I recently change my O2 sensor on my 2000 chevy silverado. after replacing bank 1 and 2, I reset the it with the code reader. The check engine light went out but came back on again. Any idea?
My truck wont pass smog.The original code was PO300. It was random misfire, I was
told. I ask my buddy who is a mechanic in Arizona he advise me to change O2 sensor in
stream bank 1 & 2. And to reset it using the code reader. after changing both sensor and
resetting it. The light went out but eventually came back on again. but now the code is
PO 134 and 154. Ideas? Thanks.
p0300 has nothing to do with o2 sensors
I put back the old O2 sensor and did a tune up. Reset the computer and drove it around, the check engine came back on and so did the PO300 code.
p0300 engine misfire. On the 4.3 vortec you need to test fuel pressure leakdown to make sure the fuel pressure regulator isn't leaking causing the misfire. What items include your tune-up?
oh, this is probably a 4.8 or 5.3. for some random reason i thought it was a v6... on those a p0300 is pretty hard to find with no other codes. Usually a bad coil or injector gives a local misfire (ex: p0301). Its gotta be something central like MAF, fuel pump, vacuum leaks, coil, cam sensors. things like that.
Can't return o2 sensor cause its electronic I don't think. What is bank 1 & 2?
A o2 sensor can throw a code of p0300. I just had a o2 s3nsor go bad it was throwing code p0155, p0059 and p0050 and p0300. Changed the o2 sensor drove it all day never had a code at all. The 02 sensor regulates many things. And it can cause a misfire.
What I can suggest when you get random misfire Po 300 my experience usually it's the catalytic converter.failing I would start with plugs wires coils and Oxygen sensors. My truck has 330, OOOO miles on it. As it has aged the engine has not used oil but. The mileage and wear internallly in the engine tend to contamination the spark plugs quicker. THE Catalytic converter last approx 100,OOO before I start getting the misfire codes. MagnaFlow seems to make the best aftermarket catalytic
check you distributor and see if the gear has thinned just fixed a tuck the other day that had the same issue and the disturber gear was bad.
My uncle has a 1999 Chevy Silverado here's the reading for the truck please help
P0300 - Random/ Multiple miss fire, Generally speaking the 02 sensors are not directly connected to this code. Now depending on the engine if you get P0300 + P0132 + any other code in the 1 hundreds, yes you could say the 02 sensors could be an issue, but as the one gut said, random or mult, miss fire, Start's with / but not limited to, bad or worn Spark plugs, bad or clogged injectors, fuel pressure, reg. bad gas, bad coil, or anything in a distributor ( If it has one) plug wire/ wires, could be old and worn, thin insulation, most mechanics will tell you to start with the simple/ cheapest things first and go from there, Spark plugs, Noid lights to check pulse on injectors, make sure they are working, fuel cleaner, through intake, and fuel tank, clean throttle, even if you buy pre-gapped plugs, always check the gap prior to install!! and go from there... Good Luck
im having the same problem on my 97 chevy truck 5.7L vortech and it hat a new crate motor with 34,000 miles on it. it jerks so bad it feels like someone is trying to rip the motor out while im driving down the road. my RPM's bounces everytime it jerks, like if its trying to die and restart
ive had several different code telling me the CRANKSHAFT POSITIONING SENSOR is bad, changed 3 times. CAMSHAFT POSITIONING SENSOR is bad, changed 4 times and distributor twice. just changed out plugs and wires and still the same damn thing.
when you install new 02 sensors do you open ignition key for pcm to memorice new parts or just go ahead and start engine ?
I have a 2012 Dinali diesel I just put a brand new crate motor in it now it won’t start having gas problems
Hello I’m having trouble figuring out what’s going on on my 2002 GMC Sierra 1500. I’m getting a random misfire reading on bank 2 on all 3 cylinders. I’ve changed plugs wires and distributer and rotor. Didn’t help at all. Should I change the fuel injector next? Or what do you guys think. I do t want to keep replacing things when I don’t need to.
