Hey all. So bare with me here as I explain my issues, I'm new to this so still have lots of learning to do. I have an 88 accord 4dr lxi FI, and the temperature gauge doesn't work on the dash. I've had it for about 8 months now, and it hasn't worked since I bought it. I just recently decided to try and figure out what the issue is. Well in looking today, I found that the wiring was disconnected from the temperature gauge sending unit, so I reconnected it. Still no dice. Also, in looking at the 86-89 accord sedan shop manual, I see where the tw sensor is. In my car, there appears to be 2 (or at least I'm pretty sure they are both tw sensors). One has a yellow wiring connector and it appears to only be one wire, and the other has a green wiring connector which has 2 wires. On the green connector, I noticed one of the wires is cut from the connector, so obviously this wouldn't be working. Would this cause my temperature gauge to not work? I get pretty poor gas mileage for it being a honda, and on my own research I found that the tw sensor can cause poor gas mileage. Can it also cause poor performance, like slow acceleration all the time? What kinds of tests can i perform to figure out where exactly my issues are, and what needs to be replaced? I do have an ohmmeter I can use for testing, but I'm not exactly sure where the best spot to connect the black ground wire to is when using it. Thanks for all the help, appreciated.

Oh also, my gas gauge works fine, it's just the temp gauge that doesn't work at all.

 

I didn't find a good picture of the water temperature sensors, the parts drawings for 88 seem to be arranged very differently...?

Normally (until about 2003) Honda uses a 1-wire sender for the temperature gauge in the cluster. Maybe the sender is bad? Maybe a break in the wiring back to the cluster?

Have someone turn the key ON & watch the gauge. Take that single wire & short it to ground. The gauge should begin rising. As soon as it begins rising, take the wire OFF of ground - DON'T let the gauge get all the way to the top.

The 2-wire sensor measures water temperature for the FI system. Having that disconnected can cause your bad MPG. But those 2 systems (gauge & FI) don't share information between them.