My buddy got a 96 Pete with a 2ws cat . Temp gage jumping quickly 150 130 150 130 160 130 , engine runs around 150 he assumes if gage is right . video link here https://youtube.com/shorts/tlB7GfMDdfM?si=eWG6S7Mzsgc1KCqw that video is what it’s doing . thanks guys
Check guage, verify with laser check t stat would probably be next, or belts to see if it’s slipping on the water pump
check the wiring at the temp sensor. many times it's just a push on connector and they don't always make good contact. to test wiring and gauge pull the wire off the sensor and the gauge should be all the way left. ground the wire and the gauge should be all the way right. this is if it's a one wire sensor and I could still be wrong.
i thank you are correct. believe there are two sensors right there near the thermostat. one is for the gauge and the other will light the temp light on the dash when grounded.
yeah I can't remember for sure, I think the earlier ones are different. my 6nz had a single wire for the gauge and a plug in one for ecm. for the OP it's pretty common also for the gauge to be off by more than a few degrees also
Find someone with a scangauge to plug in then you'll get the temp that the ecm is seeing. Also I think 150 is probably too cold for normal operating temp