Car not running in 100+ degree temps?
 

I have had two different engines and they both have had the same issues. When it was 107 in Missouri this year and a couple years ago, my car would just die and not start back up until it sat for a couple of minutes. What would be causing this issue and what is the solution. I am wanting to upgrade to the RE water pump. I don't know that it will even help with this issue. Has anyone else had this issue with their 8. Also, this time when it happened my car had different coils and spark plugs and a new radiator and a new maf.

Umm... Bump!!!

Hot starts are indicative of a loss of compression. It could also be heat soak if the engine is overheating. It's been discussed a million times.


I thought your engine had a faulty coolant seal?

If I remove ambient temp from the equation, there is only 1 failure method that I am aware of that would just make the 8 shut off, but allow it to restart normally some time later. That fault is fuel pump failure due to overheating. The fuel should be keeping it cool enough, even under high ambient temps, but it's possible that this is what is happening for you.

9k, hot start trouble from compression wouldn't make the car just shut off suddenly. Though hot ambient temps could keep the engine hotter longer after shut down and extend the length of time that it can be called a "hot start".

My coolant seal is bad, this was before this happened. It happened to me on vacation to my hometown. It was okay and started kinda puttering a little more and then a little more and then it just died at a red light. This isn't the first time this has happened. I just wanted to know what might be the cause. I have my engine and radiator out ATM and if it was something I could fix then I was going to at this point. I am getting an engine from Mazda for $2001 and it takes 2-3 days for shipment. I don't have this money yet as I am waiting for all my grants and stuff from school. Is there a solution to this issue? And are there any other theories? It seems to be at least 104 for this to happen and only in town driving. Also the temperature as far as the water temp gauge isn't hot or anything.

Puttering as it fails is different from just 'shutting off'.

Keep in mind what all has to happen for the engine to be running. You need spark, air, fuel, and compression. If you miss one, the engine doesn't run. But how it doesn't run, or how it stalls / stops running can point to what. For example, loss of ignition or fuel is typically an abrupt shut-off. If it stays shut off and won't refire, then it's usually because it still can't get whichever one went missing (such as running out of fuel). You have 4 plugs, wires, coils, 1 alternator, 1 battery. If you lose ignition on just one of those, it reacts differently than all 4 at once. If it's all 4 at once, then it's "upstream" from the coils. If it dies slowly, then usually it has ignition and fuel, but either can't get the signals and timing of each right, can't get the proper amount of air, can't figure out how much air there is actually available, or it's just that the combustion aren't enough to keep the engine going.



All that being said, if you had a coolant seal failure, you were likely down on compression anyway, and this caused further issues. You are getting a replacement engine from Mazda that will likely solve this problem. If it doesn't, then it's not compression and you start looking to ignition or fuel.

It won't fix the problem. I messed this engine up due to blown radiator hose and an attempt to make it back home. Its okay I had a bad oil leak anyway. So flame if you want, but I got what I wanted. Now I can keep a clean engine bay again!! The compression was fine before I melted the seal. and keep in mind this happened to 2 different engines 110,000 miles apart with 2 different mafs and different coils and plugs, and probably a few other parts I am forgetting. Probably that damn K&N v1 short ram air kit this kid had on this car when I bought it is causing all the issues. This happened in July also, I am just now posting as I was thinking about the issue.

Well, there you go. If it's not any of the parts listed, and it's not the parts that changed, then it's either something wrong with the MAF (hot air is thin air) that can't read it right (which may or may not be the MAF's fault), or it's something wrong with the fuel system.

I knew what he meant :) Eventually when you have a faulty coolant seal the car will heat soak quickly and suddenly shut off and then not start until it has a chance to cool off. I'm not sure if that is a fail safe feature or a nature of the condition.

Also, a coolant seal typically doesn't "just go" (or if it does it is from a failure of a hose or a major loss of coolant like you said), it starts small and gets worse and worse over time.

Well, hopefully a brand new engine and water pump and radiator and flywheel will fix this..

Note: I know that a flywheel has absolutely nothing to do with this topic, but the new engine comes with one!!!

Just to be clear, It's not a new engine or a new flywheel. It's a cobbled together reman engine made up of some new parts and used parts from someone else s failed motor.

9k, I hear those are typically fantastic, better than the factory motors. I mean your's has lasted essentially forever!

