OK, I havent driven my car for about 2 months. I was on my way to work today and noticed my car said I was running at about 240 degrees(coolant not oil). HMMMMM it was like 38 degrees outside, I started to freak out thinking the temp was going to keep going up. Next thing I know its dropping rapidly and is below normal temp like 165 degrees. I pulled some codes today and got p0420hc and p0430hc. Those were my only active codes. I looked up what they might mean and this is what I found. Catalyst System Low Efficiency Bank 1 and Catalyst System Low Efficiency Bank 2. I got an explanation of why this code could be thrown out and one of the symptoms was temp gauge malfunction, not the gauge itself but the sensor. Another had to do with bad cats and bad voltage to the o2 sensors. Im really hoping that it is a malfunctioning temp gauge sensor and not my engine is getting to hot and going to melt into one solid block.ANY HELP FROM LEE or anyone else is greatly appreciated!

PS: I thought it might be a water pump problem before I pulled the codes. If the water pump is going bad does it throw any codes?


Thanks!
Luke B

 

First of all I doubt it was anything serious. After checking everything I would clear the codes and just watch it. Sounds most like the temp senor went momentarily bad: maybe just cold weather.

If it were my car I would check the coolant level, hoses, etc. sensor wires for anything lose, etc. Remember, with your type of SCr it is really near the radiator and a good deal of that coolant system was removed, re-installed, moved, re-wired, or otherwise disturbed during installation: things are tight under the best of circumstances now and have to be just so -- maybe something got jostled. It could be as simple as a connector that was not quite taped tightly when reinstalled.

If, after checking, you can't find anything, I think I would replace the sensor (if its cheap and easy toreplace -- I can't remember where it is or what it costs, otherwise, just leave it). I would make certain it is securely installed and sealed regardless, so moisutre can't get at it. I would re-crimp or otherwise make certain of all the electrical connections. Use electricaltape everywhere to seal, particularly anything that can get road slush on it. I'd conclude that what happened was, somewhere it picked up a tiny bit of moisture which froze during the recent cold, the ice expanded and momentarily broke the electrical connection from the sensor, causing the momentary sensor failure, until engine heat melted and eventually evaporated it, the connection reestablishing itself but just waiting to happen again. Stuff like that has been known to happen.

 

Thanks Lee! There is no coolant or any other leaks on the driveway, I looked at all the connections and my coolant is at the appropriate level. Im going to go with you and say the sensor got messed up by the cold.

 

You may concider the thermostat. If it sticks closed, the enginge temp will climb. When it finally breaks open, the water can now flow, and your temp gauge will read cooler. IMO, change your thermo. Same temp rating.

 

It certainly can't hurt to change the themrostat, and its easy to do and cheap insurance. If it happens once more, I'd do that too.

 

Easy to do by whos standards?Is there any literature on how to do it that you guys know of?

 

Where the top radiator hose goes to the block, that's where the thermo is. Remove two bolts,...uh....1/2" I believe, and the thermo is right there.

 

Thanks! I already purchased a new 160 degree thermo, just waiting for it to come in!

 

A little tip.....
Drain your radiator down to where the water level is below the upper hose outlet. That'll save ya from gettin' a gallon or more of water all over the top of your engine. Now remove the hose from the radiator and bend it down to drain the water in it. Place a few paper towels around the thermo housing, to collect up what little water that is left in the hose, as you remove the thermo housing.

 

Thanks for the tip for the noob.I would have got water all over for sure.