Fuel injector impedance question

Last year I had replaced my fuel injectors. I didn’t need to but I was replacing the seals and I didn’t know how old those injectors were.

One of the replacements went bad (open circuit) and so I was planning to use 3 new and 1 old. I just tested the impedance and the new ones are 16-17 and the older ones are 11-12. They are slightly different models (the old has ‘A’ on it and the new has ‘B’).

Is it a problem to use injectors with different impedance like that? I was considering using the old ones since they’re the same, but I wasn’t sure if that was necessary.

 

I ended up installing the older ones since there was impedance consistency. Not sure if there’s any value in that but I’ll keep 1 or 2 of the newer ones on hand in case an older fails.

 

I would have sent the old ones off for cleaning and kept using them. People generally don't have issues with the DI injectors going bad just getting fouled over many many miles.

 

Thanks Johnny. I had considered trying to find somewhere locally to clean the older ones but as it is I’m nearly a month behind and I just need to get it finished and in the car. Hopefully they’ll be ok.

 

In terms of impedance maybe there is different flow ratings. I know with GM DI injectors for LS engines we have low, normal, and high flow injectors. Sometimes when they go bad we have to pull the part number off the injector to order the correct ones or it cause cause rich/lean conditions.

The A and B designation may be for a difference in flow.

 

Thanks for the thought. I did run the newer injectors (B) for a few months last year and it seemed to run the same as the older (A). I didn’t do any monitoring of fuel conditions though. I just assumed it was a newer revision of the fuel injectors, kind of like how some Mazda parts end with a letter denoting a revision.

 

That may be the case as well. It may not hurt to contact Mazda to ask them about what it means so we all have a reference on this forum.