Engine misfire?

dajiggalo

Member
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Mazda3s, strato blue
I had to call Mazda roadside assistance today to get my car towed to Byers Mazda (in Columbus). My car started jerking and the revs were jumping when I gave the car some gas (check engine light came on for a second). This kept going on for about half a mile regardless of what gear I was in so I parked in a local school parking lot. I was pretty pissed off at this point because the car just started fine and had no problems for about 1 mile and two traffic lights, when it went beserk on me. The dealer test drove it and said it was working fine but a engine diagnosis showed a misfire in one of the cylinders. Technician asked me what kind of fuel I was using, I said "87 regular from the same gas station as always." This is the second time this has happened (first time it was way more subtle, dealer "flashed" the engine for me). Anyone else had this problem?????



on a lighter note.... Somebody at the school called the cops on me. I guess being South Asian (tan complexion, black hair, and I haven't shaved in three days) sitting in an Elementary school parking lot must set off some sorta terrorist paranoia. Nothing to bad though, one local Worthington cop in a cruiser showed up and I started grinning (it doesn't take a genius to figure out why he was here...). Before he could start grilling on me on who-what-when-where-why, I whipped out my military ID (I'm a Corporal in the Marines by the way) and we chatted about the car instead. Turns out he drives an FC3S RX-7 and his wife drives a Ford Focus (no comment). Oh, and he likes my wheels (I told him my gunmetal wheels were actually silver, just covered with typical Mazda excessive brake dust)....
 
All I can say is fuel pump, A lot of Mazda 3's have defective fuel pumps including mine, your case is a lot more severe than others, before they put the pump on my car, the car did not get enough gas on startup and was consuming rediculous amounts of gas.
 
the pump would either work or not. unless your fuel pressure regulator failed too, no more fuel would be pumped than normal.
 
pdhaudio83 said:
the pump would either work or not... .
Not always. Imagine the pump rotor clearance being too high or slipping creating a low volume/pressure situation. There could be a manufacturing error creating a restriction in the inlet. It still flows, just not enough.
 
thats the point of the regulator- to regulate the psi. if it isnt getting enough, the pump will push harder...
 
pdhaudio83 said:
thats the point of the regulator- to regulate the psi. if it isnt getting enough, the pump will push harder...
No. It doesn't work like that. The pump has limits. Especially if it is malfunctioning. This is why people upgrade fuel pumps when they perform engine modifications. Fuel pumps have flow limitations. If it is malfunctioning, it's limitations are furthermore decreased. Possibly to the point that it can't support the vehicles requirements under certain operating conditions.
 
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The point here is that many Mazda 3 fuel pumps are deffective. Some people are having problems on startup like I did, it would never start the first time around. Others are having problems constantly or occasionaly. Just go to service and see what they say after they look at your car.
 
irr5302 said:
this car run with premium gasoline 91 or more octane

The car was designed for 87 octane. Unless you have poor quality fuel where you live, using a higher octane than required is at the very least a waste of money and at the worst, detrimental to operation.
 
I do not recomend anything over 89 octane for Mazdas, you really have to be a spirited driver 24/7 for 89 octane. The engine was tuned and calibrated to work at it's best and most efficiently at low octane fuels.
 
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