HELP!!!! I think... Just this past few days I began to notice a slight knocking sound coming from the engine mainly when shifting from 1st to second or when decelerating. I can reproduce the sound easily by putting the engine in park, revving the engine gently to about 2000 rpm then let off the gas, and grr,.. a little knocking. I've read in a different place that this could be a number of things. One thing that caught my ear was a possibly bad tensioner for the timing belt? This was changed last summer with the timing belt and balancer belt. Could this be the cause or something else? If it is, is there an easy way to check this without pulling the wheel, removing the mount, removing the covers and looking at it directly? I want to nip this in the bud before it gets worse or causes other problems. Any help would be great! Thanks


HERES THE YOUTUBE VIDEO

http://www.youtube.com/watch?v=Kj2thVW2odo

 

When there's an issue with the timing belt you generally end up with engine codes. A few degree's off on the timing and you get knocking and pinging which will set a code; O2 output becomes too rich which sets a code, or you get backfiring through the air intake or exhaust which you'll hear and definitely sets a code.

Your problem actually does sound a lot like Backfiring; backfiring makes a catalytic converter glow due to too much fuel being burned up and you'll hear it at the rear of the car.

Knocking like that can come from anything and anywhere; accessories, belts, loose valvetrain, electrical shorting, etc.

Grab a 2 foot screwdriver and go from accessory to accessory and listen in (butt of screwdriver to your ear). See if anything is making bad sounds.

If that isn't it, rev the engine in park to 2000 RPM and hold it for 1-2 minutes to see if any codes get set; O2 sensor won't set a code if you get a little water in the gas but it will set a code if there's a consistent problem.

Listen in on the valve train, if you've never loosened and re tensioned your rocker arms bolts they can be the culperate of bad timing at higher RPM's.

Check your ignition system for proper timing, pressure test your cylinders.

Once you're sure it isn't coming from outside of the engine block, then the best you can do is try different points with the screwdriver or a stethoscope on the block to see where in the block it is coming from. But to be honest at that point, 9/10 times, the block is toast.

Word of the wise; get a quality remanned block with a 3 year warranty minimum. You can disassemble, take parts to a machine shop, order custom parts, and build your own block but in all honesty, a shortblock will make your life easy.

 

I would do a couple things before ordering that short block.

1. Remove the accessory belts, then start it up and see if it knocks. This will let you know if you have a pulley locked up , or a bad bearing or pump. If the knock goes away start checking pulleys. If the knock didn't go away go to step two.

2. Remove the timing cover and check the timing marks. Inspect the belt and check tension. Then Remove the balancer shaft belt. Start it up, if the knocking goes away then you know one of the balancer shafts went bad. You can run an engine without the balancer shaft belt. If the knocking didn't go away, buy a short block.

 

Thanks guys for the information. I have looked through the posts and today did some work on the engine related to a different post of mine. I was getting a few codes, 1457 and 0401, evap valve and EGR. I removed the Plenum and cleaned it well. There was a crap load of gunk packed in the EGR port of the plenum. I reset the compute to clear the codes. I let the thing run on the current tank of gas that was very low. It ran great after cleaning the plenum. I didn't check for knocking yet, but, my mother, who used to do mechanics, gave my an idea that the gas may be bad. HOLY CRAP! Why didn't I think of that??? So, I filler er up and no Knock, other than the normal "Knock" sound that comes from these engines. I drove the car all over creation today and not only did it run perfectly, but no codes have shown up yet! The evap valve test apparently takes forever and a day to complete now. Before cleaning everything, the engine light would be on within 20 miles. Today, I drove far more and still nada. We shall see. So, the knocking is gone, prob bad gas, and the codes have not come back yet from cleaning the plenum! Awesome! BTW, HON2984, is your build done yet? I checked out your posting and it seems like you're having a heck of a time. I look forward to seeing the outcome!

 

No not yet. I'm almost ready but it will take some time. I have all but 2 items. When I went to have it tune we found another problem. Either my fuel pump is maxed out at 38 psi or I have a bad FPR. I already have a Walbro 255. I've already ordered a new AEM AFPR, but I havent got it in the mail yet. It doesnt come with a gauge or a port for a gauge, so I'm getting a B&M gauge which I have not ordered yet. Once I get it I can start on the fuel system. Once I get It done I can start the Head Swap again.


