UVCH Ohm test question

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Jun 28, 2014 | 11:43 PM

cutlass

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UVCH Ohm test question

I have a question for those who have ohm tested their UVCH at the valve cover gasket by unplugging the engine wiring harness at the valve cover gasket and taking readings from there through the injector solenoid.

What should the the ohm readings be from this point?

I'm seeing 4.0 to 4.1 on my passenger side. I haven't done the driver's side yet, but I just wanted to see if my numbers are in line so far.

Thanks,
Drake

Jun 29, 2014 | 12:13 AM

Firefighter 1406

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From: Northern Indiana

I thought it was anything over 2 ohms they needed to be replaced. I ohmed mine today and they were all 0.5-0.6 except one that was 1.1. I am pretty sure the lower the resistance the better. Are you having cold start issues?

Jun 29, 2014 | 12:31 AM

cutlass

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No start problems. The problem is a significant engine miss and a p0281 code. The PERDELS for cylinder 7 are between 0.0 and 5.0, bouncing around with no predictability.

Jun 29, 2014 | 07:19 AM

Tugly

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From: Puget Sound

You really want to test it from the 42-pin connector... this checks the wiring and the connections all the way to the injector coils and back. There is a UVCH link in my signature that gives a lot of detail.

The dreaded #7 - I hate that cylinder. My situation may be unique, but I should share what I have learned on Stinky: Any time my engine needs some form of attention, #7 is the "rattle tale". If my oil needs to be changed and it starts to bubble - 7 gets the air and starts knocking, plus I get an intermittent miss at idle. This is counter-intuitive because 7 is lower than 1 on the gravity scale, but there it is. If I get air in fuel, #2 and #7 get first crack at sucking it in... and they both "take one for the team". If I see a slight intermittent rise in PERDELs (about 2) on #2 and #7, that's usually air in fuel.

I hope this is of use.

Jun 29, 2014 | 01:43 PM

cutlass

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I'm actually trying to isolate the UVCH from the rest of the engine wiring harness as a possible issue. I'm just wanting to know what the OHM's should read at the valve cover gasket connection atop the engine towards the injectors. Mine are between 4.0 and 4.1. Is that what I should see there?

Thanks,
Drake

Jun 29, 2014 | 01:51 PM

Firefighter 1406

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From: Northern Indiana

Check out this post. #2 especially

https://www.ford-trucks.com/forums/1...g-testing.html

Hope it helps a little.

Jun 29, 2014 | 03:51 PM

Tugly

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From: Puget Sound

I recall a little over 3 ohms, but the important thing is that they are all the same and close to that 3-ohm mark. Your readings look good... what's next?