'02 Protege 5 engine overheating issues...

clay_y2k

Member
Help! (attn)

Driving into work a couple of days ago my '02 Protege 5 started overheating. I was driving along and, suddenly, the temp spikes to the "H" level. Then the engine light turns on as well. I also noticed that the engine pinged when applying throttle. I limped into work.

The first thing I noticed when I popped the hood was that the cooland resovoir was at the full mark and coolant sprayed in the engine compartment. I drove straight to the dealership 25 miles away with my fingers. I suffered no engine damage luckily.

I had the Mazda dealership replace the radiator. They assured me that they test drove the car TWICE and there were no issues.

So tonight I'm driving into work and the same thing happens! This time the coolant resovoir was bubbling. Coolant was getting to the engine and back but the engine isn't being sufficiently cooled.

Does anyone know what might be the issue?

Thanks,

Clay
 
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bubbles

air in the hoses or radiator will cause overheating cuz the water really isn't circulating... also will cause back pressure cuz the water pump is unable to push the water pass the air
 
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Make sure you have a good seal on the radiator cap. If it's the original, replace it. That little rubber seal inside the cap is very critical to proper cooling system operation. I'd be surprised if the dealership re-used your original on the new radiator, but then again ? ? I once had a Ford-Mazda dealership break off the radiator inlet (plastic) rather than cut off a stuck hose, and tried to sell me a $600.00 replacement radiator.
Rule out a bad radiator cap, I'd guess they are around $15.00.
 
T-stat maybe? My car would run fine I would drive it like grandma but as soon as I got on it the thing would peg hot. Turns out the spring got weak on the Orig t-stat.

But beings that they put a new rad in it my guess would be air in the system.
 
T-stat maybe? My car would run fine I would drive it like grandma but as soon as I got on it the thing would peg hot. Turns out the spring got weak on the Orig t-stat.

But beings that they put a new rad in it my guess would be air in the system.

+1 for T-Stat. Straight up 5-minute job.
 
Our T-Stats fail in the closed position (notcool) , unlike other designs that fail in the open position. Hopefully you needed that radiator, your original symptoms sound just like when my T-Stat failed ...

* Edit: Welcome!
 
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Overheating Protege5

If you have p5 and it is overheating and symptoms are as follows:
1 doesnt overheat at idle or when driving around slowly
2 overheats at speed or under heavier loads
3 Air conditioner doesnt work when overheated(this is fail safe for the compressor is all i can figure so it doesnt damage the compressor and for motor so it doesnt damage motor trying to run compressor while overheated)
4 Valve clatter( this is one of the first symptoms that should tell you motor is getting hotter then normal; happend to me weeks before car started running hot on gauge)

The culprit is more then likely the thermistat! The spring has gotten worn and even though the thermistat is opening it is opening at a higher temp due to the worn spring and therefore running near overheating on the gauge!

The t-stat is easy to change and varies depending on wheather you have the fs or z motor in your p5(fs motor it is in lower block in lower radiator hose that goes in bottom of radiator; while the z motor is at head in the upper radiator hose that comes from the top of radiator)

one bit of advice that i can give when changing t-stat on the fs motor is be very careful when retightening the bolts to the t-stat housing! they are pretty weak bolts(and they take alot of abuse being heated and cooled repeatedly over the lifetime of the vehicle) Using a standard size rachete i stripped the threads on the bolt itself with relatively little pressure when reassembling the housing to the motor! luckly the bolt backed out easily(i thought i was gonna have to use easy out and rethread block when it first happend) i realized that one more small crank of the rachette would have broken the bolt off in motor as it was cracked and threads were stretched(wheew that was a close call and why i am posting to this thread so be warned) i suggest you purchase 2 new m8 X 1.0 bolts from lowes or the autoparts store before changing the t-stat; take one of the old bolts with you to insure right threading and length is your best bet)

hope this helps someone out there who has similar problems with p5 overheating!
 
Clay, I had the same issues. Coolent overflowing while going to work, the whole nine yards. Goodyear replaced the radiator, the cap and the t-stat. Next day, it overheated again. It was the t-stat, they put on a bad one and once they replaced it the problems stopped.
 
Our T-Stats fail in the closed position (notcool) , unlike other designs that fail in the open position. Hopefully you needed that radiator, your original symptoms sound just like when my T-Stat failed ...

* Edit: Welcome!

My last thermostat failed in the open position
 
Our T-Stats fail in the closed position (notcool) , unlike other designs that fail in the open position. Hopefully you needed that radiator, your original symptoms sound just like when my T-Stat failed ...

* Edit: Welcome!

MOST t-stats fail in closed postion unless its a fail safe one from my
 
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