2003 Protege5 Bogging

Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
First off I wanna say what's up y'all!?! I just recently bought my first ever Mazda last week and it ran great the first day I had it. Then on the 2nd day it ran great for the first 1/4 mile down my road to the stop sign and taking off from the stop it fell flat on it's face. So I tried pedaling it to get power back with no avail so I had to stomp on it because a car was coming up on me and once I hit 12 mph it lunged forward and instantly regained power. So I took it home and started researching when I found this wonderful site and here I am now.

Since then I've went on plenty of test rides to get a better feel for exactly how it was acting. There is no set path that this bogging follows, it does it on the highway at high speeds, it does it starting from a stop and it even rarely bogs down when it is idling. So I replaced the air intake snorkel because it was cracked pretty good and it ran great for about 15 minutes then bam I went to take off and she fell flat on her face. So my dad suggested the maf sensor and I replaced it instead of just cleaning it and it ran great for about 15 minutes again then same crap. Then I disconnected the maf sensor plug and started it and let it run for 30 seconds, shut it off and reconnected the maf sensor plug. I fired it up and it ran great for about a day then quickly the issue came back! I tried a few things like checking wire connections, resetting the ecm and checking grounds and during the middle of my test drives I needed gas so I filled it up. Once I filled the tank up completely it stopped having any issues whatsoever. I continued test driving it and it didn't bog or act up once until the gas gauge dropped down to 5/8ths of a tank. It started occuring slowly and as the fuel level dropped lower the symptoms continued to increase and get worse...

This leaves me to believe it's a fuel issue and I had read a thread when I first found this site that mentioned something about a fuel pulse sensor or something to that effect, not the fuel pressure regulator, fuel filter or fuel pump but something different. I've searched for the last 2 hours and can't find that thread again so if anyone could fill me in on what it's actual name is I'd greatly appreciate it!

Now on to my question, do y'all think I'm correct about it probably being an issue with the fuel system since the issues completely go away when the gas tank is full and if so where should I start exactly with testing? I have the 327 Bluetooth reader coming in the mail tomorrow, so until then I can't check the codes. Since I've had it the thing hasn't thrown a single code until tonight once it reached a quarter tank of gas and it basically fell flat on it's face 90% of the time I hit the throttle.

To my knowledge it has no modifications, it's 100% stock and it's a nonturbo 2.0l with an automatic transmission at 142,600 miles. I bought it from an elderly couple that used it for church and a grocery getter. They always had it serviced regularly and took great care of it.

I greatly appreciate any input, thanks erryone!
 

pcb

The Diagram Dude
:
2002 MP5
This is the fuel pulsation damper...





I think you may have a clogged high-pressure fuel filter and/or a bad fuel pump.
(the low-pressure filter is the strainer, you should get a new one as well. They're just a few bucks.)

It could make sense that if you had a full tank of gas, it would add just enough pressure to the intake of the fuel pump (from the depth of the gas) that it works at first until the fuel level drops.

I think it might be smart to replace it.
It's not that much money and is relatively easy to do unless your car is a rusty turd like mine.





You could do a fuel pressure test to help verify the pressure and fuel rate.




Here's a link to the service manual...




Here's a link to a how-to I wrote about replacing the fuel filter.

 
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Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
Great info, I appreciate it and the diagrams!!! Unfortunately I gotta work tomorrow so I won't be able to get cracking on it until evening time.

Do I have to drop the tank to change the pump or is there an access panel in the cab?

I actually got really lucky, it's been garaged since it was brought home from the dealership and it's never been driven in snow... At least that's what the single previous owner told me, this car is super clean inside and out
 

pcb

The Diagram Dude
:
2002 MP5
Yes, there's an access panel under the rear seat.

The screws aren't Philips, they are JIS.
A Phillips will strip the screw heads.

If your CEL is flashing it is an engine misfire.
It's the only code that flashes the CEL.
Misfiring can wreck your precat in seconds.

If your fuel filter is clogged, it can overstress and burn out your fuel pump.

The fuel pump fits inside the high-pressure fuel filter and you swap it into the new filter.