It's like buying clothes off the mannequin at Goodwill. Always a win

9K, I knew this, but essentially it is a new engine. It is reman'd so the housings are lapped and the apex seals are new and the compression is tested. The flywheels are surfaced and flat. Remanufactured to me usually means better. I used to work for HP and our Remanufactured laptops actually went through more rigorous testing versus the new ones. I would rather have a remanufactured one when compared to a new one.

just because someone points out that your actions are dumb does not mean they are flaming you, it can actually be true ...

Ummm, no................................... research is your friend.

Coupla variables here, Justin, that make your comparison invalid. Or, maybe, the comparison is valid but the broad manner is not.

So I'm just getting everyone's crap that didn't work to begin with?

Sort of. But you may get lucky, my second reman lasted 75,000 miles.

Why only 75,000 miles?

Reman's have inferior seal tolerances compared to new factory motors. New factory motors have inferior seal tolerances compared to hand-built quality motors.

Seal tolerances matter quite a bit with these engines.

Among other issues. The actual level of wear on the reused parts could be "within spec" but not far from being "not within spec", etc...

for the record, all rotary engines are hand build, reman or new factory or custom ;)

only difference is, a reman engine will have some used parts. Most likely the e shaft and both rotors. Im not sure if they even check the rotor's groove at the reman plant. It might be not in spec, meaning it kinda "weeee" out, which might give u crappy compression. And the rotor gear might not be secured, etc.

But from what we heard and saw, mazda reman will get you 100% new rotor housing and sometimes iron. Thats really a bargain at around 2k plus the core.

If its me, i will buy a reman, when i get it i will just open it and check everything carefully, if something isnt right, bring it back right away and ask for another one. If its ok then put it back together with better coolant seals like the one from pineapple racing, its really viton seals. They can take abuse(heat) better than mazda's sandwich telfon-rubber-telfon seals, and most of the time its reusable, while the mazda ones will will havemto be replced every single time.

The rotor housings are not new. Not sure if anything has changed since sleepy-z had to leave.

Lets take Hellelrode back to the beginning, since he's getting a bit jumpy at everyone's responses, even though no one is actually picking on him yet.

Hesselrode,

You said that you had two different engines give you issues staying running when the temp was high, and the vehicles were hot.

You also said that during that time, you had changed things like the coils, radiator, and MAF sensor. You also said that the engine had an internal cooling leak, that eventually lead to massive coolant loss.

Well, lets look at the common themes:

Your engine ran hot.
Something caused an internal engine cooling seal to deteriorate.
The same problem happened to two different engines in the same car.
You changed the radiator, but it didn't resolve the hot running issues.

So, lets go back, and see what can cause the car to run too hot that is independent of the actual engine.

Fuel system problems is #1 on the list.

Now, lets look at the different parts of the fuel system:

Fuel Pump
Fuel Injectors

If the fuel pump only partially works, that can lead to the very issues that you are describing, and would happen no matter how many different engines you install in the car.

If there isn't enough fuel being provided by the pump at certain rpms, and you drive in that rpm range a lot, you will run the engine lean. Running the engine lean means that more heat is produced. More heat in the rotor housings can lead to the coolant seal failure that you had. That leads to dead engine.

This was mentioned early in this thread by RIWWP, but you seemed to completely ignore it. He pointed this out to you, and you walked right past it.

Another possibility is a failed fuel injector.
These stay with the engine even after you get an engine replacement.
Same method of failure as mentioned above with the fuel pump, but might be restricted to just one rotor.

So, you might want to look at the fuel system more closely before you shell out yet more money on a third engine, otherwise, the exact same failure will occur.

And I think you know you don't want that to happen again, now do you?

BC.

Okay lets start all over.

This has nothing to do with a coolant leak.. period. I over heated my engine a couple of weeks ago. That is why I leak coolant. Last July and 2 July's before that my car has died on the side of the road, but not before running like shit first and it got worse and worse until it died. I am posting a question about an issue that I have had in the past, not the present. About the fuel. Would it only be doing this in 102 degree weather? Why would it only do this at those temperatures. It isn't the fuel injectors either, cause when I replaced the engine it came with LIM and UIM. And just in case you didn't read. My bad engine has nothing to do with the issue, I f'd up my engine by overheating it due to a blown radiator hose. And according to the temp gauge the temps were normal, I know this doesn't mean anything but just stating all the facts.