Cyl 2 and 3 missfire
 

My friend has a 98 camry. 4 cyl. my scaner shows missfire for cyl. 2 and 3. and a random missfire. i replaced the plugs because they need to be, fouled out. i tried replacing the coil pack for 2 and 3 thinking that was i, but it was not. still missfire. the only other thing i can think of would be fuel injectors? o2 sensor? but wouldnt the O2 cause just a radom misfire? not a specific cyl missfire?? how do i test the fuel injectors other than switching them with cyl 1 and 4? any suggestions would be awesome. thanks

The coil pack needs a trigger signal which it may not be receiving. This is what they call call the "lost spark" system in which two plugs are fired at a time but only ONE cylinder has fuel/air. Plugs get twice the wear but it makes for a simpler system and they seem to last OK anyway. You should look further back into the system than the pack. Time to look at the shop manual. i lent mine out, I'll get it back and take a look if you don't have one handy.

Pull the plug 2&3 wires, plug a couple of plugs into them with a gap somewhere near right (you really only need test one) pull the fuel pump fuse so you don't drown the converters, crank, and look for spark. You are leaving a plug in 2 and 3 so you don't blow fuel/air all over the engine compartment while having two spark plugs (maybe) zapping away. You need to GROUND the threads of each plug to the block with a wire, hose clamp, whatever. Stay away from the alternator and injectors with that ground. If there is no spark and you have already swapped coil packs then I would suspect the "firing signal" from the ecu, or maybe something like the crank position sensor. Let us know what you find.

I have a simmilar situation with my 1997 Camry (230 thousand miles) but I have a missfire on #1 and 2 cylinder.
When this happen I just put a gasoline to my car and probably I did not seal a fuel cap appropriately (like a half turn) and went straight to the car wash. My engine was on idle. When I got out the check engine light started blinking or remain on constantly AND my engine was losing a power.
So far I know that has misfire on cylinder #1 & 2, and codes P0300, P0301, P0302 are returned. When car is parked and RPM are higher than about 1200 then all cylinders are working but as soon as I lower RPM or try to drive everything goes bad again.
In meantime I realize that a clear air hose was broken, so I replaced but it did not help.

I am going to replace spark plugs today, but I have a feeling that this problem is similar to yours?
Did you fix the problem? Someone can help?

You may have to change all the PLUG WIRES because they have absorbed some water. Start the car up at night or in a dark place, open the hood, and look for flashes around the plug wires. NGK makes great wires (though expensive) That must have been some powerful car wash.

With that milage the factory wires are probably worn out. They may have been replaced with Brand X already, which may have ALSO worn out, but unless you use good quality wires, they won't last as long as the Toyota wire. They don't actually wear out, but the insulation which should be good for 30,000 volts at least, starts to crack and let moisture in. Water isn't a very good insulator.

Thanks a lot for the advise... I actually fixed the problem last night. You were right, it was a wire. I replaced them like a 50,000miles ago.
Everything works fine now....
Thanks

Glad you fixed it. Imagine the parts a dealer service writer on commission would have thrown at it. I should have added that a spray bottle of water squirted at the wire area at night can show up the bad wires. THe voltage to fire the plugs goes UP as cylinder pressure rises so an engine may idle OK but act up under load.

Have a couple of codes on a 97 camry 2.2 4 cylinder they are p0300 and p0302 I have replaced plugs and wires lights are of but I still have a misfire, could this be the coil packs?

P0300 is a general misfire code. P0302 is misfire on cylinder No 2.

Could be a bad No 2 coil. Follow the No 2 and 3 spark plug wires back to the No 2 coil.

If possible swap the No 1 and No 2 coils. Then clear codes and wait for check light to return. Check for P0301 or P0304 as codes follow the bad coil.

Use an ohm meter to check resistance between the two spark plug wire terminals on each coil when the engine hot and cold, then reply back with readings.

Check ohm reading between primary and secondary electrical connections of each coil engine hot and cold, and reply back.

When checking coil note brand name listed as Toyota used two brands, AISAN and Diamond brand.