Engine shut off, PLEASE HELP

[WRX504]

I had been throwing a misfire code and had been told by the dealership it may be nothing. My car has 100k on it so I decided I should replace the spark plugs and IACV gasket. On my way to do this my car shut off. I was in 4th gear and lost complete power, it will start but only for a split second before shutting back down. The IACV valve looks clean and my fuses are ok. I can also hear my fuel pump buzzing when the car is in the ON position so I figured that was fine.. Still have not replaced the spark plugs but figured that wouldnt fix it. I have no idea what is going on. Any ideas?

[wrxtreme06]

what code were you getting?

[WRX504]

It was P0304 I think. A misfire on cylinder 4. I dont have a scanner to read any new possibly codes.

[Spencer3636]

Did you do anything with the MAF sensor? If your MAF is disconnected, installed wrong, extremely dirty, or somehow broken you will get similar symptoms.

[WRX504]

Did you do anything with the MAF sensor? If your MAF is disconnected, installed wrong, extremely dirty, or somehow broken you will get similar symptoms.

I had disconnected it a week ago. What can I use to clean it?

[Spencer3636]

I had disconnected it a week ago. What can I use to clean it?

They sell MAF cleaner at most auto part stores. I believe it is the same thing as Air intake cleaner it just doesn't have as much pressure in it so you don't damage your MAF. (don't quote me on this!! LOL)

I would take it back out and give it a look over, make sure that little "bulb looking thing" is still hanging in there. Give it a cleaning and when reinstalling make sure you put it in the right way and that it is seated completely. Also make sure the connectors are clean and locked into place.

I'm just going out on a limb here since the symptoms are similar, not sure that it would just go out in 4th gear, but hey, anything can happen right?

Do you have an aftermarket intake?

[WRX504]

They sell MAF cleaner at most auto part stores. I believe it is the same thing as Air intake cleaner it just doesn't have as much pressure in it so you don't damage your MAF. (don't quote me on this!! LOL)

I would take it back out and give it a look over, make sure that little "bulb looking thing" is still hanging in there. Give it a cleaning and when reinstalling make sure you put it in the right way and that it is seated completely. Also make sure the connectors are clean and locked into place.

I'm just going out on a limb here since the symptoms are similar, not sure that it would just go out in 4th gear, but hey, anything can happen right?

Do you have an aftermarket intake?

No intake, just the stock box with the end piece removed after the air filter. its weird cause it starts right up then just shuts down every time. I will try cleaning the MAF sensor.

[Spencer3636]

No intake, just the stock box with the end piece removed after the air filter. its weird cause it starts right up then just shuts down every time. I will try cleaning the MAF sensor.

Why did you take that off? It stays started for just a second then bogs out right?

[WRX504]

Why did you take that off? It stays started for just a second then bogs out right?

that's how the car was when I bought it. Ya it starts for literally a half second and then bogs out. This happens every time you try and start it.

[Spencer3636]

that's how the car was when I bought it. Ya it starts for literally a half second and then bogs out. This happens every time you try and start it.

Without seeing it and just from assuming the car was running fine without any issues but the misfire I'm thinking you are MAF related.

Anyone else have any input?

With a bad plug or coilpack the car should start it would just run like crap.

[WRX504]

Without seeing it and just from assuming the car was running fine without any issues but the misfire I'm thinking you are MAF related.

Anyone else have any input?

With a bad plug or coilpack the car should start it would just run like crap.

I appreciate the help. I have also read it could be a O2 sensor or ground wire connection. My battery cables are in bad shape do you think this could be part of the problem?

[Spencer3636]

Well let's see, you have a front O2 sensor located right below your UP Pipe, (you should get that stock Up out or there ) a rear O2 sensor at the end of your Down pipe. What kind of exhaust do you have? Catless?

And you also have a temperature probe near the top of your Up Pipe. With a little bit of wiggling there all pretty easy to get too. If you have ever pulled an O2 sensor you will know they don't like to come out without a fight sometimes. I would suggest an O2 removal socket.

Clean those battery terminals! Are the wires themselves damaged or just the connectors? for a few bucks you can get new terminals and some cleaner, or just use baking soda and a tooth brush.

[WRX504]

Well let's see, you have a front O2 sensor located right below your UP Pipe, (you should get that stock Up out or there ) a rear O2 sensor at the end of your Down pipe. What kind of exhaust do you have? Catless?

And you also have a temperature probe near the top of your Up Pipe. With a little bit of wiggling there all pretty easy to get too. If you have ever pulled an O2 sensor you will know they don't like to come out without a fight sometimes. I would suggest an O2 removal socket.

Clean those battery terminals! Are the wires themselves damaged or just the connectors? for a few bucks you can get new terminals and some cleaner, or just use baking soda and a tooth brush.

I have a 3 inch cat less down pipe and cat less up pipe. Crappy mid piping and out of a STI axle back. Bought the car like this. It is just the ends of my battery cables are pretty corroded. Do you know if it is hard to replace the end of the cables? Anyway I will try cleaning or just replacing them. How can you tell if the O2 sensor is bad?

[Spencer3636]

I have a 3 inch cat less down pipe and cat less up pipe. Crappy mid piping and out of a STI axle back. Bought the car like this. It is just the ends of my battery cables are pretty corroded. Do you know if it is hard to replace the end of the cables? Anyway I will try cleaning or just replacing them. How can you tell if the O2 sensor is bad?

Good times good times I don't even know the brand of my midpipe and axleback, they just sound good that's all it's for anyways.

Super easy to change them out, wire cutters and some cleaner

If one of your o2's are bad your car should throw a CEL code. Which you obviously cant see since the car wont start LOL.

If you pull them out and the tips are white, or caked with junk that is a good indication that something is wrong.

[WRX504]

Good times good times I don't even know the brand of my midpipe and axleback, they just sound good that's all it's for anyways.

Super easy to change them out, wire cutters and some cleaner

If one of your o2's are bad your car should throw a CEL code. Which you obviously cant see since the car wont start LOL.

If you pull them out and the tips are white, or caked with junk that is a good indication that something is wrong.

Thanks. Now I just have to wait to the weekend so I can try these things. Car is in the mountains at a friends about 40 miles away. Riding the mountain bike to work this week.