mpath

Yesterday I drove from Vancouver to Seattle for the Seahawks game. The last hour or so was in bumper to bumper traffic @ low 90's ambient temperature. Oil temp gauge creeped up to 250, and coolant creep up to the first hash mark past 175. I did turn off AC, but at one point the dash warning light went on for a second sarying not enough oil pressure. I couldn't exit the hwy immediately to stop and cool the car down, but by the time I could, coolant closer to 175 and oil around 240.

After the game car started just fine, and drove back with all gauges normal. What should I check/replace, or just typical hot weather conditions?

BTW, car is 06 C4S, I did oil/filter change just last weekend, and oil level is correct.

Linnm

Sounds weird but when it is very hot turn on the car heater to help drop the temp. Makes you a little more uncomfortable but might help cool the car

tomc_mets

I routinely drive in 100+ here in Texas and have never seen it get that high. 220 F perhaps the highest. I'd definitely have it checked out if it occurs again...T

Racetwin2

Problems with the radiator fans? Could you hear them running on each side at the front? Also at the rear?

Or just have it checked without speculating further

Philster

Oil temps should be lowest when puttering in traffic, no matter whether it's 80 or 100 deg F. Problem: Fluid ain't flowing to cool the engine or radiators are jacked up. Get on it.

You have a cooling problem and should get it addressed before driving again. Your 'low oil pressure' warning is because you're oil is too thin and your engine was too hot, making it thinner.

I'd say you have an oil change and cooling diagnostic in your future. Modern cars do NOT take well to overheating. Overheating events shorten the life substantially. They are potentially catastrophic events.

Macster

No way to measure oil temp with my car but coolant temperature can sometimes get quite elevated in traffic. I would therefore expect oil temperature to likewise be elevated.

Macster

What oil did you use? Check that. If you live in Vancouver you probably should use 0w-40 to ensure winter cold starts are uneventful.

What might have happened is at some point the radiator fans and engine compartment fan call came on at the same time and the engine idle speed can take a momentary dip and if the engine and oil is very hot as it was in this case the oil pressure can take a momentary dip.

Fortunately at idle the engine has a pretty minimal oil pressure requirement so no harm was done.

I am kind of surprised that the engine RPM didn't get elevated. On a hot day (90's) driving up 50 highway to Lake Tahoe I got caught -- in my Turbo -- in stop/go traffic and at one point I noticed the engine idle speed was around 1K vs. the approx. 750 it normally is. I believe the DME sped up the engine to increase coolant circulation and maybe to boost electrical output as the radiator fans and engine compartment fan were on almost full time.

Be sure the oil level hot is correct. I like to run the oil level in my cars -- hot -- at the max line level.

Be sure the radiator ducts are free of trash. I have found trash build up doesn't affect cooling but just to be safe be sure these are free of trash.

Check both radiator fan motors run and both fans blow the same amount of air and at the same temperature. In my Turbo I had a radiator fan motor shaft snap and while the motor ran the fan didn't turn. Might mention that even though one fan was not running the engine never showed any signs of running hotter even in 90F+ Fresno CA summer temps and this with the A/C on, too. What clued me in was the fan noise was different -- diminished -- from what it usually was and I got out and checked and found no air coming from out of the passenger side radiator duct exhaust outlet.

Another time while the driver side fan motor was running and the fan turning the amount of air being blown out the back was way less than the passenger side. The tech checked and found not fan stage errors but found the driver side fan motor was drawing a lot more current so I had him replace the fan motor. Afterwards both sides blew the same amount of hot air.

kellen

What's the upper limit on the oil temp for these vehicles? Mine will hit a little above the 225 with spirited driving in hot weather, around 240. Not common but does bump up every now and then.

Live in same climate as OP.

mpath

Thanks guys. I will get it checked out. All fans front/rear are working, and this was the first time I've seen the coolant temp budge ever from 175, and until yesterday, never seen oil temp go pass 220ish.

@philster - I've read the various threads on alternative brand/weight of oils here, but currently using Mobil 1 0/40 as recommended by my dealer for the Pacific Northwest.

Speaking of engine overheating, I owned for over a decade a BMW with the M82 V8, and its Achilles heel was the cooling system. That thing was insufferable when it was bad, but smooth as silk otherwise.

mpath

Just saw this as I was typing.

Oil is 0w-40. Idle stayed normal throughout the bumper to bumbper grind. With all the traffic noise, it's hard to say if all the fans were working, but it was this morning when I started it in my garage. But i will have the fans checked out. Also, I'm a stickler to keeping the front intakes clear of debris. I'll check the oil level with it hot.

Philster

To cool down the oil and the coolant you run at idle or fast idle. It's puttering along that should see cool oil temps... and when they climb, that's a sign of a problem if they climb very high and cause warnings to pop up (Alert: Son, your oil is so roasted, it's now 250 and too thin to protect the engine. Probably a better warning message than stock)

250 is high for puttering along. People hit the track on hot days and run those temps, with the engine under load (which builds heat like nothing else).

How to you cool down the temps and oil? Drop the RPM, idle, fast idle, etc. That's the actual cool down routine per Porsche: Idle... or fast idle.

It's been blistering here in the NE of the USA. 220 in bumper to bumper shore traffic pushing 100 degree air temps and oppressive humidity. Pure hell. The kind of hell where you try to stay in gear, but traffic inches -- literally -- and you can cut the ozone with a knife. I've hit that after running hard for two hours, with the engine well heat soaked. 225 was just sniffed. Oil pressure: Above the 1 line.

I don't know how you drive... whether you're a clutch slipper, a clutch burner or dog the mechanicals just to creep along, but you're running very hot and have super thin oil.

Forget one thing... or two... just look at the whole picture... and say you have a cooling problem somewhere or incredibly bad driving habits.

.

911Finally

mpath, hope all goes well but definitely should get it checked. But on another note..... GOVIKESGO!!!!!!!!!

mreloc

Actually I see coolest oil temps at highway speed (typically under 200). Puttering along bumper to bumper drives oil temps up to 210ish for me. LA 80 degree weather. There's a balance of airflow/engine strain that results in the optimum.

motopix

I'd be a bit concerned that your water temp meter actually moved. I've monitored mine with a scangauge and it goes up to about 197 before all the fans kick in and bring the temps down. But the car's temp gauge never moved.

I have a 3rd rad installed (had it since I bought) and this year the oil temp has been nudging towards 225 with a bit of spirited driving and oil pressure at hot idle is below 1. Last year, I don't remember getting over 200 oil temp.

I've got a 997.1 with fresh Motul 8100 oil (had the same oil temp increase before the change in this heat) and a new pressure sensor, just fyi.

: edited to clarify

mpath

I appreciate the feedback, thank you. I've made an appointment at the dealer for next week to take a look at the whole thing. Last summer was a lot hotter and oil temp never got this high, and coolant never moved past 175. As for driving habits, I'm easy on the clutch and in all my previous cars, have lasted longer than their recommended life.