mike98

Hi, i have a 1998 civic ex and I've been having this problem for a couple of months now.
Sometimes when i start it, it runs rough for 10-30 seconds (rpm's fluctuate a little bit) then it runs normal. Usually it happens in the morning when i go to school, but it happened a few times later when i left school too.
First I thought it might just be some moisture in the throttle body but then yesterday the engine light turned on. I went to autozone and they pulled P0301 and P1399 out, which is Cylinder 1 misfire and Random cylinder misfire, respectively.
Oh and the car had a complete tune about 1 year ago by previous owner.

I am also slowly loosing coolant but i don't know where/how... if that hepls

I've found one thread on here that had the same exact issue, but the guy never said if he fixed it or not.

thanks

pwnsauce

Sounds like a bad headgasket. Pull your spark plugs, espesially cylinder 1's, look for signs of coolant on it. You could be leaking coolant into the cylinder causing the misfire.

mike98

Thanks for reply,

Ok so i took the spark plugs off and took a couple of pictures. #2, 3 and 4 looked identical to the one on the left and #1 is the one on the right. I had to regap #1 since it looked about 15% wider than the rest. Could that have been my problem?

One more thing, should i test it with an combustion leak tester if it still sounds like its the head gasket?

thanks again

pwnsauce

well the gap couldve been the problem...does it still idle rough after you re gapped it? #1 doesnt look right at all...every plug ive seen thats been used for a while is white on the tip like 2 3 and 4.

id say do the chemical test that you set on top of the radiator. it tests for carcinogens (exhaust bubbles) in the coolant. if you fail the chem test u need a headgasket

mike98

OK I've randomly started the car about 4-5 times today and everything seems fine now after I've regaped #1 plug. I'll buy one of those combustion leak tester tomorrow and see what result i get.

Again, thanks a lot

lazlong

A compression test might be in order too, just for peace of mind.

pwnsauce

Agreed. Hopefully that fixed your problem for good, i know our cars are pretty sensitive when it comes to plugs. But id do a compression test also just to be safe.

Keep us updated how the tests go

mike98

Good news!!
I finally got the combustion leak tester in the mail and tried it and results came negative. I've also did a compression test on all cylinders and the numbers were 190, 185, 190 and 190.
Plus, ever since i regapped that spark plug the car has worked properly, so i think that was the problem.

Well thanks a lot guys, i really appreciated your help.