P0303 cylinder 3 miss fire on start up

Does it ever have any white/blue smoke out of the tail pipe?

 

Yes it does, and it smells on start up

 

https://www.yourmechanic.com/articl...inder-3-misfire-detected-by-spencer-clayton_2

 

It doesn't overheat at all?

 

Did you peel the paper off the end of the straw? It needs to be unpeeled. The paper needs to soak up the liquid.

 

Next time when you're driving the truck. Do you notice blue smoke coming out of the tail pipe, when accelerating from a stop light? If you see smoke, coming out during acceleration from a stop it's the valve stem seals is worn out and letting oil into the cylinder.

 

Just checked the compression on cylinder 3 and the two other cylinders on the same side, cylinder 3 was about 25 psi less than the other two cylinders. My truck hasn't been over heating what So ever. I couldn't find the paper straws so I made my own by rolling up a piece of paper and just taping two sections of it so it would stayed rolled, it didn't really soak up any liquid at all, just scraped what looked to be burnt oil of the piston head. I have noticed a white/blue tinted smoke before on start ups but it is the faintest blue and goes away after running a short amount of time, the exhaust does smell funny.

 

Nitrous oxide?

 

Doesn't sound to good. 25psi difference is substantial. Is the inside of the engine normal and not all slugged up? What were the compression numbers?

 

I checked while the motor was cold and and the 2 cylinders that haven't been giving me trouble were at 175 psi and cylinder 3 was at 150 psi. Cylinder three, when I did the paper straw test, the straw scraped some black grime out, when I cheacked another cylinder there wasn't any grime to be scraped out

 

Could you test all Cylinders to get a baseline number. Testing 1-2 gives inconclusive results.
A Co worker he had an LX450 Mil light on. And service writer were not going to pay him to do proper cylinder compression test or leak down test. So he took compression reading on 2 cylinders and reference the reading to the Lexus manual. And the number Lexus gave was 180psi. His reading of the 2 cylinder were a lot. Lower then the books and he sold cylinder head gaskets. It was a of repair works

 

Other thing to do is pour a little bit of down the cylinder to do a dynamic compression test. If the number increases we know the piston rings are OK

But you mention if the car is parked for a while after driving. And upon start you notice blue smoke. It's the valve stems seals are worn and needs replacing

 

A little bit of oil.
And it's the other way around. If compression increases the rings are the no good.

 

Cylinder wall may be scored from debris introduced when repairing plug hole threads. How is blow by?

 

Hi guys, I've just started school so I had been lagging on this. I ended up taking my truck to a dealership and they were able to look into the cylinder and they found that I have a cracked head

 

https://sandiego.craigslist.org/csd/pts/d/toyota-tacoma-core-heads/6311061477.html

 

If you're in SLO and need a head call or stop by Asian Auto. Gary is a reasonable guy and a specialist in all things Toyota.

https://www.google.com/search?q=asi...j1j7&hl=en-US&sourceid=chrome-mobile&ie=UTF-8