresh oxygen sensors.

I try not to use anything Chinese on any of my cars. I have been so turned off by the high failure rate of anything made by them. I even avoid those cheap tools they are dumping on us.

Best Regards,
Chris

 

That's fine. But again, the exact same part is used on the 94-95 as on the 96. Precisely the same. Zero difference in the part number, placement, or operation. So if the recommendation is 48 months or 100k miles for '96, then '94'-'95 can get away with the same. If the recommendation for '95 is 24 months or 50k miles, then the '96 would be the same. One of these premises is incorrect. As I don't have long-term test data to prove which of your premises is incorrect, I will just say that datalogging software for the 94-96 exists, and if someone had both and was willing to datalog the car for that long, it could be put to bed. Me personally, I'll just continue to check the data and replace as necessary according to said data rather than worry about which of those recommendations is the correct one.

What was year was your C4? Again, I can state with certainty that this would not happen on a 94-95, so I'm curious which C4 you had that exhibited this strange behavior.

All 1994-1996 Corvettes used heated O2 sensors. I don't have an earlier car (and thus don't have an earlier service manual) to confirm their type, but if the photo of the Bosch OE product on Rockauto is correct, then the '93 and earlier use unheated O2 sensors. Perhaps that's where the confusion earlier came from? Perhaps instead of "OBD1" and "OBD2" you actually meant "Unheated" and "Heated?"

It may be recommended, but if you understand how the system works, you can get by with just replacing the front two. The rear two are only important in the sense that if they send a 'fail' signal to the PCM, you won't pass a smog test.