91 Injectors replaced by GM with NOS in 2005

[BurnRubber]

I went ahead and replaced my injectors with the Accel 150821. I later found out the original multec injectors were replaced by GM in 2005. I ohmed all the multecs and they ran great. Is there any way to know if the Nos injectors GM installed were ever updated for ethanol or should I just leave the Accels in there?

[Paul Workman]

I went ahead and replaced my injectors with the Accel 150821. I later found out the original multec injectors were replaced by GM in 2005. I ohmed all the multecs and they ran great. Is there any way to know if the Nos injectors GM installed were ever updated for ethanol or should I just leave the Accels in there?

I'd highly recommend you leave the Accels in there!

My NOS injectors were installed (according to the Corvette dealer) by GM in 2007. They went bad very shortly there after - and MAY have been a contributing cause of a burned exhaust valve a couple years later!

Fact is, very often the issue with the alcohol damaged injector (windings) does not manifest itself until the injectors reach (nearly) operating temperature. So, if you were to measure the resistance when they were at room temp, finding them to read "normal" resistance e.g., 12 or 14 Ω is more common than not - i.e., giving a false "good" resistance value!

No reason to remove the Accels. They're functioning just fine in several ZR-1s; mine included - for well over 6+ years now w/ ZERO issues!

[secondchance]

Agree with Paul 100%. Contrary to the myth that only early ZR-1s had injectors that wasn't designed for ethanol blend, my 94 injectors were bad when I bought the car in 2000.
I strongly recommend staying with Accels.

[BurnRubber]

Well 6 years seems like a long enough test to confirm the Accels. My fuel trims are a little high at Idle and cruise but controlled at 138 as opposed to 128 for stochiometric. I guess I will keep the Accels in there.