Can't seem to kill P1118 and/or P1117...

[Longtallsally]

I have learned a HUGE amount in my first couple of months of Disco ownership. Honestly, if I knew now what I didn't back when, I'd have bought one a LONG time ago. Jeez, these things are THAT bad- and really are relatively easy to diagnose and work on it seems.

Anyway, I was lazy and had GBR do "option B" to kill the amigos recently and also had them remove butt connectors and solder the wires in for the lower temp sensor at the same time in order to kill the last code (reduce resistance values from the butt connectors). It did for a bit, but in my initial drive, I got P1117 come back. P1118 came on once, but when I cleared it, a short bit later, P1117 came back and seems to be sticking around.

In some research, the only appreciable solution I found was to pull the connectors at both the intake and the radiator and clean and slather dielectric grease on them. The guys at GBR think it might be a mismatch of sensors and that the one at the radiator and the intake might not be playing well together. They did confirm no chafing in the harness and that the connections are all good at the radiator end.

Recently done:
- 180F thermostat
- temp sensor at the radiator (the lower one on the passenger side)
- full flush and fill with 50/50 green stuff

Other variables include that the engine has been swapped and I'd say the upper sensor was never replaced.

I'm thinking about just getting the upper sensor as a matter of course and going from there.

What do you guys think?

 

[KyleT]

I'm guessing a D2 with secondary air? A California truck.

The rave has a pretty good breakdown of troubleshooting.

I would just unplug the radiator sensor and see what it does. P1118 leads me to think the sensor is just bad.

 

[Longtallsally]

Yep, it has SAI. The engine has been replaced and the general thought is that when they pulled it from the donor vehicle, the lower sensor was broken off, or torn off- thus the new wire and butt connectors. That's been resolved. The manual is pretty straightforward as there aren't that many components that could fail. The sensor in the radiator and the radiator itself are brand new and the only remaining one not been replaced is the one on the intake. The gauge is reading as normal as it can, though.

This is why the guys at Great Basin Rovers are stumped too. Tom said he read something about there being a possible mismatch between the sensors that could be throwing the code. I can buy this based on the motor swap.

In a couple more short drives, I'm only getting P1117 now. Based on some more research, it could also denote a low coolant condition. In other words I didn't bleed correctly. My temps- once up to operating level- go from 194-195.4 and spike every now and then to 197 and even hit 199 a couple times. There is no rhyme or reason to these spikes (idle, freeway speed, low speed), so I'm thinking I have a couple bubbles still in there, but as temps aren't climbing too much, I'm not getting riled up about that one.

It kinda leaves me to think I'll just spend the $20 and get the new sensor on the manifold, do the cleaning/dielectric grease bit and go from there. I dunno what else I could do?