Hi everyone, first post.
I’ve had P300, P301, etc. cylinder misfires. I have a VTEC 2.4 4 Cyl engine with 90K miles, original owner.
My mechanic changed the spark plugs, all four, and ruled out the coils. Check engine light went back on. I brought it back, he looked again today, said he saw liquid in one cylinder, the other three are dry. I forgot to tell him today that this morning upon starting the car, there was a ton of white smoke, and it took forever to heat up the interior. Is this a blown head gasket? Honda dealer told me to junk the car and get a new one. Should I have my independent mechanic look at the head gasket and give it a shot? Otherwise, is it off to a used engine?
Thanks so much for reading,
Hi everyone, first post.
I think having a second opinion would be warranted. It sounds like the head gasket is blown but it could also be a cracked block. Did the engine ever overheat that you know of? If it’s a blown head gasket I would have the car repaired. A 2004 Honda with 90K is still in it’s childhood so to speak. I would get a used engine if the block is cracked. Don’t junk this vehicle yet as it has a lot of life left in it. I think the dealer just wants to sell a new vehicle.
Offhand, it does sound like a head gasket problem. What should be done (or should have been done when the plugs were out) is run a compression test on all cylinders; even on the cyls. that are not affected by a head gasket breach.
The purpose of this is to determine if there is piston ring damage throughout the engine, which means time to rebuild or replace it.
A vacuum test, hydrocarbon test, etc. are additional means to verify a head gasket fault.
All of these tests should be done to make double sure of the problem.
A head gasket replacement only is a viable repair IF the engine has not suffered some chronic or very severe overheating and IF the compression tests on the rings show good.
With a ring problem you’re better off finding a used engine; and praying the used engine is good.
With any expensive repair question(you are posting) get a 2nd opinion.
On Wednesday, April 21, I had an oil change and front brakes done. Two days later, I noticed a vibration after starting the car for about three seconds, before smoothing out and sounding normal. It happened once again after starting the car, and then in the afternoon, the Check Engine Light went on.
I brought the car to the Honda dealership for service, where they brought me into the shop and said I have multiple cylinders misfiring, and one of the spark plugs had a liquid residue on it, which appeared to be oil, versus the others which were clean. They conducted a compression test, with the readings as cylinder 1: 185 psi, cylinder 2: 215 psi, cylinder 3: 185 psi, and cylinder 4: 185 psi. A leak-down test was not done to possibly pinpoint whether it was a ring/valve/head gasket issue. They mentioned something regarding the head gasket, but were more convinced it seemed that the engine was pretty much done. They recommended I look into a used or new engine, or trade the car in and look for a new one.
The plugs were changed and coils were determined to not be an issue, and the light went off. But now, the light is back on, I have the same codes: P300, P301, P302, etc. Tuesday, I took the car to work, and upon starting it up after having it sit outside overnight, a substantial cloud of white, sweet smelling smoke came out of my tailpipe. My heat inside the car also took longer than usual to work. The car drove fine, but the startup had the same vibration I described. Starting Wednesday, I carpooled with my wife, and have not driven the car.
I have not noticed the car overheat. The symptoms I?ve experience again are:
? Vibration of car upon start up
? Loss of heat, or longer time to heat up interior of car
? White smoke from tailpipe, with sweet smell
? Check engine light stays on
I have taken good care of the car, never abused it, and change oil regularly.
A friend of mine who does work on Audis and VWs is guessing if the residue was indeed an oily residue inside the cylinder, maybe I have a leaking valve. He recommends doing the leak-down test as well to verify, then pull the head and get to work.
Certainly get a second opinion, but it does sound like a headgasket. IF the engine otherwise checks out ok as ok4450 noted, I’d get it repaired.
If it doesn’t then your only option to get the car running again is a new or used engine. But watch the cost carefully. An engine replacement could cost a good % of the resale value of your car. The 2004 Accord wasn’t known for having a robust transmission, either, so I would make sure that gets a proper inspection before and during the replacement to make sure you aren’t throwing potentially thousands of dollars at a car with a failing transmission. If that is going, too, I would NOT waste any money on the engine.
I believe this problem should be investigated a bit further by doing a hydrocarbon test, cooling system pressure test, etc.
A leaking valve will not cause any smoke but a leaking valve seal could. (usually blue)
The compression readings of 185 PSI are great. The one that sticks out is the 215 cylinder as that is actually too high.
It’s possible that this cylinder pressure is being raised artificially higher by coolant seeping into that cylinder, which will of course cause white smoke and rough running/misfire due to coolant diluting the air/fuel charge.
(The loss of heat, etc. could be due to a thermostat that is stuck open)
My gut feeling is that the engine is likely ok due to the compression readings and a simple head gasket replacement should be enough.
Something else to consider is the possibility that the head gasket is fine and this problem is due to a leaking intake manifold gasket. My memory is very fuzzy on this but I think (?) there is a coolant port located in the intake gasket by the No. 2 cylinder.
If the head were to be pulled it might be a good idea to pull the intake manifold by itself first and verify the problem is not in the intake gasket. Knock on wood. Hope that helps.