Engine: Blue top F20B Dohc Vtec
Mileage: Roughly 120k

Getting almost like a rattle/tapping noise coming from the cylinder head. More noticeable at cold start ups. When fully warm the noise does calm down, but its still there. The engine has full compression. Auto tensioner was replaced not to long ago when i replaced the timing belt(apparently that causes common engine noise). Reving engine between 3-4k rpms when cold, really makes the noise apparent. As i said engine has full compression, and doesn't appear to have performance loss. Some research ive done ive come across lma's for fairly common cylinder head noise on vtec motors due to the rocker kind of flinging around. Though im not sure what type of lma's this motor has. It's a obd2 motor, so i assume it has the updated lma's but that's assuming, and do the updated lma's commonly go up as well. Any advice is much appreciated, i know its not a extremely common motor.

 

have your adjusted your valve lash?

 

Yes, my apologies for not including that.

 

I have the same noise with mine. At start up also, until it gets warm then the noise disappears completely. The tensioner was changed very recently so I know that is not the culprit. I am thinking it may be in the valve train area.

I have an H22A head that will be getting all new valve train, ported and polished soon. When I do the change over I will investigate the valve train thoroughly to see if I can find the source of the noise.

 

man i thought i was the only one with this problem. granted im running mine in my 94 accord but before i did the f20b swap i had swapped an obd2 sohc f22 vetec into it so with that came a whole wiring harness swap cause i didnt have a ecu conversion harness. so im also using the stock ecu from the f22 vtec, now it runs like a raped ape but i have that same noise and it sounds like a diesel at times, but its noisy as hell on cold start ups but only calms down a bit not completely gone when warm, so i was wondering cause the ecu im using kicks vtec from 2300 on up to 6500 where the rev limiter is, would thhat be the issue?. and i really wanna wake it up at some point to allow it to rev out to its full potential but not sure on what ecu i should use considering i have an obd2 system, but i dont have to worry about it much cause its in an obd1 car so they dont hook up a scanner. and info greatly appreciated. thanks dan

 

VTEC from 2300 to 6500? hahaha thats great

 

yeah im using the stock f22 ecu, which is sohc and also had the low vtec start point, not makin it up, just not sure if its added stress or what.

 

I am going to agree with him ^^ what octane fuel are you using BTW?

 

had no choice really my other engine had a broken casing where the front mount went so i needed an engine and all the f22's i found were more than the f20b i found from jdmenginezone.com, and havent found a good "this is the ecu you need" answer so i cant really be bashed for my lack of funds and resources. and i bought the supposed correct ecu for the engine plus the obd2Ato obd2B conversion harness, and i hook it all up and it doesnt run right at all almost like its got a massive intake leak. which it doesnt. i run mid grade octane. yeah believe me i feel sorry for it too cause its such a tease when it hits its powerband around 5000 and then i have to shift at 6500, when im on it. im only looking for help not to be ridiculed so please in advance save the harsh comments.

 

:facepalm:

Wrong ecu for the engine and going wot and wondering "whats that noise?" Idk, floor it again and lets see?

... people people.

 

it is very widespread problem on f20b dohc. i think it is wear of camshafts beds. i have seen only one engine without that noise among many ones with it. forget it, it is annoying but harmless.
i mean noise like this http://www.youtube.com/watch?v=a0EKcP7fO7w

 

why not d15b ecu?
it is cheaper but correct to the same degree

 

wow...this is what happens when i don't check my post in 3 days.

I personaly ran this engine with a p13 to start. But i now have a chipped ecu with a stock f20b basemap.

Noise im getting though you would think would be more apparent in the higher rpms if it was a lean issue. Still kind of leaning more towards the LMA's(lost motion assem) due to the fact that the noise is outside of vtec in the cyl head. Outside of vtec the rocker arm should be flinging around if the lmas are not working correctly.

 

yeah see its exactly like the vid on here, and the noise goes away completely in higher rpms, i also forgot to mention that both my o2 sensors are junk so i would imagine its dumpin fuel which would be better than lean.so idk.i want to find an ecu that isnt on ebay. and is from somewhere reputable but also isnt 500dollars.

 

That sounded like a Pinging/Spark Knock issue. Thats what pinging do is rattle the valvetrain area which will cause that noises.

 

Sigh...now this makes sense too. When the temp is cooler the more air the engine is getting, so if the engine is getting more air and its running lean, thats obviously a no no. Wondering if the p13 will make it run richer until i can get the car to the tuner. Though does the computer over compensate that much agressive fuel dump during vtec that the noise goes away at higher rpms?

