dundfaukus

I have a 1998 Civic DX(no vtec, just SOHC) that ran perfectly up until last Sunday where I am driving on the highway and began to hear a faint clicking noise. The noise progressively got worse and I noticed that I was losing power(could not go over 60mph, then 50mph,etc). Car did not overheat or anything that would lead me to suspect something was actually going to go wrong.

Stopped at a gas station and noticed a bad ticking/knocking sound coming from engine. Towed the car home and check out everything I could without ripping head off.

Found that exhaust manifold had bad crack so i replaced that, adjusted valves to be within spec, and made sure the timing is all lined up at TDC.

Car has trouble starting up(must give full throttle to get it going), once on the car idles badly and the loud tapping noise is still there. I want to get opinions before taking the head off...

Thanks in advance...

thumper64

Maybe bad ignition or valve timing? Maybe you have vacuum leaks, burnt valves or bad deposits. Checking the timing shouldn't be hard, and you could run a can of seafoam through the intake per listed instructions.

na+b18c_hatch

almost sounds like you didnt have any oil in the engine. did you check that?

also you might try popping off your distributor cap and shield and check the coil and the ignitor inside. sometimes you can get some corrosion in there and it wont let you get a good spark. just a thought, its not hard to check.. the hardest part is bumping the ignition to be able to get to the rotor screw, it can be a little touchy.

dundfaukus

I change my oil quite often, matter of fact there was about a week old oil in there before this mess happened. Nothing special done, just the same 10w30 I've always put in.

I looked at the ignition, spark is there and I replaced the rotor/cap to be sure...

na+b18c_hatch

when i replaced the ignitor and coil in my type r my car died shortly after, i didnt know wtf was wrong with it. so i took the distributor apart again and it turns out the connectors to the ignitor were loose and had fallen off under acceleration.

was the timing off the first time you checked it? could have jumped and bent some valves..

dundfaukus

Timing lines up fine the first time and even after I reset it to see if that was the issue.

It sounds like the pistons are slapping the valves, someone mentioned it my be a broken rocker arm...I have no idea what that looks like...everything seems tight to me.

na+b18c_hatch

yeah you'd definitely have to take the head off to check for piston slap- you'd be able to see metal-metal contact points on the pistons and the valves.
did you over-rev it or anything like that? (be honest, we're trying to help and we need the facts lol)

dundfaukus

Oh no over revving, I drive my car within limits...no racing or anything like that.

I did pull the head off finally and I see no signs of chips or bends in the valves...would it have to be taken to a machine shop because it may not be viewable to the naked eye?


Modified by dundfaukus at 11:09 AM 7/15/2008

na+b18c_hatch

thats pretty damn wierd if you ask me. do you have any mechanic friends that could double check it before you spend bunches of money paying someone else to diag it?

OMGWTFBBQ!

Are you 100% sure the tapping is coming from the head? If its coming from the block it may just be time for a new, low mileage D-series motor. Those engines are so cheap its almost always cheaper to just replace the entire engine if youre doing anything other than routine maintenance.

dundfaukus

Actually I did take the oil pan off and check for bad bearing or excess metal shavings that would indicate that it might be my bottom end...all that seemed fine.

na+b18c_hatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by OMGWTFBBQ! &raquo;</TD></TR><TR><TD CLASS="quote">Are you 100% sure the tapping is coming from the head? If its coming from the block it may just be time for a new, low mileage D-series motor. Those engines are so cheap its almost always cheaper to just replace the entire engine if youre doing anything other than routine maintenance. </TD></TR></TABLE>

werd. if you spun a rod bearing it could be the sound of rod-knock. thats never fun. might as well swap in a b16