engine noise

[terra]

okay, I'm a newbie, but what a wonderful site...now for a couple of questions...90Honda, stragiht, F/I, 185K miles...whenever it starts, it has this tapping noise...does not matter if its sat for a day or two weeks...I assume its metal against metal, all the oil has drained down, etc I have often wondered if I put a small amount of oil in before starting it, if that would help...half a cup or so...no, not a on a daily basis, but after its been sitting for a week or so...mechanic says.."well you have alot of miles on this engine..what do you expect?" the noise goes away after it warms up...

I use 10/30 castrol, and change it every 3000 miles...would a different vicosity help this?

Also when cold, when starting, it used to rev up, and then slow down, inside of few sec...Now it revs up and seems to take like 5 min to slow down to idling speed..is there something that should be replaced to prevent this???

no one seems to know what I'm talking about..do you folks have any ideas? or should I just count my blessings the lil baby still runs.....

 

[paulinfiji]

Hello Terra. It might be your oxygen sensor that needs to be replaced. My father's 1994 Acura Integra (205000 KM/128125 miles) had a problem with rev fluctuation after start-up and it continued for 3 to 5 minutes before idling normally again. After he got the sensor replaced, it idled normal after start-up. The tapping noise in your engine is normal due to its age. It happened to my 1988 Accord, which is now in the junk yard. Don't overfill your oil above the top dot of the oil dipstick. You can try using a thicker oil like 10/40 or maybe half 10/30 and half 20/50. Hope this helps.

 

[terra]

thx folks, I'm gonna try it all, starting with the oxygen sensor...and am gonig to try a thicker oil, and see if that helps...car doesn't get driven every day, just one question...

Quest....what in the world are valve lashes?????

 

[terra]

may of let you folks astray there on the Honda questions....as I'm not too good of a DIY...I have the book on the thing, but am wondering if this is something I can do myself, I had changed the PVC valve, but that was right in plain site, fellow showed me where it was...but if replacing oxygen sensor/coolant sensor, is very technical, maybe its best I take it to mechanic, and say "replace this and this and this" always trying to save buck here and there, butodn't want to screw anything up, ya know?

 

[Quest]

pistonslap is a norm on some older Honda engine designs.

Assuming that the engine is original (never been rebuilt or "touched") then I would just say go easy on it while warming up the engine and you'll be fine.

Make sure you adjust your valve lashes also.

As for the revving up part, check your thermostat (might as well replace it given it's age) and also coolant sensor.

 

[paulinfiji]

Hello Terra. I'm not a mechanic and I have never replaced an oxygen sensor but I can tell you where it is. Behind your engine and on top of the intake manifold (four tubes) is the throttle body. Attached to the throttle body is the black plastic intake tube. The oxygen sensor is the small metallic device on top of the throttle body. I don't believe it is difficult to replace because it is reasonably accessable, but I can be wrong. Do a search on the internet of how to replace an OS. It only cost my dad $50 to replace it by his mechanic. Sorry I cannot be of any good help. Good luck.

 

[terra]

thx paulinfiji, its so hot here, I haven't even looked under the hood, I just want to hide in the a/c.... but did look in the book, I might be able to find it, with your helpful hint...also looked up the price on the internet...about knocked my socks off, one place was like $170....but I think it was Bosch that was like $63...thanks much....

 

[charbaby]

Check the valve lash and adjust the valve if needed. Get a hold of a cheap service manual(Haynes or Chilton) for the specs and procedure. I have never known Honda engines to have piston slap. These engines have solid lifters,(not hydrolic) and need periodic adjustments.

 

[terra]

Char Baby...thx....I do have the worthless Chilton Manual...and car needs a oil change anyhow, so gonna have mechanic to point out the oxygen sensor, even tho I do think I have found it...and ask about adjusting the valves...

I am trying for 300k on this car, so maybe taking care of these seemingly minor things now will acheive that...that's my objective...

I am so impressed with everybody's help, hints etc...this is a wonderful site...

THANK YOU MUCH...

 

[TxGreaseMonkey]

Get valves adjusted and use 5w30 synthetic. Synthetics build oil pressure much faster than dino. Valves are last on the oil train and the first to go.

 

[Tosh]

I thought O2 sensors sat in the exhaust.
Throwing parts at a problem can get expensive without curing anything. If a valve adjustment doesn't help the tapping noise, you could make yourself a stethoscope and listen for where the noise is coming from. You need to find an independent mechanic who specializes in Honda. Maybe the MechanX Files on CarTalk.com would turn up one. I had a good one who would tell me what was wrong before I even finished describing the problem over the phone. And he would encourage me to fix it myself, because he was so busy.

 

[TxGreaseMonkey]

They do.

 

[paulinfiji]

TERRA. Tosh is absolutely correct. THE OS is located at the bottom of the exhaust manifold. I think my dad's mechanic had that confused with the sensor that is on top of the throttle body. I'm truely sorry. However, my dad said that his mechanic changed the sensor that was on top of the throttle body. I don't know if he changed the OS though.

 

[terra]

to all of ya....thx again...Because of being busy, I was unable to talk to my main mechanic, who I trust with my life....so I stopped in a few auto stores...and what I thought was a oxygen sensor, nope that wasn't it....but I have no intentions messing with this, until Iknow exactly what is going on, the where, the why, etc etc...I personally feel the OS should be replaced, and the valves adjusted, just because of all the miles on the car...I don't feel that would hurt anaything....and the car runs fine,except for the rev at startvup, and the mickey mouse noise, till it warms up, but was thinking maybe a lil preventive maintenace today, might save me the big bucks down the road...I found TxGreaseMonkey comment
very intereting about valves, caue that's something I surely didn't know...all input is appreciated,

 

[mechtech]

The O2 sensor DOES NOT have an effect when the engine is cold! It is not used , then.

Try cleaning out your throttle body/bore, and check you idle air valve. Vacuum leaks are another probable cause.

 

[terra]

thx...Yes, vacuumleaks could definitly be the cause...15 year old hoses..very possible...

 

[Jim Spahr]

One cause of engine noise at start up is the oil filter ADBV-anti-drain back valve. It is supposed to keep oil in the filter to prevent a dry start up. So I would check the oil filter that is presently on the car and get a Honda filter from the dealer. Then fill 1/3 full of oil and install on the car. Some after market oil filters don't have the correct ADBV. Changing types and wts of oil may also help. Do a search in Oil section and filter section and read those posts by Honda owners.

 

[Jim Spahr]

Here is an internet site for engine noise at cold start. If you visit, I think you will see many makes of cars listed here such as Ford, GM, and Honda. http://www.pistonslap.com/

 

[terra]

thx...Pistonslap is one hellova good site..learned much....and will try the HOnda filter see if it helps plus different weight of oil...thx again...