UVC Harness testing
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From: Gifford, IL
UVC Harness testing
I tested the glow plugs and injectors on my uvc harness and got normal readings on the glow plugs except one was at 92 ohms. I've also read that you dont want over three ohms at your injectors when testing the resistance from the high bank to low bank. Almost all of my injectors were slightly above three ohms, and some got up to 5.6 ohms. I was looking for a short in my harness, but thats what i found. Is that an acceptable level of resistance for injectors or could that cause a no start condition?
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From: THUNDER BAY
I think 3 or 4 ohms is normal for injector wiring last time I tested mine they were 3.5 ohms usually you can tell if you have a bad harness just by unplugging the connector you can smell burning.
on the harness with the 92 ohm reading was that where the injectors ohmed out at 5.6 ohms?
on the harness with the 92 ohm reading was that where the injectors ohmed out at 5.6 ohms?
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From: THUNDER BAY
I think 3 or 4 ohms is normal for injector wiring last time I tested mine they were 3.5 ohms usually you can tell if you have a bad harness just by unplugging the connector you can smell burning.
on the harness with the 92 ohm reading was that where the injectors ohmed out at 5.6 ohms?
on the harness with the 92 ohm reading was that where the injectors ohmed out at 5.6 ohms?
my apologies
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From: Gifford, IL
Well my sniffer aint the greatest so it looks like im just going to take the covers off and inspect the gaskets. Did i check the gasket correctly? Test the resistance of the glow plugs (outside two pins) and the ground, and the injectors by checking resistance from middle pin to the two pins on each side? Is there any other way i need to check the pins to look for a short?
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From: Silver Lake Dunes, MI
around 3.5 ohms is perfect. Above 4 is suspect. You need to work you way toward the injector solenoid with testing. Unplug the inside of the UVC and test there. If your resistance dropped then your looking at VC gaskets more than likely. Also test the soleniod right at its pins.
Do you have a no start condition right now?
Do you have a no start condition right now?
Post Fiend
Joined: Apr 2004
Posts: 12,835
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From: Silver Lake Dunes, MI
Well my sniffer aint the greatest so it looks like im just going to take the covers off and inspect the gaskets. Did i check the gasket correctly? Test the resistance of the glow plugs (outside two pins) and the ground, and the injectors by checking resistance from middle pin to the two pins on each side? Is there any other way i need to check the pins to look for a short?
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From: Gifford, IL
Right now it will start occasionally, but only runs for roughly 1.5 seconds. It can stay running sometimes at 600 rpm with the pedal on the floor. Unfortunately i didnt see any melted connectors. Do you mean take off the covers and check resistance at the connections there?
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Post Fiend
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From: Silver Lake Dunes, MI
Right now it will start occasionally, but only runs for roughly 1.5 seconds. It can stay running sometimes at 600 rpm with the pedal on the floor. Unfortunately i didnt see any melted connectors. Do you mean take off the covers and check resistance at the connections there?
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From: Gifford, IL
Ok im stuck lol...is there somethin i need to remove to get the passenger side valve cover out? I've tried about everything i can think of and i cant manuever it out. Any tricks or tips?
Post Fiend
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From: Silver Lake Dunes, MI
Remove the silver insulation from the heater box and under there is a small box with a vacuum line going to it. The box is held my two screws. Remove those and the box and the VC will come out.
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From: Gifford, IL
OK i got it off. I pulled the connection at the front no problem. I tried to getting the back one off but broke the part that holds it together on top. I struggled to disconnect them only to realize the plastic had melted together, one spot on each side. I would guess that to be the problem, but from the outside of the harness i get the normal resistance readings. Should i disregard those normal readings and assume thats the problem?
Posting Guru
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From: Cato Arkansas
if if the valve cover wiring harness is burnt at the connectors you can replace it with this
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