93 LX 2.3L low coolant temperature

I have a 93 lx 2.3L. 43k miles. I have flused and back flushed system. Replaced water pump, thermostat, temp sensor, lower hose and radiator cap. Coolant temp will reach normal when sitting at idle. Soon as I start driving it. It drops down to 130. Seems to go into limp mode. Code I got off jumping the port was 21 (coolant temperature out of range). I can't figure this out. Can anyone help??
 
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When you replaced the thermostat, was it the correct one? These engines are notorious for running "cold" in the winter.

the theremostat housing itself is a common cause. Was that replaced? When you put the stat in, did you index the thermostat so that it locks tight against the housing? In other words, stuff it in, then spin it until it seals against the housing as best that it can. If it's got a bleed valve in the stat (some do some don't), make sure it's pointing up (12:00), and that's all you can do.

When installing the thermostat, the two little legs need to make contact with the block. This forces the stat into the housing to seal it off. If it's not sealing against the housing, it will leak past and never warm up. I have had to throw an o-ring in behind the stat gasket (between the housing and rubber stat gasket) as a spacer to seal it up.

You will get a code for ECT if the engine is not up to operating temp (160+).
 
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I took this from another site that I can't link to here...

Are we talking temp gauge or what turns the fans on? Yours is a 8 plug engine. If so the gauge sending unit is in block under intake. The one that turns the fan is in the upper intake between #2 and #3 injector. The is also the ECT sensor for the computer. The computer tells the IRCM on passenger fender when to pull relay in and out. Maurice
IRCM info.
JR's Place - Ford IRCM Schematic & Troubleshooting
92 Mustang wiring diagram. Second page is diagram for the IRCM connections.
http://www.rothfam.com/svo/reference/92-93Mustang.pdf

It sounds like you replaced the ECT sensor. I think junkyardwarrior is on the right track, though - faulty or improperly installed thermostat. The only thing I don't like is that if the thermostat is stuck open it should take a very long time to heat up at idle. If it is leaking past as he is describing, though, I imagine that it could heat up at idle because there is low pressure from the water pump to push a large volume of coolant past the thermostat - once you get rolling, the increased pressure forces enough past that the car cools down quickly.
 
I have some diagrams from another forum and I don't have a sensor between the injectors. And haven't seen one on the block. I just installed a Motorcraft thermostat. This makes 2nd one Ive put in with no change. I have an aftermarket temp gauge im going to install today so I can see what is going on. Once I know for sure whether I'm overheating or under heating I will report back
 
Well....interesting and ironic.

Mine is exhibiting same symptoms. Wont' really warm up. Runs about 140 all the time unless sitting still. Replaced thermostat, installed an o-ring between stat and housing, verified it's sealing against the housing because I can't blow through it. Motorcraft 192.

Found a BNIB robertshaw 192, ordered it and will try next week.
 
The dash gauge should be thought of as an indicator on these engines, not as a thermostat... Both of my 2.3's have always indicated cooler than what the actual engine temps were...

Get the data from the ECT sensor before concluding that your coolant temps are too low...
 
Robertshaw thermostat did in fact help mine. It now gains temp quickly.

But....

the gauge still shows "low" temp all the time. So out of curiousity, I pulled the kick panel and accessed the computer. Back probed the ECT pins and watched the ECT signal; it is in fact getting hot (190); however the gauge doesn't really read hot. Probably has something to do with where Ford placed the sensor, may have cool water there-OR might be a wiring issue, dunno. Aint had time to fiddle with it.
 
I have a 93 LX 4 cylinder and no matter how far I drive it the gauge on the dash only ever reads at the bottom or the first line above bottom i bought the car a month ago and was told they replaced the thermostat I believe and it has a brand new radiator too so is it just a weird thing these foxes do or do I need to replace the sensor and if so where is the sensor
 
I have a 93 LX 4 cylinder and no matter how far I drive it the gauge on the dash only ever reads at the bottom or the first line above bottom i bought the car a month ago and was told they replaced the thermostat I believe and it has a brand new radiator too so is it just a weird thing these foxes do or do I need to replace the sensor and if so where is the sensor
The first thing you need to do is get a mechanical (actual) reading of your coolant temp.

Who knows, your gauge might be accurate. :shrug:
 
I would use an in-line mechanical temp gauge or a hand-held infrared temp sensor if you have access to one.

Fully warm, you should be right around 180 degrees. If that's correct, then your issue is in either the sender or the gauge itself.

Testing the sender with multi-meter isn't too difficult. I'm sure there are boobtoob videos:


View: https://www.youtube.com/watch?v=bPAIFL8VH9w&ab_channel=CarsNToys

I bought this from autozone it clearly works because it does change temp but when I point it at the radiator or the hoses it's only says like 80 degrees but when I pointed it at the exhaust manifold it read 94 degrees it was like a 25 minute drive to get where I am was that not long enough for it to warm up
 

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I would use an in-line mechanical temp gauge or a hand-held infrared temp sensor if you have access to one.

Fully warm, you should be right around 180 degrees. If that's correct, then your issue is in either the sender or the gauge itself.

Testing the sender with multi-meter isn't too difficult. I'm sure there are boobtoob videos:


View: https://www.youtube.com/watch?v=bPAIFL8VH9w&ab_channel=CarsNToys

What sensor is responsible for reading my temperature gauge for the coolant is it the ECT or the ACT and where are they located