Hey I got a 2002 Chevy Silverado 1500 HD but I just changed the knock sensors and intake manafold gasket and but everything back and my truck still stalls at red lights and going ab 20 mph also while I’m driving my rpms drop about 500 and temp gauge goes crazy what’s my problem?
Also has a hard time turning back over
will a bad PCV cause this as well?
So my truck says it needs a map sensor knock sensor and two O2 sensor I changed the map sensor new plugs new wires and it's still hesitating when I floor it and it's still misfiring what should be my next step
I had a PO307 and PO300 code on my 1999 Chevy Silverado 5.3 and I changed the coil and plug on #7 and the PO307 went away but the 300 was still there. I checked the fuel pressure and that was good so with everything I've replaced I thought for sure it might be an intake manifold leak but since the truck is old I decided to change the injectors. After I changed the injectors the rough idle went away and the engine was quieter so I deleted the PO300 code and took it for a drive. I've driven my truck quite a few miles even smashing on the accelerator because usually my check engine light would come on when I got to 30+ mph but the code hasn't came back at all. I read that my injectors could be clogged and when I removed them they were nasty. I job took me maybe 1 1/2 to 2 hours
I’ve found on high mileage engines (GM) in this case a po300 #3 cylinder that the valve guides are to tight due to carbon build up causing the valve to stick. bad compression thus a miss fire. Now you won’t feel the miss fire if you have a scan tool you will pick it up. But the miss fire is just enough to trip a code.Causing the po 300 or witch ever your cylinder miss fire is in. The cylinder head will need to be removed the valves for the cylinder involved will need to be knurled to the maximum valve stem clearance and reassembled.
Cap and rotor.i replace mine about every 9 months. I have a cheap auto zone one but good thing its lifetime warranty. If it's really bad you can actually hear the spark jump inside the cap. I have a 2002 2500 gmc savanna. V8.also had a 2001 chevy express by got so bad van wouldn't even start. Especially on vans gets condisation inside cap.$16 and you're good to go.
Cap and rotor.i replace mine about every 9 months. I have a cheap auto zone one but good thing its lifetime warranty. If it's really bad you can actually hear the spark jump inside the cap. I have a 2002 2500 gmc savanna. V8.also had a 2001 chevy express by got so bad van wouldn't even start. Especially on vans gets condisation inside cap.$16 and you're good to go.and stop replacing o2 sensors swap them around first see if codes follow bad sensor. If it doesn't it's not the sensor
I am getting P300 after clearing the code and driving for about 10 min in a 2000 GMC Sierra. I also get P134 or P138. These lower number codes are at random but always with the P300 code. In the last 6 months, I have replaced the Y-pipe assembly with both cats (new), all four O2 Sensors, the EGR Valve, TPS, fuel pump & fuel filter, the Crankshaft Sensor, starter, ALL 8 sparkplugs, plug wires and coils. Cleaned the intake / throttle body. Had to get a new transmission (unrelated). Replaced the battery because I was getting a reading below threshold. Replaced air filter with a K&N. A week ago, I changed the fuel pump and the fuel filter - was getting 35 PSI. (Also found out that the local parts store "loan a tool" had a bad gauge.) Tested the fuel injectors w/ multimeter (12.7 - 12.9 ohms) so that was never an issue. Today I replaced the intake gaskets and cleaned out the runners in the intake. I used a wire brush and some brake clean to remove some build up. Reassembled and test drove. I got P300 and P134 about 8 to 10 minutes into the test drive. Returned home, cleared the codes and went out on the same route. Same spot, both 300 and 138 came up. Now what? Tired of this issue and nothing seems to help. This is a 4x4 half ton truck with a 5.3L engine and 4L60e Transmission. With 238,000 miles, the truck runs like a top. It should !!! Its a well maintained daily driver that sees some tow duty and light hauling. Dual exhaust, cold air intake. Nothing extreme. FYI: O'Reilys Auto parts will warranty some O2 Sensors for a short time. If anyone else is going though this, that may help. Looking for an answer or response that will help close this issue out.