 
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:
2003 protege 5
Bad coils usually throw codes and cel will flash. It sounds like a fuel issue from what youve described. Id go with a new pump and filter if not for anything but piece of mind. Another thing to check is the fuel pump relay under the hood. They get crispy and corroded after while.
Id also put the original maf back after you clean it real good. Aftermarket sometimes dont work as well.
Also whenever you disconnect the battery the car has to learn how to drive again and it could take up to 100 miles to run correctly. Might stumble and stall when stopping.
 

Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
If your fuel filter is clogged, it can overstress and burn out your fuel pump.

The fuel pump fits inside the high-pressure fuel filter and you swap it into the new filter.
So I have to order the "strainer" (filter) and the fuel pump as 2 separate items? As in they don't come as a set sold together?
 

Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
Bad coils usually throw codes and cel will flash. It sounds like a fuel issue from what youve described. Id go with a new pump and filter if not for anything but piece of mind. Another thing to check is the fuel pump relay under the hood. They get crispy and corroded after while.
Id also put the original maf back after you clean it real good. Aftermarket sometimes dont work as well.
Also whenever you disconnect the battery the car has to learn how to drive again and it could take up to 100 miles to run correctly. Might stumble and stall when stopping.
I checked all fuses and relays for visual deficiencies and they all "looked" good, I'm getting my meter back from my dad tomorrow so I can test anything needed.

Yeah, I had already thought about that with the maf since I'm pretty certain it wasn't a problem.

When the check engine light came on it flashed the entire time it was running and now it stays lit up solid every time I drive it. I've put 75 miles on it this evening stopping periodically to top the tank off and still no symptoms as long as the fuel level stays up near full.

i really do appreciate y'all's time and input!
 

Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
I've got 3/4s of a tank of gas left and I'm up to roughly 115 miles of test driving, so on my way to work in the morning it should tell me if it was just learning to drive after the maf replacement. If it starts bogging I'll stop and fill up the tank... At that point, fixing the issue again with a full tank of gas should definitely point to a fuel system failure! IMO at least... Fingers crossed lol
 
:
2003 protege 5
A blinking cel makes me think coil packs. Id wait for your code reader before you spend any money. But generally when i get a used car ill replace the plugs thermostat water pump and fuel filter. If theres no maint history i try to do the fuel pump and timing belt also. I had an issue once where i replaced the plugs and not 300 miles later a coil pack failed. Those items should give you a reliable car for many miles and not leave you stranded. Hopefully the older couple gave you some paperwork with maint history and you can cross some of those items off. Either way, plugs and coil packs and even a fuel pump shouldnt be too bad unless youre in snow country.
I got Hitachi coils from oriellys as import direct brand. And a denso pump from rock auto with a strainer. Hope that helps
 
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Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
A blinking cel makes me think coil packs. Id wait for your code reader before you spend any money. But generally when i get a used car ill replace the plugs thermostat water pump and fuel filter. If theres no maint history i try to do the fuel pump and timing belt also. I had an issue once where i replaced the plugs and not 300 miles later a coil pack failed. Those items should give you a reliable car for many miles and not leave you stranded. Hopefully the older couple gave you some paperwork with maint history and you can cross some of those items off. Either way, plugs and coil packs and even a fuel pump shouldnt be too bad unless youre in snow country.
I got Hitachi coils from oriellys as import direct brand. And a denso pump from rock auto with a strainer. Hope that helps
He said unfortunately when his wife passed away his kids accidentally threw out all of his vehicle maintenance papers. He said he kept everything from every car he had owned so when his kids came across shop receipts from the 60s n 70s they just threw out the entire box not realizing even his current vehicle paperwork was in there. Just my luck!

