Misfire problem diagnosed!

this thread makes me wanna change the sock on my fuel pump housing... i get random misfire and cylinder 1 misfire... whats really weird is its only at start up... but i do believe this is my problem because when i put in a bottle of lucas fuel cleaner my car starts fine for a day
 
Does anyone have any good suggestions on how to clean the crap out of the gas tank?

I'm pretty sure I have some, after every fill-up I get some crazy hesitation and nearly stalling idle for a good 5-10 minutes until the stuff settles.

I'll gladly replace the filter sock, but I'd like to only have to do it once :)

Its probably just the sock filter. Most of the bits you'll find in the tank will be so heavy that they'll be sitting on the bottom.
If you really need to clean it out, get yourself a mity vac (harbor freight has a cheap knock off). It has a little catchment container that you can use to vac liquids/bits out of the tank.
 
Its probably just the sock filter. Most of the bits you'll find in the tank will be so heavy that they'll be sitting on the bottom.
If you really need to clean it out, get yourself a mity vac (harbor freight has a cheap knock off). It has a little catchment container that you can use to vac liquids/bits out of the tank.


Thank you for making this thread. I have someone coming over to check out my car now. If the data logger doesn't show a fuel injector issue then I am going to replace the filter/sock/screen.


http://www.autozone.com/R,2520898/v...partType,00220/shopping/partProductDetail.htm

http://www.napaonline.com/MasterPag...tNumber=FS0088&Description=Fuel+Pump+Strainer


If you can pre-plan you can order them here for much cheaper

http://www.rockauto.com/catalog/x,carcode,1387447,parttype,6212

Thanks again.
 
If you really need to clean it out, get yourself a mity vac (harbor freight has a cheap knock off). It has a little catchment container that you can use to vac liquids/bits out of the tank.

The Mity Vac models I saw are air, vacuum, or hand powered, but the literature did not list gasoline as one of the fluids for which it was intended. There may be an ignition hazard from static discharge, or the gasoline may damage the pump. Perhaps there is a specific model you are referring to which is rated for gasoline?
 
This is an easy job. Really! I pulled it, took it all apart like a ten year old with their first set of tools, cleaned it, and had it back in in 30 minutes. A couple friends were over so I stepped up the fun and put an unlit cigarette in my mouth while I was in the back seat. I hallered that I needed an ash tray and they flipped. LOL good times.

Open the garage when you do this. I had mine open but still had to turn the fan on.

Over 180K on a factory sock. First time it was cleaned. Wasn't as dirty as I would have thought. It did help my acceleration and hesitation issue.
 
The Mity Vac models I saw are air, vacuum, or hand powered, but the literature did not list gasoline as one of the fluids for which it was intended. There may be an ignition hazard from static discharge, or the gasoline may damage the pump. Perhaps there is a specific model you are referring to which is rated for gasoline?

The mity vac never touches the gas. It pulls a vac on a little container which in turn creates suction on a tube that you stick in the tank. Fluid comes up the tube and lands in the container -- never making its way to the actual mityvac pump.
 
Alright, here is my problem. P0301 Misfire cylinder one. Replaced ignition coil, cleaned and regapped plugs, pulled and cleaned the fuel filter, seafoamed intake system, new air filter, cleaned MAF, and ran 3/4 can of seafoam in my gas. Plug wires are about a year old.

First half a tank is golden. No issues at all. After that is bogs at higher revs, say 3500. Feathering the gas helps but after a while it doesn't work either. Gunning it causes total loss of acceleration.

Filled up and added a can of Gumout just in case the Seafoam didn't clean the injectors completely.

Had a friend that owns a shop take a look and he says that a full tank is nearly impossible to warm up enough to vapor lock the pump. At half a tank it is quicker to do so.

So, new pump?

If so, http://catalog.mercedesshop.com/ShopByVehicle.epc?q=2002-Mazda-Protege--5-Fuel--Delivery&yearid=2002%40%402002&makeid=MA%40%40Mazda&modelid=PRO%2D5%2D002%40%40Protege+5&catid=E%40%40Fuel+Delivery&subcatid=E3000@@Fuel+Pump&mode=PA is the cheapest I have found anywhere. $98.40 for a pump or rebuild kit? Holy moly!


Any other options?
 
mic check....is this thing on?


Here is what I have so far:
before condemning the fuel pump, look at your injectors. swap inj. #1 and #2. clear codes. go for drive, wait for misfiring to start and cel to appear. check codes. if new code is p0302 then your injector is bad because the misfire moved to cyl. 2 along with the injector.

Thoughts?
 
