Intermitted Power Loss, Please Help!

I just had an issue car would just turn off while driving it. No symptoms of it happening just bam! Its off. Turns out the crank sensor had chaffed just below the plug against the lifting eyelet causing it to ground out and kill the engine. Took 3 days to find that. Might be a wire worn down near the cam or crank sensors

Sounds to me like a crank shaft position sensor failure?

From my research, the CSPS could also have the same symptoms that my P5 has, except I am unsure about the issue being intermitted. Plus, it seems like weather has an impact on if the problem shows. It warm weather, the car was fine, but the colder it got, the worse the problems were. Also rain had an impact. If it was raining, but not cold, the problem would sometimes show. This is why I thought it could be electrical in nature, such as a short.
 
The part that bugs me is that his car will probably start running fine in a few months when spring comes ??

That to me suggests our fussy coils or maybe the ECT as he suggested... or maybe the IAT sensor ??

I suspected all the things that has been mentioned on all the posts so far except for the IAT sensor.

The weather is suppose to warm up this upcoming week.

I rent a huge garage where I do most of my work, but it is a 25 min drive. If my car makes it there, will swap out all the things mentioned so far, Plugs, Wires, Coils, and maybe the ECT, CSPS, and IAT, and see if that helps.

Thanks everyone for you assistance with this issue.
 
From my research, the CSPS could also have the same symptoms that my P5 has, except I am unsure about the issue being intermitted.

I could see the issue being intermittent of the gap is right on the borderline of being too big.
I would suggest inspecting the gap and electrode for crap before swapping it,.. just for reference sake.

. Plus, it seems like weather has an impact on if the problem shows. It warm weather, the car was fine, but the colder it got, the worse the problems were. Also rain had an impact. If it was raining, but not cold, the problem would sometimes show.

That really sounds like coils !!!
Those fussy dam things !!

If you pop the hood and tell your coils to F-off they will retaliate with a miss-fire !!
I never swear at my coils !! lol
 
My p5 did what your saying yours does I never could figure it out and just dealt with it then one morning my timing belt broke, as I was replacing it I found that the tensioner was bad so I replaced that as well after I got the car back together it ran better than ever no more random stalls or power drops.
 
to answer, yes coils can cause the car to misfire so badly it will eventually throw a code but not immediately. i live on a *very* muddy dirt road. when it rains it turns into a mud bog basically. I have to hit a couple of them at a pretty decent speed or risk getting stuck... when it's really deep (like a foot or more) a considerable amount of water gets where it doesn't belong and the ignition coils and spark plugs are not happy. it usually takes me about a mile down the road of doing this before the MIL comes on (if at all). It misses and stumbles really bad, never had it shut off from it but been pretty close. However, it will eventually clear itself up and run fine a few more miles down the road and a couple days/drive cycles later the MIL turns itself back off. I know what causes it so i don't worry about it, and generally i know it's going to happen before it does
 
I rent a huge garage where I do most of my work, but it is a 25 min drive. If my car makes it there, will swap out all the things mentioned so far...

I think you should swap out your coils at home before your trip to the garage. It takes 5 minutes and it's warmer out now.
If your car makes it the 25 minute journey without problems, you've probably fixed it.
That way you know exactly where the problem was and you don't have to do the other stuff which could create a problem just by messing with them.
(except plugs and wires,.. they're always a good idea)
 
to answer, yes coils can cause the car to misfire so badly it will eventually throw a code but not immediately....

DTC P0300 Random misfire detection
DETECTION CONDITION
PCM monitors CKP sensor input signal interval time. PCM calculates the change of the interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, PCM detects a misfire in the corresponding cylinder. While the engine is running, PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions and calculates misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.



OK,... So what I wanna know is,..

What is that preprogrammed criteria ??
How many misfires are we allowed for 200 revolutions ?? 1000 revolutions ??

Maybe dorkidori can tell me ??
Apparently he's cracked Pandora's Box !!

https://www.mazdas247.com/forum/sho...e-ECM-tuning&p=6557550&highlight=#post6557550
 
DTC P0300 Random misfire detection
DETECTION CONDITION
•PCM monitors CKP sensor input signal interval time. PCM calculates the change of the interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, PCM detects a misfire in the corresponding cylinder. While the engine is running, PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions and calculates misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.



OK,... So what I wanna know is,..

What is that preprogrammed criteria ??
How many misfires are we allowed for 200 revolutions ?? 1000 revolutions ??

Maybe dorkidori can tell me ??
Apparently he's cracked Pandora's Box !!

https://www.mazdas247.com/forum/sho...e-ECM-tuning&p=6557550&highlight=#post6557550

That is a good question. I know when i go through big puddles the car is misfiring BADLY. Like almost undriveable badly. And it usually clears up by the time i get a couple miles down the paved road once i reach pavement. it's 50/50 if i actually get a check engine light or not when it does happen.
 
It seems to allow a lot of misfiring before throwing a code.

You're not even supposed to bump start your car, there's enough unburnt gas going through to burn out your pre-cat.
 
It seems to allow a lot of misfiring before throwing a code.

You're not even supposed to bump start your car, there's enough unburnt gas going through to burn out your pre-cat.

lol I did that quite a bit a couple months ago when i was having battery terminal problems... didn't have the time to change them with my work/travel schedule but luckily parking garages at airports have a pretty steep grade in them :) Never got a code from that either, but my radio wasn't really happy with it. woudl work fine and reboot every 10 minutes or so. Will do it every time i bump start it, but never when i start it with the key. one of those things i guess
 
The weather is suppose to warm up this upcoming week.