But like was suggested earlier, I'ma replace some parts just to ease my mind. I'll prolly just go ahead and replace the filter/pump, coils plugs n wires, crankshaft sensor (it has some light fraying in a couple spots on the wiring along with the actual sensor looks like the oldest n dirtiest part under the hood), thermostat and the o2 sensors. Now, do y'all think I should just go ahead and replace the pulsation damper? I plan on testing each individual part to isolate the actual problem, but as wise as piece of mind replacements anything else y'all suggest I could replace or anything I listed that I should actually just leave be if it's not part of the problem?
 

pcb

The Diagram Dude
:
2002 MP5
So I have to order the "strainer" (filter) and the fuel pump as 2 separate items? As in they don't come as a set sold together?
You can buy the entire "fuel sender unit" from the dealership but it's over $500.

Even then dealership can say that the unit isn't serviceable and doesn't sell the parts separately.

You should also get a new gasket.
It comes with new screws as well.


 

pcb

The Diagram Dude
:
2002 MP5
When the check engine light came on it flashed the entire time it was running and now it stays lit up solid every time I drive it.
When you get a misfire, the CEL flashes and the car goes into limp mode, where it does everything it can to stop the misfiring.
It reduces the timing advance and floods the engine with fuel.
When the misfiring stops, the CEL goes solid and you are stuck in limp mode, then the car slowly tries to go back to normal.
 

pcb

The Diagram Dude
:
2002 MP5
A blinking cel makes me think coil packs.

If the fuel pressure is too low the engine will misfire, but quality, new coils are never a bad idea or a waste of money.
I didn't wait for problems and just replaced my coils.
 

pcb

The Diagram Dude
:
2002 MP5
Now, do y'all think I should just go ahead and replace the pulsation damper?
I don't think that it's necessary.
I don't remember anyone replacing it and it isn't listed at RockAuto.

As far as I know, it is just a simple device kinda like a half-filled balloon that absorbs pulsation/vibration in the fuel delivery system.

If it's not leaking gas, it's probably fine.
 

pcb

The Diagram Dude
:
2002 MP5
Keep in mind, that you are now stuck in limp mode as well as your original problem, plus your car is relearning how to idle the car if you disconnected the battery.

I hope you make it to work. Lol
 

pcb

The Diagram Dude
:
2002 MP5
... Another thing to check is the fuel pump relay under the hood. They get crispy and corroded after while.
I remember a guy whose car would die spontaneously out of nowhere and had it looked at and everything tested fine but it still kept happening.
He was on the verge of getting rid of the car.
It was a safety issue.

Finally, the mechanics fully warmed up the car and found that the fuel pump relay would only fail when the car was hot.

They replace the fuel pump relay and his car was fixed.
 

pcb

The Diagram Dude
:
2002 MP5
... I'll prolly just go ahead and replace the filter/pump, coils plugs n wires, crankshaft sensor (it has some light fraying in a couple spots on the wiring along with the actual sensor looks like the oldest n dirtiest part under the hood), thermostat and the o2 sensors.
Apparently, the best plugs to use for our car are the regular NGK V-Groove copper plugs.

They give the strongest most reliable spark, but they do wear quicker and need to be re-gapped or replaced more often, but that is an easy job with our car.

The regular plugs are dirt cheap too.
 

pcb

The Diagram Dude
:
2002 MP5
You may want to consider an engine flush and fuel system treatment as well.

Our engine is prone to piston oil ring seizure and starts to burn oil.

It seems like at least half the people here on the forum are burning oil.

I use seafoam, which some say is just snake oil, but my car doesn't burn a drop of oil.

You can put half a can in the oil to flush the engine and half a can in the gas tank to clean the fuel system.

After I flushed the crap out of my engine, I put half a can in the oil at every oil change and leave it in until the next oil change, and I put a shot in the gas at every fuel fill-up.

My idle is as smooth as glass now and hasn't bounced around since I started using it.

At the very least, make sure you change your engine oil every 3,000 miles to flush out all the burnt up brown crap.
 

Halfbaked

The F*** Up King
:
Depths of Hell
:
'03 Protege5
At the very least, make sure you change your engine oil every 3,000 miles to flush out all the burnt up brown crap.
I'm a stickler for 3k oil changes, I don't ever miss that marker for my oil changes!

Thanks for the info, I'll read/reply when I can since I'm at work. I appreciate it!
 
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