Starts, idles for 2 seconds, then dies / Bad o2 Sensor?

[iguanahotsauce]

I have been reading through pages and pages of different threads trying to figure out my problems. I am currently getting about 15.5mpg and I only boost a few times a tank. At first I figured it was because I was working on the car a lot and letting it idle a lot. But now I'm on my third tank of gas and I have 125 miles at half way in between 1/4 and 1/2. When my car hit's E it takes exactly 13 gallons to fill it up. I added a can of seafoam into my last tank to see if that would help because the car had been sitting for six years when I got it and it had bad fuel in it. So What I am thinking is that my o2 sensor is bad and causing me to run very rich. I tested it with a voltmeter and it's bouncing around but it's not going constantly from .1 to .7 it's going from 0 to .4 or .5 and then back down to 0 and then up to .675 and then it repeats. What I am trying to figure out is if it is actually bad or if I am having some other problem that's causing me to get bad gas mileage.

 

[Calan]

O2 voltages are inconsistent at best. The main thing is that it's cycling, which it sounds like it is (although that does seem to be low).

What are you using for a data logger? You need to fill out your profile so we can see what mods you have on your car. Take a look at my profile if you'd like for an example of the info we'd like to see.

Nice choice of DSM BTW

 

[XiKeiyaZI]

If it's been sitting for that long, then a few immediate things that come to mind are.

1 : 02 Sensor
2 : Fuel Filter
3 : Dirty Fuel Tank corrupting fuel
4 : Bad Intake Filter
5 : Failing MAF/Bad connection
6 : Spark Plugs
7 : Plug Wires

Make sure to check out everything. An 02 sensor is a cheap thing to resolve an issue, just be sure that's your issue. I'd pull it and check out it's condition, make sure it's not corroded or covered in goop.

 

[iguanahotsauce]

I don't have a logger yet. I am looking at getting a pal m100 but I am really strapped for cash right now. This is my daily driver for driving to the college and I have spent a few hundred dollars getting everything fixed and it is almost done, hopefully . My car is completely stock. I am trying to get it running perfectly before I start to mod it. I have changed the fuel pump, fuel filter, air filter, thermostat, Coolant Temp Sensor, plugs and plug wires (My plug wires caught on fire about a week ago, the same day I was going to change them). The car had been sitting for about 6 years when a family friend gave it to me. The timing belt broke on him about 1000 miles before he quit driving it so he had a lot of engine work done on it about 1500 miles ago. I didn't take the fuel tank out and clean it but I drained the tank and ran some seafoam in it.

I know it's not terribly expensive to get a new o2 sensor but right now after dropping $1200 on next quarters tuition $50 is kind of a lot because I don't have much cash left

How would I go about testing the MAF to see if it is bad?

I was going to go pick up the parts to make a boost leak tester to see if I have any major leaks but I don't think I do. I am at about 19 in hg at idle and I can hit about 10psi when I boost.

 

[XiKeiyaZI]

I was going to go pick up the parts to make a boost leak tester to see if I have any major leaks but I don't think I do. I am at about 19 in hg at idle and I can hit about 10psi when I boost.

The search function for the MAF will work wonders for you.

For the leaks, it is VERY possible that you have a vacuum/boost leak. Even if you're pulling a decent vacuum and hitting 10PSI, it doesn't mean that there's not a leak that's robbing you of power and mileage. Until you perform a boost leak test and soak EVERYTHING with soapy water, you'll never know.

 

[Calan]

My plug wires caught on fire about a week ago, the same day I was going to change them.

Ehhh... care to explain that one in a bit more detail? I haven't heard of plug wires spontaneously combusting in quite some time.

 

[XiKeiyaZI]

Ehhh... care to explain that one in a bit more detail? I haven't heard of plug wires spontaneously combusting in quite some time.

Whoa.. I totally missed that. Bowing out until Cal is done.

 

[iguanahotsauce]

Ehhh... care to explain that one in a bit more detail? I haven't heard of plug wires spontaneously combusting in quite some time.

Not exactly sure what happened. I get off the freeway and smoke is pouring out of my engine bay so I pull into an empty parking lot and open the hood. The wires were on fire and the timing belt cover was on fire. After I got the fire out from looking at it it seemed like the first plug wire had a bad spot in the middle and started arcing probably to the valve cover and it caught the wires on fire. Scared the crap out of me

 

[Calan]

Have you thoroughly checked all the wiring and sensors to make sure there is no damage from the fire?

And... how did you put the fire out?

 

[iguanahotsauce]

Yeah I went through and checked all the wiring to make sure nothing was damaged and it's all fine and I put the fire out by dumping water on it . First I tried to blow it out but that wouldn't work and then I tried to get a fire extinguisher from the building I was parked next to but there were closed. I then realized I had a gallon of water in my car and put it out with that. I have already replaced my plug wires and my timing belt cover. It was having problems with getting bad gas mileage before the fire.

The search function for the MAF will work wonders for you.

I can't find anything on how to test the MAF. I found threads with people asking how to do it and responses to look in the chiltons manual but I don't have one

 

[Calan]

Off the top of my head, my guess is that you fried something with the water. It has a nasty way of getting into the harness connectors and causing all kinds of wacky things to happen. It could even be something as goofy as a short that changed the input impedance of an ECU input.

