The other day I went to check the oil in my 85, stock 4 cylinder. When I lifted the dip stick out, there were wisps of smoke, and the oil was very hot. I've never experienced that in my other vehicles when checking the oil. It's always been warm, but not as hot as this. Is this something to be concerned about? I changed the oil about 900 miles ago. I did accidentally put in 10W-40. Could that be an issue?

Thanks.

Hard to say, without more information. I would swap back to 5w30, for this time of year, but I don't think that really is an issue. The "smoke" could have been water vapor. What is your coolant temp at?

If the temp gauge is accurate, it's only reading about 1/4 of the way. I don't know what temp that division of the gauge is reflecting. I do know that if the coolant isn't circulating, it is rising, and when I'm moving again, it drops back down to around 1/4.

The oil pressure is reading about 3/4 of the way, and it doesn't fluctuating when driving. I don't notice any changes in performance.

Is there more information I can provide that might diagnose the issue?

I can't answer the question of how many degrees is normal for the oil but if you used one of those laser thermometers and pointed it at the oil pan on the Fiero and then pointed it at other warmed up cars oil pans you could get an idea if it's running hotter than other cars. I know that the thickness of other oil pans, if the other cars have oil coolers on them along with other cars being newer may alter the degrees but this may give you some kind of base line to look at to see if it's abnormally hotter than other cars. Just an idea. Not sure if it will work or not but may give you some kind of average without having to take anything apart.

I've experioenced the hot oil and wisps of what may seem like smoke it shouldn't be anything wrong. Probably just the oil on the dipstick hitting the hot dipstick tube while you pulled the stick out, even the inside of the tube. When you turn the car off parts the engine can heat up hotter than running temp for a short while because air oil and coolant are no longer being circulated.

With the info above it seems like everything is OK. Engine temp will increase slightly when using higher (thicker) viscosity oil, i.e. 10-40w or 20-50w vrs 5-30w, if no additional cooling is added. Keep a close eye on everything for awhile until your convinced that a problem isn't brewing.

Let us know if more symptoms develop and maybe we can help if needed, good luck.

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"Because in a split second, It's gone"
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