Cylinder 2 misfire at 1500-1700rpm please help diagnose

Again... I will say this it's the egr cooler. . It's clogged.. When the engine is cold.. The egr valve is closed... When the temperature is set the egr opens.. The computer makes adjustments if it doesn't get the proper egr gas.. Then the cumbustion if now miscalculated.

 

That could occur if egr passages in the intake manifold are unequally clogged.

Soot is more likely than "suet," unless the car has been fueled with animal fats.

 

If there was a CEL I would agree. Absence of EGR flow would normally trigger a CEL. If there is no EGR flow, the fuel map is going to revert back to the no flow fuel map.

 

Not always the case. I've seen plenty of forums describing your issue. With no check engine light. The egr cooler was clogged enough to give your symptoms. I can bet you it's clocked and either needs to be cleaned or replaced.. It's a design flaw because it is located before the cat. Unlike the gen 4.

 

Okay so we are dealing with different issues. Occ is to help the start up knock from cold weather the water and blowby built up in the intake. That can cause headgasket failure.. Egr cooler and valve uses exhausted fumes that are quite dirty to cool the cylinder and help with mpg. But because of a design flaw the cooler must be cleaned every 60 to 100k.

 

Oh and YouTube egr cooler by nutz and bolts. It's a great easy to understand walk through how to diy. I've cleaned mine with oxyclean and purple power degreaser. I cleaned mine at 70k was pretty clogged now at 99k still runs like brand new.

 

Burning oil through stuck piston rings produces similar results as burning oil through PCV.

Actually, you're burning 1q engine oil every 2k miles somehow with OCC. That's probably worse than burning 1q of PCV liquids since some of that liquid is water and gasoline.

Pixel XL ?

 

It depends.. Remember water is not compressible or combustible, so that's where I believe headgasket failure happens on the prius. Water keeps getting sucked into the cylinder and that knocking start up noise perfect example of that. Oil and gas vapor ignites. Sure leaves behind carbon but I guess pick your poison.

 

Right, my point being that in an oil burning engine that has an OCC - carbon buildup in the cylinders is still occurring. Probably best to correct the oil burning also. Correcting oil burning should help lesson the rate of EGR build up. Carbon buildup may be causing OPs P0302.

Pixel XL ?

 

Did you remove the intake manifold at that time to clean the EGR passages?

Yes.

 

Diagnosing a single cylinder misfire requires you to focus on causes which can affect a single cylinder only.

If you do not have coolant loss, it is unlikely that it is a head gasket issue. Your compression test confirms that compression is good and even.

A valve sealing issue is most likely to show up when cold, but it is not impossible for it to show up under other circumstances. A leakdown test would be your best way to confirm.

The EGR system will more than one cylinder, not just one. But I suppose that if one of the channels in the manifold was clogged it could affect only one cylinder.

Edit: did not read the original post.