Hi, is that plug supposed to be plugged into something? Looks like it's there for a reason?? Thanks.
or dummy plug ?
Temp sensor
- Thread starter jpjeep26uk
- Start date
Flyer58
YJ Addict
The fuel injected 2.5 uses that type thermostat cover with a temp probe. I'm not sure if the carbureted engine uses it so it's probably just plugged.
Hi, mine is a 2.5 fuel injected. But I can't see any obvious cable or wiring to plug into the sensor. Seems odd to have a real sensor plugged in but no wiring connected. Totally confused now haha.
Flyer58
YJ Addict
There should be two sensors. The front one in your post goes to the ECM computer. The rear one at the back of the head goes to the gauge cluster in the dash.
Is your engine running ok and does the temp gauge work?
Hi, the engine ran fine for months since i bought it but has recently developed a mighty backfire after having the alternator belt replaced. Part of my investigations in the engine bay brought this thing to my attention. So as the car ran fine before I found it I'll say yes, no issues with the engine and the dial works fine. I don't even know if my YJ has an ECU. It's a Sept 1988 with fuel injection built in Ontario if that helps?
Flyer58
YJ Addict
Ok throttle body injection? This is getting outside my line of knowledge which is limited to my '92 2.5L. I think the ECU might be under the dash. If it's fuel injected I believe there should be a coolant temp sensor and typically that's the one in the front like your picture shows.
I found this wiring diagram in the Factory Service Manual which shows the sensor in the 1990 model.
Link in our Reference section of this forum... https://wrangleryjforum.com/attachments/1990-jeep-wrangler-yj-service-manual-pdf.115624/
Hi, yeah, TBI that's right. I'll check under the dash for an ECU. It's a mess under there. Tons of wiring and all of it old and hacked into and piggypacked etc, probably needs overhauling! I'll take a look and see if anything is un hooked or loose etc. Thanks for the diag.