I rent a huge garage where I do most of my work, but it is a 25 min drive. If my car makes it there, will swap out all the things mentioned so far, Plugs, Wires, Coils, and maybe the ECT, CSPS, and IAT, and see if that helps.

So what happened ???

Did you get your car fixed ??
 
So what happened ???

Did you get your car fixed ??
Sorry that I haven't replied back yet.
They only think I have done so far, other than the things I mentioned all ready was swapped a coil.

I know a lot of people posted thinking that was the issue I was experiencing, but I had a feeling that it was something else, and sadly, I was correct, as I still have the problem.

It will be warm for the next few days, and I am furloughed at my job, so I plan on putting in new plugs, and swapping out wires with old ones I have. Hopefully it will be that easy, but I am worried that it is something else.

If that doesn't work, I will try to make my way to my garage (25-30 minutes away) and start trying the other things mentioned.
 
My p5 did what your saying yours does I never could figure it out and just dealt with it then one morning my timing belt broke, as I was replacing it I found that the tensioner was bad so I replaced that as well after I got the car back together it ran better than ever no more random stalls or power drops.
I really worried that this is the problem, and I really didn't want to spend the money to get a timing belt kit, plus I have never done a timing belt before, so I am unsure about how that will go.
 
Any updates on this?

Yes, a minor update.

I needed to do the P5's Maryland emission test, which is going to be due soon. I am not worried about passing, as there are no CEL on, but I was worried about getting there and back.

I wanted to do the plugs before I went to rule them out. With the weather being cold again, and my schedule, I didn't get a chance to do it until the day I planned to taking my car for the emissions test.

I got plugs, installed them very quickly, and then attempted to start the motor. Normally, I would do an ECU reset after the plug change, but I could not do that this time due to the test, as it would fail because of the ECU reset.

The motor started, but stalled about 5 second later, I had a hard time to get the motor to turn over after that.

I got it running, and was going to let it warm up (it had been 3ish weeks since the last time I started it), so I went inside for 5 minutes. Came out, and it was stalled. It wouldn't start after that.

I decided at that point to reset the ECU, considering I only had a short time before the test station was going to close.

A short time later, I started it, it ran for 10 seconds, then stalled, I started it again and it ran rough. I noticed that this is common after a ECU reset.

I took it for a short test drive after the motor reached op temp, and it drove perfectly fine. Sometime soon, I will take it for a long test to see if the plugs fixed the issue. I really, really, really hope that this was the issue.
 
Also, let me say a couple things that were said previously, incase someone missed it.

The plugs I recently removed were not old plugs, they had about 1-2k miles on them.
I replaced both coils again in the past few months. The old ones were about a year old.
The problem does not show symptoms until about 5-15 miles of driving. I am able to take short trips with no issues what so ever.


I have a garage that is about 25 minutes from my home, but I ran out of heating oil, and it is crazy cold there. I plan on fixing that soon, and getting the P5 there to do some more tests.

I have given it some thought, and I am probably going to replace the timing belt and tensioner sometime soon.
 
Last edited:
I have another update, and the issue may have been fixed.

Since my last update a few weeks ago, I have not touched my P5 until yesterday.

I just had not had the time, or the weather was bad, so I was not able to test the plug change until last night. The weather was warm, and dry when I first started messing with it.

The P5 started and idled, but stalled after a few minutes of running. I restarted it while keeping the RPMs up a little for about a minute. Then it was fine at idle.


I test drove the P5 for about 10 miles and there was only one tiny loss of power 3 miles in, but not typical of the symptoms that I was having before.

It started to rain, so I stopped at a pizza place, ate a slice, and continued the test drive about 30 minutes later when the rain stopped.


I stayed close to home, but would venture out further and further as I got more confidence in how the P5 performed.

I ended up driving for about 1.5 hours total, and put 55 miles on it since the plug change. 50 of the miles were last night. It rained a few times while driving, and there was not any issues.


I am not sure if it was the plug change, or just the warm weather. I feel comfortable to drive the P5, but not with my baby in it, so I won't use it for commuting and/or dropping the baby off the at the daycare.

I will wait for the cold weather to return and try to get a few more test drives in.



I really hope that it was something as simple as the spark plugs, but if it was the plugs, a little upset that I didn't swap them earlier as I have been using my gas guzzler truck for commuting.
 
Just to throw this out there... have you tried cleaning or changing your IAC? Might be worth a check. Will definitely cause it to stall while idling and if it gets stuck open can cause vacuum issues and cause it to lose power. If you hold your foot on the gas pedal some so it doesn't have a chance to idle on its own will it still stall?
 
Just to throw this out there... have you tried cleaning or changing your IAC? Might be worth a check. Will definitely cause it to stall while idling and if it gets stuck open can cause vacuum issues and cause it to lose power. If you hold your foot on the gas pedal some so it doesn't have a chance to idle on its own will it still stall?

I haven't cleaned it in years, but maybe I will do it again just to be thorough.

I think it may have been do to resetting the ECU. I notice on multiple cars that after resetting the ECU, sometimes the first few starts are a little rough.

Either way, I might just clean it. IIRC, I think it was easy to get to and remove.

Thanks for the reply.
 
I think it may have been do to resetting the ECU. I notice on multiple cars that after resetting the ECU, sometimes the first few starts are a little rough.

Yea,... My car runs like crap after I disconnect the battery especially right after I start the car for the first time,.. It almost stalls then gets progressively better with each idle attempt.
It apparently takes about 100 miles to get a smooth idle back.
 
Back