QuestionThis is a non-turbo engine, manual. Radiator, fan, water pump, thermostat (now removed) all replaced within the last 6 months.
Under the hood:
1- The coolant has since spewed out from overheating and is essentially water now.
2- "Coolant" and steam is coming out of the overflow tube and under the pressure cap since I plugged the hole in the overflow lid
3- I've disengaged the A/C compressor (via relay) and have BOTH fans on, in tandem, by turning on the A/C- they operate normally otherwise
4- I've run water thru the radiator and engine to flush and check for free flow of water, which it appears to have.
5- Noticed vacuum hose running from the assembly that houses the thermometer..these are disconnected (Goes to EGR, etc) though I've tried to connect them (the 2-way connector is busted short) I can't imagine these causing thermal problems.
The Test:
This car will idle all day long with A/C running and temp stays in the middle of the range - fan kicks on/off normally. I've driven at least 3 miles at a max. of 35 mph to test it (uphill even in 2nd gear) - no problems.
So than I took it for another test--a 10 mile run @ around 45 mph. This is when the temp increased to the point it nearly hits the red line..of course I was 10 miles away from home so I had to shut it off for a couple minutes. When I restarted it, temps were still above normal, however rev'ing the engine to 6000rpm once dropped the temp considerably (rev'ing engine afterwards did nothing); albeit for a minute or so before temps went back up.
So, < 35 mph a okay...cruising speed on the freeway/interstate - its toast...
Thanks for any input
AnswerJustin,
First off, don't block the hole in the overflow lid. If too much pressure builds, it can wear down and possibly blow our head gasket. And that's even more money and problems.
If you're sure you're getting adequate coolant flow, my guess would be you're lacking in oil flow. Your oil pressure may be too low, your oil level may be too low, or there is a blockage some where, preventing adequate lubrication. Not only does oil lubricate parts, it acts as a "coolant" as well. The oil takes heat away from engine parts and prevents heats through lubrication. I had the experience where all my oil drained out, and that caused my engine to overheat and boil out all the coolant.
But it's possible your thermostat is still the problem. I've had friends that installed 2 bad thermostats in a row and caused the same problem you're experiencing. When you mentioned you were able to rev your engine to 6k rpms, engine temp went down, then the temp went back up, that shows there was a lack of flow somewhere in your coolant system. The higher RPMs probably increased coolant flow to normally cool your engine temporarily. Many times that is caused by a faulty thermostat. You may also have air trapped in your coolant lines. Turn your heat on HIGH to allow full flow of coolant into your heater core, and follow the procedure to "burp" your coolant system free of any and all air bubbles.
You can also try to run an anti-freeze/water concentration that is 30% anti-freeze and 70% water. That may help keep your engine cool enough until you can figure out exactly what's wrong.
Good luck!
