I searched with several criteria and found that people were who were having similar noises were told to check valve clearances. The only weird thing about my situation is that the noise comes in (at least noticably so... it's somewhat more faint otherwise) when I'm accelerating the car. So here's a summary of the condition of the car and also the problem/symptoms:

1. 1996 Integra LS (b18b engine), stock @ ~148,000 miles. Oil level, coolant levels are fine. Engine temp is fine. No CELs. Idle is slightly lumpier than it used to be. I rev the **** out of it once a day Timing belt was changed about 30,000 miles ago, and valve clearances were adjusted at that time. Crankshaft pulley also was changed at that time (since it broke).

2. There is a rattling/chattery noise out of the engine bay when the car is accelerating. The noise is audible from outside of the car and also from the inside. The noise is less prominent when the car is not in gear and the engine is revved in neutral. The noise seems to come on as soon as the throttle pedal is depressed, and stays until I let off. I popped the hood and it sounds like the noise is coming from the intake side of the engine, under the valve cover. EDIT: Also, the noise is directly proportional to RPM (more revs = higher frequency rattle).

3. Car drives just fine. No loss of power or other weirdness to speak of.

TIA


Modified by mdpalmer at 2:14 AM 3/19/2005

 

lumpy idle? chatter under valve cover? Bent valve is my bet, but it must not be very severe...its still running. Might not be, though. Does the sound speed up with the RPM or is it just a constant ratlle no matter what RPM the motor is turning?

Take off the valve cover and have a quick look.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by notstock93 &raquo;</TD></TR><TR><TD CLASS="quote">lumpy idle? chatter under valve cover? Bent valve is my bet, but it must not be very severe...its still running. Might not be, though. Does the sound speed up with the RPM or is it just a constant ratlle no matter what RPM the motor is turning?

Take off the valve cover and have a quick look.</TD></TR></TABLE>

Thanks for asking for clarification. I forgot to mention in my post that the rattle goes up/down in proportion to revs. What do you think? I'm going to look at it tomorrow morning. Thanks

 

It could be a crapped valve, or maybe something with the rocker. I don't know. It could even be a bad injector, but the idle would be like a Harley if you were firing on 3 cylinders. So...scratch that. Im thinking thinking is written form now....

My guess is a valve is way out of lash, or at the worst, a valve is bent and needs replacing.

EDIT- Im assuming you've checked for exhaust leaks causing the noise?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by notstock93 &raquo;</TD></TR><TR><TD CLASS="quote">It could be a crapped valve, or maybe something with the rocker. I don't know. It could even be a bad injector, but the idle would be like a Harley if you were firing on 3 cylinders. So...scratch that. Im thinking thinking is written form now....

My guess is a valve is way out of lash, or at the worst, a valve is bent and needs replacing.

EDIT- Im assuming you've checked for exhaust leaks causing the noise?</TD></TR></TABLE>

Yep. Triple checked for exhaust leaks. Not a thing. One thing that I didn't make so clear either is that idle is really pretty good... I'm just being paranoid about it (although it *is* a slight bit lumpier). The condition has not changed over the last few days... I'll check clearances and whatnot tomorrow and repost my findings

 

I took off the valve cover and had a look at the valvetrain; everything looked OK. I didn't have an opportunity to check the valve lash, since I couldn't find a 19 mm socket in my toolset (to turn the crank pulley).

However, I was alarmed to see that the cam gears were pressed up against a plastic cover (in the Helms it's called the "back cover"... see page 6-7). It would seem that when the engine is running that there is constant rubbing of the cam gears on this cover. THere were some obvious signs of wear on the cover... due to the gears grinding against it.

Has anyone ever seen this kind of thing before? Why would it happen at all? I didn't have time to try removing the cover, since it started raining... I'll look into this more and report back. In the meantime, any thoughts on this?

 

bump for people who know more about engines than I do

 

TTT

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mdpalmer &raquo;</TD></TR><TR><TD CLASS="quote">I took off the valve cover and had a look at the valvetrain; everything looked OK. I didn't have an opportunity to check the valve lash, since I couldn't find a 19 mm socket in my toolset (to turn the crank pulley).

However, I was alarmed to see that the cam gears were pressed up against a plastic cover (in the Helms it's called the "back cover"... see page 6-7). It would seem that when the engine is running that there is constant rubbing of the cam gears on this cover. THere were some obvious signs of wear on the cover... due to the gears grinding against it.

Has anyone ever seen this kind of thing before? Why would it happen at all? I didn't have time to try removing the cover, since it started raining... I'll look into this more and report back. In the meantime, any thoughts on this? </TD></TR></TABLE>

I changed out my cam gears and it rubbed against the cover too. I just removed the plastic cover and no more problems. I thought something was broken cuz of the hidious noise it was making but came to be that its the plastic cover

 

myu engine sounded like that when i spun my rod bearing iwould drain the oiland see if there was any metal in it if its not the cam gears.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drowzysleeper &raquo;</TD></TR><TR><TD CLASS="quote">myu engine sounded like that when i spun my rod bearing iwould drain the oiland see if there was any metal in it if its not the cam gears.</TD></TR></TABLE>

I'm getting worried... now that I think about it, it seems as if the noise is coming from the bottom end and NOT the head. It's definitely metallic/mechanical--and it's pretty loud. I'll change my oil and have a look. How big are these pieces of metal that you're talking about?

