Symptoms: Rough Startup. Lasts between 1-5 seconds and then engine runs normally. Continues to run normally while driving with no misfires even at idle. Usually only happens on cold starts, warm starts are normal. Engine code reads Cylinder 1 Misfire.

Troubleshooting Steps:
Replaced all four spark plugs. Noted that Cylinder 1's spark plug was dry carbon fouled. Symptoms persist.

Swapped Ignition Coil between Cylinder 1 & 2. Code still states Cylinder 1 Misfire.

Replaced fuel injector for Cylinder 1. Symptoms persist.

I currently dumped an engine treatment bottle in the fuel tank to see if it's possibly carbon buildup, but I'm not hopeful. Any ideas for other things to check would be greatly appreciated. Thank you!

 

Exhaust or vacuum leak. I would do a smoke test or get some soapy water and go to work.

 

I thought it might be a vacuum leak, but I figured if that was the issue it would also occur at idle instead of only at startup. I'll give it a shot, thanks.

 

So I took it into the shop for diagnostics on this issue. Compression tests came back normal, but they stuck a camera into the cylinders and found coolant in cylinder 1. So it's looking like a blown head gasket. I've decided to give it a shot and see if I can replace it. I've got the service manual for my car, so I've got the torque settings squared away at least. Does anyone have any advice for what parts I'll need to remove (e.g. timing belt, power steering pump, etc.) in order to access the head gasket? Not sure where to look in this 7000 page manual to find that info lol. Any help would be greatly appreciated, thanks.

 

It's got a timing chain, not a belt.

There should be a whole section called something like cylinder-head removal.
My 1998-2002 book is like this...
Engine Mechanical
- then Engine Assembly
- - then Cylinder Head
- - - then Cylinder Head Removal

Then there's a whole lot of sections about rebuilding the rockers, inspecting the camshafts, etc... You can read that for your enjoyment some day.

Down further in the table of contents is "cylinder Head Installation".

Maybe you'll be able to hold the timing chain with a hook of some kind, to avoid dismantling the chain case. But you're that close, you might want to look at the chain guides for wear, and/or check the chain for being stretched. You probably want to avoid repeating the cylinder-head removal in the next few years if the chain is getting there...

You should look for something about the timing chain "inspection"(?). IIRC there's a way to look at how far the chain-tensioner is extended and that relates to how much wear is on the chain.

 

I am puzzled. I think first you need to find the cause if you talking about fixing. Was the car constantly overheating or was the car running rough at first start?

The rough start you were having must of been happening for a which to cause a blown gasket.

 

I splurged and got the Haynes manual as opposed to the PDF manual I found and it has all the steps laid out much nicer so I have a better visual of the necessary steps. The car wasn't having overheating issues, just misfires on cold start. According to the mechanic I spoke with this was because the coolant is in cylinder 1 and causes the misfires until it clears it out and then it runs normally. This is a 14 year old car with 220,000 miles so I'm guessing the gasket just met its maker rather than some type of cooling issue caused it to break.

 

It is important to make sure the cylinder head is flat when you reinstall with the new head gasket. Look in the shop manual, but I think the tolerance is 0.002 inch. I recommend taking it to a machine shop to have the cylinder head milled, or you will very quickly be doing this job over again.

 

I wouldn't blame it on age or mileage, as others (including myself) have older Accords with higher mileage on them. I'd think you'd notice a coolant loss if the mechanic is right.

 

I'm with you Toecutter. I have never seen it happen before without something going wrong for too long. I'm thinking since it never over heated it may have had misfires for too long causing the issue at hand. He did say it would run rough a startup (how long was it going on?) I have a 99 accord v6 with a little over 350k and no issue. I have seen when issues were ignored too long causing the gasket to fail but not just because it's old and a lot of miles.

The OP only knows the history and I'm not doubting. I'm just saying I've never seen it over the many years I've been working on cars.