 

Lean= excessive oxygen.
Rich = lack oxygen.

You're right! But other factors can cause the motor to lean out.

Things that can cause it to do so are:

-A/F ratio too lean
-High Compression
-Coolant over protected
-Ignition Too Advance(It might be the other way for this one)
-EGR valve stuck(close or open, I forgot)

There's alot more to it but these are the ones I can remember off the top of my head. I learned this in Auto Tech class, so yup.

I think you'll do fine with the P13 til you get your car tuned with a chipped ECU. Just don't beat it to ****, you know?

 

believe it or not no no real choice at the time, i was more worried about the head noise, and no i dont rip on the engine all the time granted when i got it in after about 800 miles i ripped it once or twice i mean be honest who wouldnt. now ive seen this coming knowing i had the wrong ecu in but eh whatever, but the other day i was cruisin down the highway doin 60 on my way home from work and my car just stalled on me so i pulled over tried starting and oil light was flashin so naturally i went to check oil, but dipstick was blown out and oil all over the place. turns out after rippin the head off i burnt 1 and 3 pistons. i know that it wasnt smart runnin it with the wrong ecu but i also wasnt beating it throught the time it was in the car i put 3000 on it with that ecu. so i found some things out while i had the head ripped off. i had the old 2.2 sohc vtec block layin around and measured the bore with a caliper and then measured the f20b bore, and the pistons from both too turns out theyre exactly the same which is weird cause the f20 is considered to be a 2.0 so how do the 2.2 l pistons fit. but on another note i am going to be fully building this engine and i will be taking down plenty of specs on the internals seeing as there is almost no records of them. ive started working at my uncles trans shop so im making alot more money finally. so i will be building this engine correctly not to mention getting either a p13 or p28 and the hondata system and converting it to obd1 to make things a bit simpler. but for the time being i found new sources for engines at cost now that i work at my uncles so i will be picking up a standard 2.2 sohc vtec for now so i have something to drive. for those who did help give usefull info to me and didnt give me crap i thank you and if anyone cares i will post up on my build.

 

I was just going to say sounds like broke ring gland . I have had 8 f20bs and put tons of miles on them thats a very well built engine with no noise issues . My fully built h22 sounds like a damn diesel but i know its the lmas sticking been like that for two years . f20bs run the newer spring lmas and normaly dont have that problem actualy untill this thread i have never seen anybody have problems witht these engines i mean there such a well built engine tear one down you will see what i mean . I have personaly beat on one of these for three years reving to 9500 ( I was to young to no better back then thought it was cool) with no issues . I have torn apart a tone of h22s with broke ring glands that ran good ,compression checked fine ,might have smoked a tad,but sounded like **** running . I hope you get it figured out man good luck they realy are a hell of a motor especialy for the price. Also the five speed f20b comes with type s cams so dont go swapping **** out and get rid of them there realy nice cams .

 

f22 gets its displacment from the crank .If you run the part number on f22 crank and rods its they same crank out of a h23 so a f22 actualy has more stroke then a h22 and smaller pistons which brings it back to a f22. Ill have to check tomorrow at the shop but f22 are supposed to have 95mm pistons and f20b are supposed to have 86mm pistons if i remember correctly but i could be wrong . I have both laying around so i will check . A f20b is nothing but a h22 d stroked in order for honda to run in the 2.0 class in racing . The five speed come with type s cams and springs and a 66mm throttle body even the rods are beafy realy a nice motor. Also they have factory steal sleeves and 55mm mains . Its a great block to do a g23 build with out doing the bull **** to the f23 block just i idea for a easy build . i personaly have 15 h22 and 3 f20 b heads at the shop and have been doing this for along time ive never seen cam journal wear . I have seen low oil pressure cause cams to seize but not wear and still run making noise. Also the f20b head has 1mm smaller valves something they did because it being a 2.0 liter so i didnt need as much air and also helped it rev higher (just what honda said lol). Other then that and the newer style lmas same head . I have read that f20b head has smaller combustion chambers this is not true and the f20b head flows better and is port and polished form the factory this is not true either its based off the same casting as a h22 head only the valves are different hope i helped.

 

I appreciate all the info, sorry its been so long since ive gotten back to this forum. I actually still have the noise after getting a properly tuned ecu, so its no the original thought of being lean or to rich. Compression is still holding strong, and oil consumption is typical for a prelude. So who knows...i still think lma's. But i dunno

 

yeah it is annoying