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Sammwell

P0300

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Hey Everyone,

 

so when I first got my path about a week and some change now. I first scanned the car and got codes:

P0100

P0325

P0304


since then, I replaced the

maf sensor (terribly clogged & dirty.)

Spark Plugs

Spark Plug Wires

Distributor Cap

Valve Gasket Seals

Throttle Body Gasket. 
 

after doing those, the codes went away except for knock sensor (P0325). Which was a given since I didn’t do anything to that. Than just 2 days ago, the car threw a CEL, and I scanned it and P0300 & P0171 popped up. I cleared the code and the p0300 came back but now P0171. Than today, P0171 popped back up. 
The car idles a bit jittery in intervals. It doesn’t drive bad, but the misfires seem to happen at idling. 
I read threads that’s mentioned doing a tune up (which I’ve done as mentioned above) or checking for any leaks. I sprayed some break cleaner on the hoses to see if it causes any spikes in rpm, and nothing. All sensors and hoses are connected. 

 

Can anyone steer me into the right direction on what could have possibly caused these codes to pop up, as I seem to be stumped. 
 

any help would be greatly appreciated!

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Hit all the vacume lines.   
 

 

Blow out caroal line from rear.  
 

charcoal in box breaks up goes down the tube.. but I think that’s a different code.  
 

 

I had vacuum codes I’ll I replaced all of em.  There was a tiny pin hole in one on the octopus near the MAP sensor 

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Misfire code and system lean code, both point to a fuel supply problem so start there. I would change the fuel filter for starters,  worst case is that it delivers the same amount of fuel! The misfire could be anything from electrical to mechanical to electronic but the usual process of elimination of possibles is more important now. 

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Hey Mattmill91, thanks for the response! I did hit all lines and there were no changes with rpm spikes or anything weird. 
 

Just a thought, but would the timing from the distributor throw these codes? 

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The lean code takes priority since a lean condition will cause a misfire. I am more inclined to think an air leak than fuel delivery since the misfire is happening at low engine speed. 

Do a visual inspection of the intake hose and the breather hoses. The intake hose has a tendency to crack in the bottom of the pleats where it is not as noticable. Cracks in the intake hose and or the breather hoses will skew things since there will be more air drawn in than the MAF is measuring.

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Solved! There was a hole on the intake hose underside right by the throttle body. When my friend was cranking the car to turn on after timing the dizzy, I heard a loud pop and saw a flame come out from that area. Probed around, and saw it Cracked the hose right down the middle. I guess upon checking for leaks, we didn’t notice that, and spraying the hoses didn’t do anything since it was on the very underside and close to the throttle body. Easily overlooked as Mr_Reverse mentioned. Drove it around a bit and no codes yet. Sure hope that fixes things (for now). 
 

thanks to everyone that chimed in and helped out. this is honestly the first car forum I’ve been on that has been very proactive and quick with responses!

 

 

Edited by Sammwell
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On 11/25/2019 at 9:49 PM, Mattmill91 said:

Blow out caroal line from rear.  
charcoal in box breaks up goes down the tube.. but I think that’s a different code.  

 

How do you blow out the charcoal line? The charcoal boxes are in the rear near the spare tire right? And if I recall, the vent is a tube that points down?

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How do you blow out the charcoal line? The charcoal boxes are in the rear near the spare tire right? And if I recall, the vent is a tube that points down?
Depending on what year you have there is a blowout line on the driver side engine bay. close to the master cylinder it even has a cap to unscrew to hook up an airline to blow it out. Here's what the FSM has listed for 97 vg33e. On the diagram it shows what line goes to the evap canister that's the one you will blow out95ca2943133491c5de1055b5b6f3e942.jpg

Sent from my SM-S367VL using Tapatalk

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If you are talking about the the green cap, that is the evap service port for attaching a smoke machine to look for leaks in the evap system. It is very low pressure 1-2 psi and higher pressures can do damage. 

 

The only way to clean out the lines is to disconnect at both ends and then flush them out. If carbon is in the purge or vent lines, the canister must be replaced because it is damaged internally. 

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Something else a lot of people don't know is whenever you're filling your tank up once it shuts off automatically letting you know that your gas tank is full don't continue to top it off because what happens is when you overfill your tank all that gas in the filler tube goes to your canister that's what breaks down the charcoal inside of it making it wet brittle.

Sent from my SM-S367VL using Tapatalk

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So I spoke to soon..after fixing the 2 codes mentioned in the initial posting of this thread, I went to randomly scan the car to make sure everything was good. I saw a new code P1448, which is the Evap Canister Valve. My (stupid) question can a gas cap throw this code off? I ordered this valve just in case, but things seems to be taking on a domino affect..

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I would have to look it up, but I believe the 1448 is a fault in the circuit for the valve. So probably the valve. Leaking cap usually sets a P0440 and or P0445 for a system leak. 

 

You can test it by removing the valve and using a couple of jumper wires to the battery. It should make a solid click as it closes with power on. With it on, try blowing through it, it should not allow you to blow through it. Off should be open and blow through it easily. 

 

I have replaced a few of the vent valves because they will get dirt and water in them preventing them from sealing and a couple simply seized and wouldn't move. 

Edited by Mr_Reverse

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