it’ll peg out if you let it keep going.

I drove it to work for the first time in probably 6 months today(winter, broken leg, covid). Got to work and just let it idle. Took probably 5 minutes to start creeping up. Got a little over the halfway point and I popped the hood and the fans were on.

gonna look in my parts bin and see if I have a thermostat for it. I’m sure I bought one I just can’t remember if I put it in or not.

 

Bleeding air out from the thermostat housing, but I'm sure you know about that. I can usually tell if there's air in the cooling system by squeezing the top radiator hose when the engine is cold. You can hear & feel sloshing if there's any substantial air pocket.

But since the temperature stays OK when the car is moving, that seems to say your T-stat, waterpump, and radiator are OK. I figured the overheating while idling was from the fans not actually running.

Got anything around the fans that might obstruct air flow? But again, why would that not block air flow when you're driving...

 

hope to put a new thermostat in this weekend.

haven’t driven the car since the last post. I have only tried bleeding the system once after the new radiator. I tried it a few times last year.

it’s certainly weird. I’d love to get the car going again since my daily commute is about 50 miles and my v10 gets 10mpg.

Temp also drops super fast once you start moving. Like within 100ft even at slow speeds the gauge starts dropping quick.

nothing is obstructing the fans, it’s a stock set up. Don’t see any visual damage on the fans and seem to spin at normal speed.

 

Put a new thermostat in and seemed to stop the overheating. Took it for a ride then let it sit and idle for 10min or so and temp gauge didn’t move. Now just need to figure out it’s high idle. Will idle fine when it’s cold but sometimes not always will idle high when it’s hot. Gonna clean the iacv and see if that does anything for it.

 

I think that year also has an FITV for fast-idle when the engine's cold.

 

Yup, 97 is the last year for the FITV.

 

Well the plot thickens. I cleaned that and it seemed to make things better. Not perfect but better. Highest it would idle would be 1,400 or so. Put 15 miles on it or so then stopped to get gas. Fired it back up and it was misfiring and throwing a code for cyl 2 misfire. evened our pretty quick but then idled at 3k rpm again.

I cleared the code and idle got better but was more like 1500-1800. And even Surged at times.

got it home and decided to pull the plugs to see. Plugs looked good but all the tubes were filled with oil. Cleaned them all up and checked the valve cover and it was all really loose. Tightened them. Started it back up and it misfires now but doesn’t throw a code and it doesn’t even out. But even more concerning is now the oil light is on. Checked and it has plenty of oil. Even added some and it doesn’t go away. Probably gonna try new plugs and wires now. But not sure about the oil light. I mean it is running really rough. Probably from all the oil that leaked in the cylinders when I pulled the plugs.

checked the tubes after tightening the valve cover and it didn’t seem to gain anymore oil.

 

Took the plugs all out again and cleaned them. Doesn’t misfire anymore. And the tubes seemed to stay dry. But the oil light is still on. Just seems crazy that either the pump or pressure sending unit would just happen to go out.

 

Much more likely for the oil-pressure switch to go bad. I've even seen threads where they leak through the switch body...

 

Yup, my Toyota did that about 11 or 12 years ago. Checked everything over, and then replaced the switch. It's been good to go since.