Fluctuating Temp Gauge
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
ICVR: Motorcraft #GR-513: Suggested retail: $69.24
www.horizonpartsguy.com is selling it for $45.70
Other choices From other manufacturers...
ICVR: Borg Warner #R306: $49.99
ICVR: Napa Echlin #IR8: $63.99
www.horizonpartsguy.com is selling it for $45.70
Other choices From other manufacturers...
ICVR: Borg Warner #R306: $49.99
ICVR: Napa Echlin #IR8: $63.99
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Glad it is fixed. But, it doesn't take much oxidation to cause resistance, and with resistance you get an off-set voltage. IOW, the 5.5v the ICVR is supposed to create has the added voltage across the resistor so now all the gauges read higher. But, the off-set voltage changes with the current, and the current changes as the temp/fuel/oil pressure change. So, nothing is stable but everything reads higher.
Logistics Pro
Joined: Sep 2011
Posts: 4,491
Likes: 26
From: Algona,WA
I had an issue with a temperature sending unit that takes the coolant temp reading, I was driving along and all in the sudden the gauge goes way over to high, but my engine wasn't even fully warmed up yet. The part cost me $5. Good thing it wasn't overheating. I noticed with my truck the ambient air temp causes it to fluxuate a little bit. As long as it stays around the middle it should be OK. But I never totally trust those factory gauges...
New User
Joined: Dec 2016
Posts: 21
Likes: 0
ICVR = Constant Voltage Regulator
All of my gauge indications come and go as they please, all or nothing and all together. Yesterday off and on, today on ok. Is this a symptom of the ICVR rearing its ugly head? I have all gauges, not idiot lights.
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
ICVR is in no way a constant voltage regulator. Far, far from it. Read this on ICVR's: ICVR - ???Gary's Garagemahal. The links show the waveform the ICVR creates, which is ugly. And the page shows how to make one that works very well.
And, if your fuel gauge, oil pressure gauge, and water temp gauge are all dancing in unison then your ICVR is going bonkers.
And, if your fuel gauge, oil pressure gauge, and water temp gauge are all dancing in unison then your ICVR is going bonkers.
New User
Joined: Dec 2016
Posts: 21
Likes: 0
Guage problem
My problem was staring me in the face. Ignition switch is not spring back fully to run from start. It's not holding in the solenoid to engage the starter but not quite as far back as it should. Not getting power to gauges, wipers, heater fan. Just a "tic" of a turn ccw and everything comes to life as it should. Another item on my "to-do" list.
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FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Yes, that will do it. There's a lot of mechanism involved, including the tumbler, the rod, and the switch itself, and any of them can be the culprit. I recently had the steering wheel off, so dropped the column and pulled the switch and lubed it with a spray electrical cleaner/lube. And I lubed the tumbler and the rod. Then I put the switch back and aligned it as shown here: Ignition Switch - ???Gary's Garagemahal.
New User
Joined: Dec 2016
Posts: 21
Likes: 0
Switch
Replaced the tumbler back in the winter. The starter was trying to stay engages, so it had to be turned back by hand. Lubed the rod and thought I had it, but looks like I need to dig further as you suggested. The tumbler wasn't a bad investment as the old keys were worn badly.
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