 

They would be shavings, not big peices. Unless you're in serious crap...

 

to give you a little more sure that it is in the block if you unplug the sparkplug wires one at a time if one of the cylinders are bad that noise should stop.make sure you take only one out at a time and watch out for the spark.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drowzysleeper &raquo;</TD></TR><TR><TD CLASS="quote">to give you a little more sure that it is in the block if you unplug the sparkplug wires one at a time if one of the cylinders are bad that noise should stop.make sure you take only one out at a time and watch out for the spark.</TD></TR></TABLE>

Can you elaborate on this a bit more... I don't think I understand what you're saying. TIA

 

OK, here's a little update: (EDIT-- I noted the rocker arm wiggling BEFORE adjusting the valve clearances )

1. Checked valve clearances. They were slightly out of spec, and I adjusted all of them.

2. Dropped oil pan. There was no metal shavings in the bottom of it, or in my oil (that I could tell).

3. Did a compression check. Results (cyl. 4-3-2-1): 170 180 175 180

4. Had a closer look at the head... noticed that the rocker arms (the fixtures that hold the adjusting screw/locknut) were loose on several of the valves!!! The had some play in them, and I was jiggling several of them around. Is this normal? Not all of them were loose like this... perhaps 7 or eight of them (some on intake side others on exhaust side). What can I do about this?

5. The noise has not gone away, and is not getting better. Help! I'm going to a dealer tomorrow to get further diagnosis. What do you guys think I can do?


Modified by mdpalmer at 9:31 PM 3/26/2005

 

TTT

 

Easter bump

 

Update:

I had the dealer take a look at it (diagnostic fee = $80 (!)). They determined that the noise is definitely coming from the head, and that there is no way to tell what the problem is unless the head is removed (****!). Then they can check the rest of the valvetrain for any damage or problems. So remachining of the head, plus replacement valvetrain components (assuming that only some of the parts took a ****) was quoted at about $1200. God dammit! I'm probably going to just pick up another engine and drop it in. I can get away with that for about $2000 I think. What do you guys think about this? Do you think I should have the head removed and checked out, or just get another engine (assuming I can get one in decent shape)? TIA



Modified by mdpalmer at 5:59 AM 3/29/2005

 

Are you positive its not the gasket form the head to exhaust ticking and making noise ? I just went to war over my buddys car with same issue and he pulled it and sure enough...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PK SPEED &raquo;</TD></TR><TR><TD CLASS="quote">Are you positive its not the gasket form the head to exhaust ticking and making noise ? I just went to war over my buddys car with same issue and he pulled it and sure enough...</TD></TR></TABLE>

Yeah, I triple checked for exhaust leaks... I was hoping it was something little/simple like that. Trust me, this noise is a super loud when you're on the throttle. the techs at the dealer were like WTF when I drove in. So I wouldn't call it a tick, I would like to think of it as a rattling/chattering/knocking noise

 

my car would make the rattle sound, only when revved up it would ratle at peak of the rev, and constant if driving under load...turned out a rod bearing wore down, and after a day of troubleshooting, it got SUPERLOUD, the piston was tapping the head, i have the word IN on my head now! so i completely rebuilt a shortblock and noted all clearances, made SURE i had it all within spec...now it's perfect

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by darrinbrewer &raquo;</TD></TR><TR><TD CLASS="quote">my car would make the rattle sound, only when revved up it would ratle at peak of the rev, and constant if driving under load...turned out a rod bearing wore down, and after a day of troubleshooting, it got SUPERLOUD, the piston was tapping the head, i have the word IN on my head now! so i completely rebuilt a shortblock and noted all clearances, made SURE i had it all within spec...now it's perfect</TD></TR></TABLE>

Heh, you had "IN" stamped into your head... I wonder if I have the same problem. My question to you is: how much did you spend to have this thing done? I'm assuming that you probably did the work yourself (props to you if you did)...

 

well, i bought a perfect crank ($100) bearings(180) block honing and deck checked ($100) , misc seals, new oil pump,eagle rods and cp pistons(.020 over). my actual bearing broke the tabs and spun, ruining the crank AND rod.. since i was in that deep, i did the rods and pistons, changed syncros in tranny, new clutch and flywheel. speedworks (HT member) did my work. just completed this weekend.

the sounds started high, like the head or maybe a loose wrist pin, the "engine ear" thing we used even sounded like it was high in the engine..was a bad bearing the whole time..

 

sorry i didnt post back sooner what i meant by doing the spark plug wire thing was:
1 start your car
2 pull off the spark plug wire on the first cylinder and see if the noise stops, then plug that wire back in.
3 repeat #2 for the rest of cylinders, if you find that the sound stops, you prolly got something wrong in that cylinder.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drowzysleeper &raquo;</TD></TR><TR><TD CLASS="quote">sorry i didnt post back sooner what i meant by doing the spark plug wire thing was:
1 start your car
2 pull off the spark plug wire on the first cylinder and see if the noise stops, then plug that wire back in.
3 repeat #2 for the rest of cylinders, if you find that the sound stops, you prolly got something wrong in that cylinder.
</TD></TR></TABLE>

Oh, OK I tried it... and the noise was present no matter what plugs were pulled. Thanks man.