How to Check a Fuel Injector's Resistance

Checking the resistance on a fuel injector needs to be accomplished in a very specific way. Check a fuel injector's resistance with help from an expert in the automotive industry in this free video clip.

Part of the Video Series: Maintaining a Car's Electrical System

Video Transcript

Hi, I'm Bob Holcomb from Apex Automotive in Great Barrington, Massachusetts. Today we're going to check the resistance on this 1996 Volvo fuel injector. All fuel injectors have a specific resistance that you can measure. I've looked this one up in the manual, and it tells me I need to be between 15.55 and 16.35 ohms of resistance. The first thing I'm going to do is remove the connector from the fuel injector. I'm going to be careful as this is a 1996 car, and these wires and this harness have been in a hostile environment its whole life and could be brittle. So, use caution when you remove the injector plug. I can see two electrical connections and these are the injector connections. I'm going to take my probes. Going to probe one side to the other and look for resistance. My meter tells me that I have 16.3 ohms of resistance. That's within specifications on the higher end of the scale. The reason that this injector is on the higher end of the scale right now is, we just had this engine running and it's warm. When the engine is cold, you can expect the resistance to be lower. If the resistance is out of specification, it doesn't necessarily mean that the injector's not functioning. It does mean that it could be showing it's age or getting ready to fail. After we've done our own test, we record each sensor and then see if they're all the same ohms. If one of them is far out of the scale, we know that that injector is probably failing or has failed. You'll plug your injector back in, being careful not to break the wire. And that's how to ohm a fuel injector. I'm Bob Holcomb from Apex Automotive in Great Barrington, Massachusetts.

Featured

Related Ads