I have had a P0172 CEL code for a while now, but the car has been running fine.... until now. I have read through the forums on this code and will be looking carefully for vacuum leaks and will replace the short term O2 sensor. From all that I have not heard anything about this problem actually causing the car to die, which is what has happened to me multiple times now. I have been lucky to get it started the last couple times, cranking over and over and having to floor the accelerator to get it to start. I can hear the fuel pump kicking on so I think it is getting fuel. Could a bad O2 sensor cause this behavior?

 

What year is the car?

 

Sorry for the lack of info. My car is a 1998 with 124k.

 

I would check the fuel pump relay.The fuel pump relay can stall the car then activate again.

 

Thanks for the quick reply! Is there a way to test the fuel pump relay, or do I need to just replace it?

 

You can open it up and inspect the solder joints and see if they are cracked.

 

I inspected the fuel pump relay today and it looked perfect, no cracks in the solder or any other perceivable problems. Even when I was having difficulty starting the car I could still hear the fuel pump kicking on when the key was turned. Should I go ahead with the replacement of the O2 sensor? I agree that it seems like the car isn't getting fuel, or maybe it is getting too much. Could a faulty O2 sensor cause this? Any other suggestions would be appreciated. Thanks.

Drew

 

The O2 usually will not cause a stalling issue unless it is dumping way to much gas in.
But that will usually make it run so rich it will puff black smoke out the tailpipe at all times.

When it dies does it feel like it is running out of gas?

 

When it dies it does not stutter. It simply shuts off, power steering goes, etc. It first occurred when I was doing about 45 and deccelerated. It started right back up. Later that day it had a small "hiccup" when slowing down and taking a right, but kept running. After parking I tried to start two hours later and it wouldn't start.

 

Sounds like ignition then either spark or something like that.

 

Ok. I will ckeck the plugs and wires. Not really sure how to check if the coil is working, but if it is cheap enough I will just buy a new one.

 

Next time it will not start make sure you have power going to the spark plugs.

 

Ok. So I think I failed to realize an additional code on the OBDII. It reads the P0172 (been around for a while) and the new one P0303. I checked all the plugs and they looked ok. What else could this be? Would a MAF explain the misfire and the bank 1 too rich? O2 sensor?

 

How old is the dist cap rotor and wires?
How old are the plugs?
What type of plugs?

Any vacuum leaks?

 

I bought the car 18 months ago with 113k. I have not done a tune up yet, 124k, but I checked the plugs today and they said Volvo on them. I think I should order an OEM tune up kit and replace everything, it is probably time anyway.

 

Do you happen to know a resource where I could find the vacuum diagram for my 98 xc? I want to make sure I check all the lines.

 

Unless the hood was changed there should be one on there.

 

The tune up kit from fcpgroton arrived today and I replaced the plugs, wires, rotor, and distributor. In order to do so I removed the air cleaner. After replacing everything, I started up the car without the air cleaner hooked up in case I needed access still. The car was running pretty rough at idle still, and now it generate a code of p0301 cylinder1 misfire instead of cylinder 3 misfire. I am kinda lost at this point. I took a look at the vacuum lines, but didn't have much light left. I will take another look tomorrow. Any suggestions would be appreciated.

 

Maybe it is time for a compression test.
Also did you mix up any of the wires on the cap?

 

Sorry for the long gap... I finally got to take a vacation. I have checked all the wires and they are routed correctly. I was able to drive the car around for a bit without it dying, but I ended up with a P0300 code - random/multiple cylinder misfire. I listened under the hood while it was running and intermittently I could hear a tapping noise and pinpointed it to the vacuum can. When I touch it I could feel the tapping too. I have looked closely and am not able to find any vacuum leaks. Could this tapping be a result of a misfire or is it a cause? I have not had time to run the compression test. Is it possible that the coil is going bad intermittently? I have only experienced it either working or not in the past on other cars. Also, would it be worthwhile to replace the fuel filter in case it is a fuel issue. What about injectors? I guess I am wondering what order I should be checking all of these things. I am trying not to simply throw parts at this. Any suggestions would be appreciated. Thanks.