ive recently purchased a 1997 honda accord v6 for 400$. yes i know yay.. good deal. but there has been a few issues with it. most of which ive fixed already. but the one that boggles me is the issue with a cylinder 5 misfire detection from the diagnostic. so im guessing its either an issue with the plugs, wires, ignition cap, or fuel injector. i did a dry test on cyl 5 and yes for sure theres an issue with it. also tested the spark against the block and yes there was a spark. so now the issue is either spark plug or injector. i changed all the plugs and went to the junk yard for a couple of fuel injectors. i put in a new injector, it runs well for about 8 mins then when i start putting the covers back on and the car warms up a bit, it starts bogging a bit and the check engine blinks with a misfire code again. any help on this matter would be greatly appreciated.

 

did you run a compression check on cyl 5? also, pressurize the cooling system to see if you have a coolant leak/bad head gasket. the leak may be showing up after the engine warms up.

 

sorry about the most likely uneducated question. but how would i go about running a compression test and pressurizing the cooling system?

 

to check compression, either rent or buy a compression tester. it's just a pressure gauge. you thread a fitting into the spark plug hole and attach the gauge. turn the engine over and it reads the cylinder pressure, check all cylinders, and if cyl 5 is much lower, you have a problem with a valve or rings or the compressed air is going into the coolant chamber. this would mean a blown head gasket. you will also have to rent or buy a radiator pressure tester and attach it to the radiator in place of the radiator cap. pump up the pressure (like a balloon pump) to the standard pressure of the rad cap. watch to see if the pressure drops and look for the leak if it does. if the coolant is leaking, and it's going into the combustion chamber, you may not see it. no matter what, you have a leak somewhere if the pressure is dropping. i'd run the cooling pressure test first, since it is easiest. also see if you have any coolant on the #5 spark plug.

 

1st check compression...Find out if its a compression leak or a ignition problem..
How does the Distributor cap and rotor look? Even if you have spark it could be ground out in another place.
Compression leak could be from bent valve, blown head gasket, crack head, fired piston rings.
Ign problem could be Cap, rotor, Spark plug wires, Distributor or even the Ecm its self.
If you have a blown head gasket you will want to try a block tester, or remove the coolant cap and see if it comes pumping out. That if it really bad. I would inspect the the cap and rotor first. Look for bad exposed wiring.

 

hmmm interesting, i will check the cap and rotor. i thought i was safe on the ignition if there was a proper spark coming from the end of the wire when i put it near the block. i guess thats an improper way to test it. im just really hoping that is the issue. i find it odd that it runs well then suddenly starts acting up when its first started.

 

ok so what i did was change both the cap and rotor to a new one. gp sorensen from advanced auto parts. the car fired up quite smoothly. i waited about 8 minutes and as the car started to warm up i noticed that the check engine light is starting to blink again. checked the scantool and its the same code again. cyl 5 misfire/ multiple/random cyl misfire. im awaiting my pressure gauge from being sent online to do a compression test. im really hoping this isnt going to be a big issue. is there anything else i can check to make sure its anything else but a leak in the block or blown gasket.