DEFINITELY a good idea to try the injector swap! You can only swap 1 with 2 and 3 with 4 (keep the colors together).
 
I just want to add I did this to our P5 this evening. Not sure if anyone else has done what I did, but I took my air nozzle and blew it lightly in burst into the feed line out and return on the pump. Not sure which one it was but one of them spewed out a thick nasty crap of dark brown and black. I did it until nothing came out. I almost want to suggest this to others, however do it with cautions, you don't want to blow out a seal or anything. Works like a champ. I picked my strainer up from advanced auto for $9 which was in stock.

As for the work itself, the bolts were all rusted to horrific proportions. I used a few tools to remove them. First was my impact driver. Worked bery well for most. A few were too far gone. I then used the pointed pic. I hammered straight on the side to give it a dimple, then cocked it sideways a tad and tapped until loose. All came out with minimal effort. The tops were rusty, however once they broke loose they came out with my fingers. I also sprayed the car with a pentrant and let it sit for about 15 minutes to absorb. I tried using bolt extractors but had no luck, they just ate the heads round and smooth. Those are the ones I had to use the pick for. If I would have went straight for the impact driver I honestly think I could have gotten them all out. Also side note for those who have never used one....1, they are pretty cheap at sears 2, you have to give it good blows for it to work well.
-Keith
 
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Look up the vtcs removal how-to. Removing the fuel rail/injectors should be part of that how-to.
 
ok... now wheres the how-to on swapping injectors pls :)


Here is the initial page on it. Shoot me a pm with your email addy and I will send you the pdf.


I attempted to pull my iac last night, the phillips were extremely tight and I didn't want to strip them so I left it alone and pulled my intake and cleaned my TB. Pulled the plugs afterwards and cleaned the soot off.

Will have to see.
 

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I just want to add I did this to our P5 this evening. Not sure if anyone else has done what I did, but I took my air nozzle and blew it lightly in burst into the feed line out and return on the pump. Not sure which one it was but one of them spewed out a thick nasty crap of dark brown and black. I did it until nothing came out. I almost want to suggest this to others, however do it with cautions, you don't want to blow out a seal or anything. Works like a champ. I picked my strainer up from advanced auto for $9 which was in stock.

As for the work itself, the bolts were all rusted to horrific proportions. I used a few tools to remove them. First was my impact driver. Worked bery well for most. A few were too far gone. I then used the pointed pic. I hammered straight on the side to give it a dimple, then cocked it sideways a tad and tapped until loose. All came out with minimal effort. The tops were rusty, however once they broke loose they came out with my fingers. I also sprayed the car with a pentrant and let it sit for about 15 minutes to absorb. I tried using bolt extractors but had no luck, they just ate the heads round and smooth. Those are the ones I had to use the pick for. If I would have went straight for the impact driver I honestly think I could have gotten them all out. Also side note for those who have never used one....1, they are pretty cheap at sears 2, you have to give it good blows for it to work well.
-Keith


Did it run better afterwards?

The 8 screws that hold the pump in are 4mm. I stripped 4 out of 8, so I went to the hardware store and switched them all out to bolts.

I think it takes longer to get the fuel lines unhooked then anything.
 
I just want to add I did this to our P5 this evening. Not sure if anyone else has done what I did, but I took my air nozzle and blew it lightly in burst into the feed line out and return on the pump. Not sure which one it was but one of them spewed out a thick nasty crap of dark brown and black. I did it until nothing came out. I almost want to suggest this to others, however do it with cautions, you don't want to blow out a seal or anything. Works like a champ. I picked my strainer up from advanced auto for $9 which was in stock.

As for the work itself, the bolts were all rusted to horrific proportions. I used a few tools to remove them. First was my impact driver. Worked bery well for most. A few were too far gone. I then used the pointed pic. I hammered straight on the side to give it a dimple, then cocked it sideways a tad and tapped until loose. All came out with minimal effort. The tops were rusty, however once they broke loose they came out with my fingers. I also sprayed the car with a pentrant and let it sit for about 15 minutes to absorb. I tried using bolt extractors but had no luck, they just ate the heads round and smooth. Those are the ones I had to use the pick for. If I would have went straight for the impact driver I honestly think I could have gotten them all out. Also side note for those who have never used one....1, they are pretty cheap at sears 2, you have to give it good blows for it to work well.
-Keith

Just to clarify, are you saying that one of your fuel lines was clogged?!?!? IMO, you should get your injectors serviced if you had junk in the lines after the (cough) filter/tank screen.

I'm wondering if this is my problem now! I just dropped it off at the stealership an hour ago -- 1st time its ever been to any mechanic outside a alignment.
 
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