My truck coolant sensor is showing -40. I think i understand a sensor needs to be replaced. Where is it at?

 

 

Thanks for that. Now the guy who hooked up his computer said that there were two sensors. One for the guage and another for the computer and the one for the compurter was the one needing to be replaced. Any truth to that? Is that the ect? 2003 7.3

 

Depends.... where are you getting the bad reading from? A Gauge? Scanner/OBDII Port?

If it's a gauge, it should have a separate sensor, usually in the port on the side of the waterpump.

If it's a scanner or from the OBDII port.... it;s the OEM sensor.

 

Im not sure. I know he said it was reading -40 which was default for bad. I dont have a clue

 

it was on an obdII port scann.

 

What codes did he come up with when it was scanned?

 

He didnt say. Just that the fuel pressure would drop below 400 and it ran like poop then climb over 500 and smoth out. To get fuel pressure regulator and. The temp sensor was reading - 40 causing hard start and white smoke.

 

I would look for someone else to help diagnose my truck in the future, because it sounds to me like this guy isn't necessarily up-to-snuff on our engines and is leading you down the wrong road.

White smoke on startup is generally associated with glow plug issues. Not saying that the ECT sensor doesn't need to be replaced, but I can't imagine a bad ECT sensor causing hard starts. Think about it... the coolant temperature reading when it's really cold outside can get pretty low, but cold coolant doesn't make starting your engine harder than if it's hot.

Also, the fuel pressure he's talking about is the HPOP IPR pressure, not your fuel pressure. A fuel pressure regulator will not cure that one at all. Your fuel pressure only runs about 60-72 psig with a clean fuel filter, and is located on the driver side of the fuel filter housing in the valley of your engine.

The regulator you need (maybe) is an Injector Pressure Regulator, part number is F81Z-9C968-AB. Tousley Ford has them for $175, but you might be able to find a new one on eBay anywhere from $125-$150. A local dealer will charge you anywhere from $265 to $325. This regulator is located in the rear of your HPOP, and is identified on the pic in post #2 as the IPR... when looking at the black lid on top the fuel filter housing, the IPR is at about 2 o'clock and has a brassy/bronze color. Not too hard to change yourself, but you need a special deep well socket to get it out once you remove the tin nut that holds the magnetic coil in place around the IPR body.

Standard deep well sockets are not deep enough to both fit over the length of the IPR AND allow the square drive from the ratchet to fit inside the socket head. When I replaced my IPR, I believe the socket I found which was deep enough was called an "axle nut socket". [6-point, 29mm or 1-1/8" socket]. Alternatively, if you can get a socket which has a hex drive on the outside of the ratchet drive end, you can use a common length deep well socket and an open end wrench to turn the socket on the hex end (see the pic in this link to see the kind of hex end I'm talking about... 29mm deep well socket image by bossmonkie on Photobucket).

HOWEVER... before you go out and buy one of these IPR's check the tin nut on the back side of the IPR to make sure that it is tight. A loose IPR nut can cause erratic running conditions just as well as a bad/stuck IPR can.

Hope this helps you NOT spend money on something you really don't need and end up chasing down the trouble with more and more parts.

 

Ok what im replacing is the IPR according to the photo diagram that was posted on here. Is that it.? And is there any other coolant sensor other than the one on the water pump that controls the gauge?

 

Correct... Injector Pressure Regulator, Ford part number F81Z-9C968-AB. If you can let the truck sit idle for several days, I would order from Tousley Ford. Here is a link to their web site and parts page for the IPR.

(http://tousleyfordparts.com/parts/20...icleid=1385445)

If you have to have the truck right away, I would go to the local dealer counter and tell them that you have the price from Tousley (print it off the web site), and ask them to match it. They will generally come down to within about $20 of your online price, and if they don't, try another local Ford dealer. I've not had one yet turn me down. They would not do a direct price match, but they have come close enough for me to justify getting it "today", and in this case, you'll probably save about $60-$70 which is certainly worth carrying a printed page and asking for the discount.

The only other coolant sensor you might have is IF you have an aftermarket coolant temperature gauge, but it sounds like the one you need to worry about is the one shown in the picture on top of the water pump, located between the thermostat housing and the heater supply port. If you don't have an aftermarket coolant temperature gauge, then the one in the pic is the only one you have to worry about.

 

One mistake in the photo above is near the bottom of the page. What is labelled as the HPOP is actually the HPOP Reservoir which sits on top of the HPOP.

 

Glad to see my old photo is still around, even if my truck is not. And yes Pete that is the resevior, but it was more of an oversite than mistake....

 

It's around Barry because it was a good photo, no sense in reinventing the wheel, easy for newbies to understand.

And yes technically it is simply the reservoir but if someone is questioning that, they likely know what the sensors are IMO.

 

Ok i love my ford but im ready to set a match to it. I replaced the IPR and the coolant tept sensor. It runs worst. This am it started fine with the engine light on. Ran like crap no power. I will get the codes read again in the morning. I hope something works out i cant afford it much more. The scan is 45$ a pop. The strange thing is this. Before whent the light was on it ran smoth but no power. Whe the light went off it ran bad but had power. Today it just ran bad but had power with light on, no power with light off. ???????? Sorry to keep bothering yall, just broke and work two jobs for the bills and need another for the truck.