Stalling Issues, battery issue, headlight issue

Hey Guys! I have an automatic 2003 Mazda Protege5 that I bought brand new. She's my baby and I want to keep her as long as I can. About a week or so after I bought it, it stalled when I stopped to pay a toll. It started right back up, but I took it in to the dealership because it didn't seem right. They couldn't reproduce the issue. Long story short, 17 years later, I'm still having the same issue. Thankfully, it only stalls when I go to step on the accelerator after being at a stop light or stop sign. Back in 2016, I think, I had issues with it misfiring while driving, almost stalling on me. Took it to Mazda, I had a bad coil pack, they replaced it. I replaced the PCV valve in 2017 and that helped some, but still have issues. In 2018, it started throwing codes about the pre cat (don't remember exactly what they were). I had the pre cat replaced and the 02 sensors. She is still having issues and stalls every now and then. It just did it about a week ago. I'm not sure if I need to replace the other coil pack, the IAC, or the EGR, or something else???? Any advice would be great! This is my biggest issue because I'm afraid if I don't figure out what is causing it soon, she's not going to last too much longer. :(
Also, I have some battery issues. Car wouldn't start, replaced battery. A week later, came out to a dead battery again. I was told it was the starter cable connection. It was corroded. They cleaned it off, but did not replace it. This is my 4th battery, I think, since I bought the car in 2003.
And does anyone else have issues with their headlight bulbs going out often. I seem to replace mine about twice a year, since 2004.
I absolutely love my car and can't picture myself driving anything else right now. I have a little car knowledge, but I haven't done any work on it myself except replacing bulbs, air filter, pcv valve, so I would have to take it to a mechanic for any fixes.
Any advice would be greatly appreciated!! Thanks! ZOOM! ZOOM!
 

pcb

The Diagram Dude
:
2002 MP5
How is your idle?
Is it at 800 RPM without bouncing around?

Does your car burn oil? If so your EGR could be fouled and need cleaning or replacement if you can't clean it yourself.

The IAC could be fouled as well.

I don't think a coil pack would fail without throwing a code and only be a problem when you touch the gas.

The fact that your car has been doing this since day one, is a bit strange.
I would suspect something is a little off like the idle RPMs or throttle position sensor?

If it's not a safety issue for you, then you may be able to live with it.




You're not doing too bad for batteries, 2-5 years is kinda the norm.

Keep in mind that our alternator only puts out 77 Amps, so if you've got your lights on, your blower running, your wipers going, your rear defrost on, and your stereo cranked, (especially a high power aftermarket unit), you're going to be pulling huge amps out of your battery because the alternator can't keep up.

That's really hard on the battery.
They wear out from being discharged, even if they get charged back up by turning off some electrical loads.

Your new battery being dead in a week is a sign of something wrong.
If it went dead just sitting there, then you have a power drain somewhere.
The car isn't supposed to draw more than 20 mA with the key removed.

You could have drained the battery through the corrosion to ground?



The headlight issue is quite common. Our car eats headlight bulbs. Some dielectric grease on the connector can help.

Some guys just buy a dozen cheap bulbs at a time and keep them in the car for their monthly replacement. Lol

Don't buy the expensive bulbs, they cost too much to replace all the time.
 
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pcb

The Diagram Dude
:
2002 MP5
Your engine idle speed may be a little off.

And it is supposed to increase by 50-100 RPMs when the power steering switch or the AC is turned on.












Your tachometer in your car isn't considered accurate but it's pretty close.

See if your idle goes up when you crank the steering wheel or turn on the AC.
 
How is your idle?
Is it at 800 RPM without bouncing around?

Does your car burn oil? If so your EGR could be fouled and need cleaning or replacement if you can't clean it yourself.

The IAC could be fouled as well.

I don't think a coil pack would fail without throwing a code and only be a problem when you touch the gas.

The fact that your car has been doing this since day one, is a bit strange.
I would suspect something is a little off like the idle RPMs or throttle position sensor?

If it's not a safety issue for you, then you may be able to live with it.




You're not doing too bad for batteries, 2-5 years is kinda the norm.

Keep in mind that our alternator only puts out 77 Amps, so if you've got your lights on, your blower running, your wipers going, your rear defrost on, and your stereo cranked, (especially a high power aftermarket unit), you're going to be pulling huge amps out of your battery because the alternator can't keep up.

That's really hard on the battery.
They wear out from being discarded, even if they get charged back up by turning off some electrical loads.

Your new battery being dead in a week is a sign of something wrong.
If it went dead just sitting there, then you have a power drain somewhere.
The car isn't supposed to draw more than 20 mA with the key removed.

You could have drained the battery through the corrosion to ground?



The headlight issue is quite common. Our car eats headlight bulbs. Some dielectric grease on the connector can help.

Some guys just buy a dozen cheap bulbs at a time and keep them in the car for their monthly replacement. Lol

Don't buy the expensive bulbs, they cost too much to replace all the time.

