P304 Only When Cold
09-10-2013, 05:21 PM
#1
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P304 Only When Cold
Title says it all. It was particularly bad a few minutes ago. Sounded like I had a horse galloping under my hood. It was almost bad enough to stall me.
Some things to mention:
-98 DX Hatch
-Bone stock D16y7
-I have been having overheating problems even though I have replaced EVERYTHING but the radiator fan and lower hose. (including thermostat, relays and switches on everything.)
-Very small exhaust leak on the downpipe. (half of a gasket burned out)
It has been doing this for a while but it was particularly bad tonight. It made my CEL flash on me instead of staying a steady yellow.
Any ideas, Honda-techies?
Some things to mention:
-98 DX Hatch
-Bone stock D16y7
-I have been having overheating problems even though I have replaced EVERYTHING but the radiator fan and lower hose. (including thermostat, relays and switches on everything.)
-Very small exhaust leak on the downpipe. (half of a gasket burned out)
It has been doing this for a while but it was particularly bad tonight. It made my CEL flash on me instead of staying a steady yellow.
Any ideas, Honda-techies?
09-10-2013, 06:13 PM
#3
Honda-Tech Member
Re: P304 Only When Cold
p0304 correct? Thats a misfire on cylinder four right? If so It could be a multitude of things. Are you losing coolant? If your overheating you could have a head gasket leak into cylinder 4 causing it to misfire and cause your overheating. Pull the plug and shine a flashlight down into the cylinder. If it looks cleaner than the others it could mean coolant is leaking into the cylinder. Also pull the distributor cap and make sure all four points under the cap are still present preferably cylinder fours contact.... The bad head gasket idea would make the p0304 code and the overheating relate, but if their not related the misfire code could be caused by many things.
Only when cold is strange though. Maybe there is low compression on that cylinder and once it warms up it has an easier time igniting the mixture. Also a head gasket leak could seal once the engine is warm and has expanded...(that ones just a guess though)
Only when cold is strange though. Maybe there is low compression on that cylinder and once it warms up it has an easier time igniting the mixture. Also a head gasket leak could seal once the engine is warm and has expanded...(that ones just a guess though)
09-10-2013, 06:42 PM
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Re: P304 Only When Cold
p0304 correct? Thats a misfire on cylinder four right? If so It could be a multitude of things. Are you losing coolant? If your overheating you could have a head gasket leak into cylinder 4 causing it to misfire and cause your overheating. Pull the plug and shine a flashlight down into the cylinder. If it looks cleaner than the others it could mean coolant is leaking into the cylinder. Also pull the distributor cap and make sure all four points under the cap are still present preferably cylinder fours contact.... The bad head gasket idea would make the p0304 code and the overheating relate, but if their not related the misfire code could be caused by many things.
Only when cold is strange though. Maybe there is low compression on that cylinder and once it warms up it has an easier time igniting the mixture. Also a head gasket leak could seal once the engine is warm and has expanded...(that ones just a guess though)
Only when cold is strange though. Maybe there is low compression on that cylinder and once it warms up it has an easier time igniting the mixture. Also a head gasket leak could seal once the engine is warm and has expanded...(that ones just a guess though)
09-10-2013, 09:54 PM
#5
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Re: P304 Only When Cold
You're losing coolant, overheating, and have a miss? Sounds like a classic damaged head gasket. Do a compression test, and a block test. Tools for both can be rented from your local chain parts store.
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