Before getting too carried away though, I would go through all the basics: BLT, base timing, plug gap, TPS adjustment, PCV valve, etc.. Even if it doesn't seem that something like a TPS adjustment would cause your symptoms, you may uncover something in the electrical system and at the very least, know that those items are all in good shape.

Download the FSM, and make getting a logger of some type your #1 priority.

 

[nlzn]

Sure you don't have a small fuel leak somewhere (maybe intermittent)?
Especially in the area around the timing cover (fuel rail return)..

I actually had an unknown leak from the o-ring on my AN adapter from the rail and caught my wires on fire right near the timing cover..

 

[iguanahotsauce]

I don;t think I have a fuel leak. I have checked around that area and haven't noticed any fuel. I forgot to put that I replaced the PCV as well. I don't think the water did anything because it was doing this before the water and after I changed the spark plug wires it's running the same as before. I have run into a major problem. So I went out to my car and disconnected the negative battery cable to clear any codes (my CEL wasn't coming on anymore when I turned the key to on so I thought that might fix it, which it didn't) and I unplugged my MAS connector and plugged it back in to make sure it was plugged in correctly and now my car starts, Hits about 2500 rpm's and then dies and I can't figure out why. I need to fix this ASAP as it's how I get to school D=

 

[iguanahotsauce]

So I know there are quite a few different threads about this but I can't seem to figure out what's wrong. So I go home and decided to unplug the negative cable on my batter to reset the ECU to see if it helped with the running rich problems I am having. While the negative battery cable is unplugged I unplug the MAS sensor connector and plug it back in to make sure it's in correctly. Then about 20 minutes later I go to go somewhere and I hook the battery back up and it starts, then idles high at about 2500rpm for 2 - 3 seconds then dies. It will keep starting over and over but it does the same thing every time.

 

[tips000]

possibly try cleaning your throttle body? try disconnecting your battery and waiting 10 seconds and reconnecting it...

 

[iguanahotsauce]

I will work on pulling the throttle body out tomorrow and cleaning it. I don't understand why this happened after I tried resetting the ECU. I have also noticed that my CEL is not coming on anymore when I turn the key to the on position. It used to come on for 5 seconds and then shut off but now it doesn't turn on at all

 

[XiKeiyaZI]

Sounds like a MAF issue. You should inspect the plug wiring as you could have possibly foiled a connection or pulled a wire loose from the plug. Given that I had the same issue a while back, it certainly comes off as a MAF connection issue. Compound that thought with the act of you unplugging and plugging the MAF back up and you have yourself a near certainty.

 

[tips000]

just make sure after cleaning the throttle body to put it back together... and have somethig olding the throttle open and let the stuff you use to clean it COMPLETELY evaporate... then start and rev a little and allow it to idle for a while... then after doing this and driving it a little... disconnect and reconnect the battery...

 

[iguanahotsauce]

Sounds like a MAF issue. You should inspect the plug wiring as you could have possibly foiled a connection or pulled a wire loose from the plug. Given that I had the same issue a while back, it certainly comes off as a MAF connection issue. Compound that thought with the act of you unplugging and plugging the MAF back up and you have yourself a near certainty.

That's what I was thinking. Do you think it could be a bad wire going to the actual MAF? I checked the plug a few times and everything looks fine.

 

[XiKeiyaZI]

It is entirely possible. It could even be a malfunctioning MAF. I would suggest, if possible, to grab a friend with one of these vehicles and try their MAF in place of yours and see if it acts any different.

 

[iguanahotsauce]

I tried asking everyne I know but none of them own a dsm how would I go about testingn the MAF to see if it is bad?

 

[XiKeiyaZI]

The one, sure fire way would be to start the car, unplug the MAF, and see how it effect idle. Since you can't keep the car running...let's do something different.

http://www.dsmtuners.com/forums/newbie-forum/279488-maf-mas-test-check.html

This is an older post regarding some basic signals you can check.

 

[kchaazz]

I vote for the wires going into the maf plug as well. A couple friends over the years have had this same trouble. You could fire up the car, just push on the wire gently with one finger, and the engine would die. Just try wiggling the wires around a bit Damn 20 year old wiring anyway!!

 

[iguanahotsauce]

I vote for the wires going into the maf plug as well. A couple friends over the years have had this same trouble. You could fire up the car, just push on the wire gently with one finger, and the engine would die. Just try wiggling the wires around a bit Damn 20 year old wiring anyway!!

I tried that yesterday. I had a buddy start the car while I tried wiggling the wires on the MAS and the wires on the CAS and didn't have any luck

The one, sure fire way would be to start the car, unplug the MAF, and see how it effect idle. Since you can't keep the car running...let's do something different.

http://www.dsmtuners.com/forums/newbie-forum/279488-maf-mas-test-check.html

This is an older post regarding some basic signals you can check.

When it says to back probe the Terminals of the connector does that mean while e connector is still plugged into the MAF and put the leads on my voltmeter in where the wires connect?

One other quick question

My CEL light doesn't come on anymore when I turn the key to the on position. It used to come on for 5 seconds but now it doesn't come on at all. Does that mean my ecu is going bad? Or did my light just burn out? I also tried checking for codes with an analog voltmeter and I couldn't get anything off of pins 1 and 12

 

[HAZARDINTEGRA]

If your cel light does not come on anymore I would look towards the ECM and being a issue. Before you go buying a new one i would just pull my cluster and check the bulb. It would be bad to replace the ECM for a burnt bulb.