Does anyone know what this plug/sensor this is?

[Deville]

Can someone tell me what type of sensor this plug goes too? When ever I touch it while the engine is running it causes the motor to stumble & sputter. I'd like to replace whatever it is, but before I go messing with anything that might cause the truck to not run at all I wanna know what it is first before I take it out so I can have a replacement ready to go.

It's located on the driver side on the motor.

Thanks.

 

[greg334]

Fuel pressure sensor, maybe?

Hard to tell

before you think of replacing it, check the wiring and the connection. You may have to degrease it with contact cleaner and then put some proper dielectric grease to seal it.

 

[Deville]

I for got to add, its a 2000 FL80 CAT 3126. I don't wanna mess with it too much before I know what it does.

U may be one to somthing, cause the truck was near impossible to start this morning, it sounded like it wasn't getting fuel, but the system was fully primed.

Once it's started & running for a few minutes it will start up over & over again.

 

[greg334]

I had a similar problem, it turned out to be the wiring for the fuel pressure sensor. There is an issue with the connector boot leaking and I have to clean it every year, if I don't I can cut the tie wrap, move it and the engine seriously stumbles,

 

[Deville]

Ok, so what should I do?? I don't wanna mess with it to the point that the truck won't run, what do u sugguest?

 

[greg334]

I would take the plug off the sensor and see if it is full of crud or damp, I would then clean it with contact cleaner and put some proper grease back in. I don't have the name of either the grease or cleaner with me, it is sitting at the shop and I am 2000 miles away.

 

[Deville]

ok, thank u! I will try it.

 

[Bruno]

That sensor goes to your glow plug/block heater. That is why you may have had a hard time getting it started. Can you tell me where it goes?

 

[Bruno]

If you have a Freightliner you can check to see if you have any flash codes. The flash codes can tell you if you have a bad sensor or what is causing the truck to not start normal.

 

[Deville]

I have 73, 31 & 39, I know one is the IAC I forgot what the other ones where.

I believe the Hard start was coming from the diesel I was using. For the past couple of years I've been getting the fuel at a no name truck stop on rt 9 in NJ. They were using Shell, but They aren't anymoe, I have no idea what they are using now. So I started using Sunoco & Hess & the truck is starting pretty much on the 1st try now. But I will keep watching it.

When the I touch that sensor when the trucks running, it stumbles & almost stalls. I think it goes into the side of the block towards the front of the motor. I haven't wanted to play with it to much becuase I don't wanna disable the truck with out 100% knowing what it does or how to fix it. I will poke around a little more as gently as possible & take more pics.