I hope that takes care of your problem. What model,year,motor ? 96-?

 

So far the car is doing great! I can't believe the difference. Still waiting on the code since the last compute reset yesterday.

The car is a 99 accord. I have the ULEV V-Tech 4 cyl. I've installed and AEM intake and am master debating if I'll install my old Jet V-Force control module. I'm still collecting info. I don't want to install anything that'll make matters worse yomesay? One day I'll post some more about the vehicle in my profile area. I want to get a little more done with it first to make it sound better yomesay? Oh, BTW, yomesay is short for "Do you know what I'm saying?", or, "You follow me?", or, "Your mom called!". Yomesay?

Ok, enough randomness. I was up late and need more sleep.

 

the knocking is back at the same rpm. ill try the earlier suggestions. i just checked my valves today. i adjusted the to .25 on all. i hope i did i right. the car ran great until a little while ago. if i rev the engine to 2000 the let the gas off slightly then press a little more back to 2000 the is a very noticable gergling knock. the heck. it was perfect for a while other than a slight ticking while speeding up on the highway. man. i dont know. bad gas?

Any Ideas? It's from 1500 - 2300 rpm. It's driving me nuts. Somewhere said amsoil engine flush.. There was some bonehead on youtube revving the crap out of his engine and the same sound was present. A few comments mentioned amsoil engine flush. Should I do a youtube vid and post it?

 

Ok, did the youtube thing, here is the video

http://www.youtube.com/watch?v=Kj2thVW2odo

PLEASE let me know what this iS!!!!

I have to add that when driving the car it sounds smooth as silk and shifts smooth. It does feel like it's held back at ties but I guess that's common on these cars.

Is it possible this is the cause???

 

HELP! BTW, I've changed my oil to Castrol Syntec 5w 30 synthetic oil. Still, this knocking persists. I am so discouraged! Holy crap. Not to mention the pulley!!! NAPA what the heck.

 

Vtec?

 

Yes, it's a vtec as you can see in the vid. Is the video not working?

 

It sounds like teeth from a rubber belt scraping on plastic from the video.

I wonder if you timing belt cover is jacked and rubbing on something?

 

The timing belt was installed less than a year ago. When I did the valves this past weekend there was nothing visually wrong with the Timing belt. If standing on the drivers side and looking at the cam pulley at the top, the left hand side of the belt has a very slight slack in it while the right side is tight. I installed this belt along with the water pump, tensioner and balancer belt. I made perfectly sure I set everything as suggested and that everything was dead nuts TDC. Plus, the plastic covers are in good condition and there is no unusual wear on the belt. Interesting thought though. I'll have to at least pull the bottom cover off now and look at everthing again.

As an update, I took the car to the Honda dealer today. One of the Techs came out to the car with me and sat in it while he listened to the engine while I revved it to 2000, down to 1600 then back up to 2000 to demonstrate the issue. He said it does not sound like a rod knock at all! GREAT NEWS!!! He did say it could be piston slap. Now, piston slap, where it seems horrible to think that your piston is "Slapping" anything, apparently that is not harming my engine! That's also good news. The tech suggested Techron fuel system cleaner (??? fuel system cleaner for piston slap?) and the guy at Levine suggested that and Lucas oil, for me the synthetic stuff since I'm now running synthetic. This may help. In a way I'm happy about the news but this is a nagging sound and I want it gone.

Like I said, I did my valves this past weekend and checked them 3 times I set the intake to .26mm and the exhaust to .30mm. I may check them again to be completely sure everything is perfect.

Lastly, what I'm checking and replacing today is the knock sensor. This is used to help the computer determine if there is a knock and either throw a code if it's a bad knock or adjust the timing to limit the knock if it's timing related. From what I understand, if this sensor is faulty the car may knock. Correct?

I'll change my knock sensor tonight and add the Techron stuff to a half tank and go from there.

What do ya think?