Fuel injector testing, continuous spray ok?
Thread Starter
|
4wd Low
Joined: Mar 2016
Posts: 11
Likes: 1
Fuel injector testing, continuous spray ok?
This question is about injector behavior on a 1995 Ranger 3.0 V6. Using a homemade push-button tester (like one of the many you might see on YouTube), the injectors would continuously spray for as long as I held the button (although I never held the button more than 3-4 seconds). However, a few months ago while working on my 03 F250 V10 gas burner, the injector would spray then stop even if I held the button a couple of seconds. Another spray required an additional push of the button.
Are the Ranger injectors bad or are is it that the technology is different between the 95 Ranger and the 03 F250?
Are the Ranger injectors bad or are is it that the technology is different between the 95 Ranger and the 03 F250?
FTE Legend
Joined: Jun 2006
Posts: 31,930
Likes: 1,499
From: Ottawa, Ontario
When you were testing the 03 injectors did you have them out of the motor in a test jig? That behaviour seems strange to me but maybe the newer injectors include some new current limiting circuitry. I know the old injectors don't have anything like that.. they will stay open until you disconnect power or it burns itself out so any test jig you use should have some kind of current limiting.. you should not just connect the injectors to a 12v battery for example.
Thread Starter
|
4wd Low
Joined: Mar 2016
Posts: 11
Likes: 1
Yes, the injectors were off the motor in both cases. The testing on my 03 F250 was a few months ago and testing on the 95 Ranger was last weekend. Comparing the injector behaviors between the two vehicles, I thought I had a bad injector on the Ranger when it stayed open when energized...but when all six of them did that, I figured it must be older technology. I think you've confirmed my suspicion by stating the older injectors would stay open until power was disconnected. Many thanks!
So, instead of buying a set of injectors, I bought a seal kit for each injector from NAPA. Echlin part number CRB 212085 for about $6 each and contains the pintle cap, washer(seal) and both O-rings.
One other concern with the injectors is that Autozone's online reference guide says resistance between the two terminals on the injectors should be in the 4-11 Ohm range. I consistently got 13.8 to 14.2 on each one. Being the original injectors with 140K miles, I'm led to believe one of two things: they're all wearing out at the same rate -OR- the 14 Ohm range is not really out of spec. Opinions on which?
So, instead of buying a set of injectors, I bought a seal kit for each injector from NAPA. Echlin part number CRB 212085 for about $6 each and contains the pintle cap, washer(seal) and both O-rings.
One other concern with the injectors is that Autozone's online reference guide says resistance between the two terminals on the injectors should be in the 4-11 Ohm range. I consistently got 13.8 to 14.2 on each one. Being the original injectors with 140K miles, I'm led to believe one of two things: they're all wearing out at the same rate -OR- the 14 Ohm range is not really out of spec. Opinions on which?
FTE Legend
Joined: Jun 2006
Posts: 31,930
Likes: 1,499
From: Ottawa, Ontario
Your ohm measurements are fine. An injector is just a precision solenoid which is just a coil of wire that when energized acts as a magnet and opens a valve allowing fuel to flow. The coil would only degrade if subjected to an over voltage or too much current but the injector drivers inside the PCM are designed to provide just enough power to make them work so they rarely fail electrically. A bad injector would measure at a lower resistance or as an open circuit.
Thread
Thread Starter
Forum
Replies
Last Post
IDI-Charlie
1999 - 2003 7.3L Power Stroke Diesel
23
Oct 28, 2020 08:14 AM
fordman1954
1987 - 1996 F150 & Larger F-Series Trucks
3
Apr 5, 2007 05:16 PM
