I have an 01 lightning and my water temp gauge isn't working I changed the air charge temp sensor on the passengers side on top the intake manifold. I cannot find the water temp sensor is it behind the alternate or is there not one I tried researching it but could not find a good answer.

 

I even did the wire test on the air temp sensor on top of the manifold and when i turned the key the temp gauge went all the way to hot.

 

So it's not an engine swap, it's a factory lightning truck?

 

it is a swap. i just pulled the coolant temp sender from under the supercharger had to take the alternator and pulley bridge to get to it. Im will install temp sensor in a few and i will see if that was the problem. The temp gauge did work while i had the swapped motor in.

 

I replaced the sensor and the gauge does not work. I have a after market water reno gauge and the truck heats up to 180 that's it. Any ideas on making the factory gauge work I am worried that the ecm doesn't know when the engine is warm or not when I go to start it

 

You can integrate it inline with a coolant hose, -



There's also a couple other ways.

 

Ok but my problem is the temp does not show on my gauge cluster and I'm thinking the ecm does not know how warm the truck is. I replaced both air and water temp sensors. I even crossed the connectors and the temp gauge went all the way hot on the air temp and on the coolant temp gauge it moved Alittle past the cold went I crossed the connector. Could it be grounded out somewhere

 

I'm not sure I'm getting the whole story or understanding it. So what type of vehicle do you have the lightning engine in ? The 150's use a PCM btw. I don't really feel like playing 20 questions..

 

I have it in my 01 f150 that was a 4.2 L I have all the lightning parts such as pcm wireharness ect from an 01 Ford lightning. The temp gauge worked on the dash. A couple weeks ago the temp gauge stopped working on the gauge cluster. I bought an autometer temp gauge and installed it engine gets to 180 and that's it. So didn't think much of not having the temp gauge on the cluster not working. Now when I go to start the truck warm it doesn't start on the first try takes 2 or 3 tries when holding the petal to the floor. My truck is untuned at the moment. I replaced the coolant temp sensor under the supercharger. And replaced the air temp sensor on top of the manifold. Trucks temp gauge still doesn't work and won't start when hot right away. Also I am burning more fuel than normal. Any ideas I tried crossing the sensor plugs and the air temp sensor went all the way hot when I turned the key. The coolant temp sensor only went Alittle way past the c. Hope this clears everything up. The cluster is also a 4.2L with no tach

 

Replace your thermostat and check your fuel injectors for leakage.

 

Huh, iduno. Sounds like wiring IMO. Have you scanned it ? I'd scan it first with or without a CEL. Then run the wiring down, check the CHT harness. Yea, seems like you should be getting a CEL. It's also possible that you have two different problems going on. As said, the regulator can screw up a warm start, so can the MAF. Could also be the IAC. But, -I would want to know what's up with the cluster gauge as well. Not much help for yuh, but you have to start somewhere. Keep looking you'll find it.

 

Oh, keep in mind those wires like to break inside the insulation at times. So check power and/or continuity, specially at the CHT. One of mine broke inside the insulation there.

 

Also lol, User Fairlaner has a good write-up about adding an additional Temp gauge in the How To's on this site.

 

I check fuel Injectors not leaking I will have to check to see if I'm getting power first to the sensors. The termostat has to work because on my autometer gauge the temp goes up to 200 at first than goes to 180 and stays there. The maf and iac are brand new isn't the regulator one piece with the fuel rail? Like I said before I unplugged the coolant temp sensor and connected a wire to the sensor plug and crossed it the gauge on the cluster only moved alittle. Also sometimes the cluster gauge will move up Alittle than fall back down to cold while the trucks hot

 

Yea, it probably has to go thru the PCM, -then from the PCM to the cluster, - just guessing, I haven't those exact cluster wires down before. Have you looked at a diagram yet ? Also 180 isn't that far off (190 -200 being normal). That depends upon where your tapped.