Thanks!
o on cold start, it idles about 1500-2000. At stop lights and such, it's around 700-800, and bounces occasionally. It can get down to almost 500 sometimes at stop lights and when it does, it sounds like its going to stall. Sometimes it does, sometimes it doesn't.
Car does not burn oil. I do a lot of short distance, stop and go driving. I live 2.6 miles from work with 8 stoplights at 35mph ~12min drive. I've been doing that since about 2008, give or take a few miles here and there. A few days a month, I take 20min drives on the highway. I changed my oil every 3000 miles until about 2011(about 3-4 times a year), when my driving distance declined more and switched to every 5000(2-3) times a year. Now I change it twice a year, March and September. Haha. But I check it regularly, because if I end up driving more than usual, I will start to run low by month 5. Like I said, she's my baby.
I was thinking IAC valve and bought one from Rock Auto, but nobody will replace it for me and I have no idea what I'm doing and can't find a video of it.
The reason I was thinking coil pack was because my check engine light didn't come on when the one went a few years ago. I don't know if it threw any codes though.
As for the battery, I was told the starter wire connector was corroded. The place I took it too just cleaned the connection off but didn't replace it. I do have an aftermarket strep. I take the faceplate off when I get out of the car.
I'm so relieved I'm not the only person with the headlight issue. Everytime I go into a store to buy bulbs someone always asks me if I need help, because a female in an auto parts store must need help, and I say "No, I change my headlights almost as much as I change my underwear so I know what I'm looking for." Lol.
Thanks so much for advice! I'm definitely going to replace the IAC especially since it's already sitting in my car. Haha. Just need to find a video of it and get the right tools and should be able to do it myself, hopefully. You wouldn't happen to know of any diy videos for replacing the IAC? Thanks again!
 
Your engine idle speed may be a little off.

And it is supposed to increase by 50-100 RPMs when the power steering switch or the AC is turned on.












Your tachometer in your car isn't considered accurate but it's pretty close.

See if your idle goes up when you crank the steering wheel or turn on the AC.

Thanks. I will try that tomorrow. I never took notice. Haha. I know if I crank my steering too far, it makes a not so good noise. Haha.🤷🏼‍♀️
 

pcb

The Diagram Dude
:
2002 MP5
Thanks. I will try that tomorrow. I never took notice. Haha. I know if I crank my steering too far, it makes a not so good noise. Haha.🤷🏼‍♀️

Yeah, it's not a good thing. Lol
You've got five seconds before your fluid overheats.



Probably just turning the steering wheel while the car is parked will increase the pressure and kick in the pressure switch. I'm guessing that your RPMs are too low and when you hit the throttle, it just bogs down and stalls? Keep a close eye on your Tachometer and if it ever reads around 500 RPMs or less, then it's too low.
 

pcb

The Diagram Dude
:
2002 MP5
Keep in mind too that the IAC needs to relearn how to idle the car after the battery is disconnected.

My car nearly stalls at idle while it's relearning.

I don't know how your stalling coincides with your dead battery replacements and other servicing though? (you're supposed to disconnect the battery for almost all servicing.)
 
I can understand the IAC needing to relearn, but I don't think that explains it doing it from the beginning. The first time it happens, it was a warm day, July, had only been running less than 5 min, and top speed maybe 35mph. Stopped to put change in till and when I went to hit the gas, it stalled.
 

pcb

The Diagram Dude
:
2002 MP5
Perhaps if the battery was disconnected before you took ownership?
How many miles were on it the first time it happened?
 

pcb

The Diagram Dude
:
2002 MP5
A related thread...
 
Perhaps if the battery was disconnected before you took ownership?
How many miles were on it the first time it happened?

There was 8 miles on the car when I bought it. It still had the plastic on it. Lol.
The first time it stalled, there was probably less than 200 miles on it.
I turned my AC on this morning while sitting at a stop light and rpm went from 700 to about 800. And I was watching the tach whenever I came to stop and the needle kinda bobs up and down slightly in the 700 range.
So if it goes down to 500 would that be IAC needing to be replaced?
 

pcb

The Diagram Dude
:
2002 MP5
Your battery may have been removed and charged just before you picked up the car when it was new.
If the car was sitting at the dealership for a while, it's good practice to charge up the battery.

If your idle drops really low, it could be the IAC relearning if the battery was recently dead or disconnected or if it happens all the time, the IAC could be "sticky" and it needs to be cleaned or replaced.
 

pcb

The Diagram Dude
:
2002 MP5
...
Thanks so much for advice! I'm definitely going to replace the IAC especially since it's already sitting in my car. Haha. Just need to find a video of it and get the right tools and should be able to do it myself, hopefully. You wouldn't happen to know of any diy videos for replacing the IAC? Thanks again!

No, I don't know of any videos.
What I remember is that it's located toward the top and back of the engine near the firewall.
It's really tight in there with very little room to work.
You'll need a small 1/4" stubby ratchet handle and a socket to fit in there.
 

pcb

The Diagram Dude
:
2002 MP5
New bulb socket adapters can help with your headlight issues.
They get all burnt up and crispy, then don't conduct electricity as well, then they get even hotter.

 

pcb

The Diagram Dude
:
2002 MP5
FWIW, when my idle starts to stumble, I put half a can of Seafoam in the brake booster vacuum line and half a can in the gas tank.

I put a shot of Seafoam in with gas at every fill-up. My idle is fine now, and I haven't had to put any in the brake booster for years.

 
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Strangely, I haven't looked at mine but I'm assuming the P5 has a cat converter on it... Being clogged will cause hesitation when stepping on the gas which could cause the stalling if bad enough...
 
:
Dallas, TX
:
2003 Protege5
Dielectric grease is a must for our P5 headlights - on both sides of the adapter PCB displayed above. Made my bulbs last much longer. I've had my '03 P5 for 18 years now. Battery goes out every four years in the heat if summer, just like clockwork.

Use Hitachi coils only - and definitely not AutoZone coils. Hitachi are the OEM brand and they'll last forever and not leave you running on three cylinders in an REI parking lot. Not that I'm bitter.
 
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