Questioni have a 92 mazda miata that i have recently had a lot of problems with. first, about a month ago my car overheated. i took it to a mechanic and they replace the water pump, fixed a leak that was behind the cover, replaced tubes of some sort. the car ran fine after that. about 2 weeks ago, on my way to school, my car felt like it was losing power. then my battery charge light came on. i pulled over. started it back up and it seemed ok but then my car overheated yet again. so i took it back to the mechanic. i guess a belt had snapped. ok, so at first they told me they replace the timing belt, but on receipt it says alternator belt.. i'm so confused.
after that was replaced, the car wouldn't excelerate the way it was and now i'm hearing a pinging noise coming from the engine when i excelerate. the higher i let the rpm's go the less i hear the noise, but the car dosen't seem to go fast any more.
i have been taking the car back and forth to the mechanic's but they keep telling me it's fine. but i know my car. so last week they told me that i could fix it either one of two ways. to take away the noise i would lose power, if i want power i would have to deal with the noise. today i got an oil change. drove it home and it seemed fine. so go to leave again,and as i'm driving down a canyon hill the car starts to lose power, so i turn around to go back uo the hill to go home and i can't get up the hill unless i stay in 2nd gear. 3rd gear wasn't giving me any power.. what could possibly be wrong now???
please help!!!!
AnswerOk - deep breath.
We may be able to save this one.
The alternator and the water pump share the same drive belt. So yes, when the dash lights came on and it overheated it was because this belt failed/broke. When it did the alternator not spinning caused the charge light to come on and the water pump not spinning stopped the flow of engine coolant from flowing to the radiator and back.
Now, as for a Miata. It is likely one of the most problem free cars you could possibly own, it can go for more than 500,000 miles. Now that said, they are man made and as such man made things can break from time to time. Normal maintenance is usually all that is needed along with some preventative work to keep them purring happily and you with it.
Water pumps see internal seal failures (leaks) somewhere around 95-120k. It is a normal replacement item for us at the 120k (or second timing belt service). The timing belt should have been replaced as part of that service since it had to be removed to get the pump out. In addition to that the alternator belt (the one that broke) and the AC belt should have also been replaced, again since they needed to be removed to gain access to the pump. Beyond that three seals a thermostat and a couple of gaskets and o-rings and this machine should have remained problem free in this area for some time. (an added note on the broken belt issue - IF - it was replaced then it was over tightened when installed which may have caused a new belt to fail.)
The two main issues that lead to overheating with Miatas - a leak at the top tank of the radiator (cracked plastic - causes a drop in coolant level), a bad fan motor (restricts/limits the amount of air flow through the radiator - mostly prevalent when stopped in traffic). Did the radiator bust open (cracked top tank) when it overheated? Was it still equipped with the original radiator?, if not was it replaced with a Mazda style plastic tank model or an all metal model (cheap after market).
Overheating is a serious problem, the severity of it can cause severe engine damage which normally is seen within the cylinder head area first then the lower engine. When you experienced the first overheat, did you catch it quickly and stop the engine? Did it ever shut itself off? What was the highest mark the gauge displayed. On that note - NEVER run a Miata when the temperature gauge passes the half way mark on the gauge - better to stop and wait for it to cool down than to kill it on the road dead trying to make it home. If it won't go then stop in a safe location and call a wrecker.
I have seen many go to a severe overheat point and survive with no ill effects so you could be okay but more information is needed for me to help you with that.
Pinging with power loss is not normal and is a sign of a problem do not let it ping. It can be caused by several things.
a. Low grade gasoline with incorrect ignition timing (which should have been set when the timing belt was done)(this would be my first step - run premium gas for now and get the ignition timing setting checked)
b. An exhaust restriction (normally at the catalytic converter) could cause the engine to be unable to breathe properly (a distinct hiss is normally heard from the tailpipe). An overheated engine could cause a converter to fail and vice versa a failing converter can also be the cause of overheating in the engine by restricting the exhaust flow.
c. Lastly and the worst case scenario - since it overheated it is possible that internal engine damage could be leading to the engines inability to make power, pinging or a rattling (diesel engine sound) under acceleration could be a sign of excessive run out within the cylinder head which may mean a new head, but let's not jump off the ship just yet.
Don't panic, try the suggestions in step (a), answer my questions and I'll hopefully lead you to more happy Miataing miles.
