hey everyone, im a new s2k owner, its an ap2, i bought it highly modified, and already have a problem...the first problem is this strange vibration noise and feeling in the engine, it doesnt do it at idle, but only in the rpm range 2200 to 3000rpms, when i touch the engine it feels like its the top end but not sure, ive looked at other posts trying to figure it out but am having trouble understanding since the vibration is only in that specific range. The engine runs perfectly and im running farely high boost (about 17 psi in a garret gt30), it didnt do it when i bought it, and if it did i didnt notice it at the time, i know enough about engines to repair it, just away from home without tools, if anyone could help me troubleshoot this problem i would really appreciate it please help!!!!

 

I had the same thing gong on with my boosted AP2. It just started out of the blue. Ended up cracking my manifold. I tried aftermarket motor mounts,injectors cleaned,tune looked at, belt, turbo rebuilt, tans mount, spark plugs, valve adjustment, gas cleaner, head gasket, new pulleys, new act pressure plate , new clutch, new throw out bearing, checked every bolt, changed oil/trans/ diff fluid... NOTHING HELPED!!

I started to get what seamed to be a misfire a few weeks later but I didn't get a code and no check lights on. Hondata flashpro data log didn't show anything. I changed the plugs again and regaped them to 18 (E85 - 15psi) and i still had both problems. I pulled the head back off and dropped it off to be check out. I had 2 bad valves, so I had the whole head rebuilt with all new parts. I ended up pulling the bottom end and took it apart. It all looked good. I ended up selling the head and Im now dropping a new long block in. I'm not sure if it was the 2 valves that were giving me all the crap and ill never know. I didnt want to put it all back together and the vibration still be there.

I know this does not help you at all ... BUT.. You know now what you don't need to do. I would start will pulling the head and have the valves looked at. I'm guessing the 2 valves were it.

I ended up parting out my whole turbo it and about to just run N/A with a new motor. I NEVER WANT TO RUN INTO THAT AGAIN!!

FYI--- keep a look out for it to also start around 4000 rpm's also. Mine would do it around 2200 rpm's, went away by 3000 rpm's... a few weeks later I had 2 different points...,do it around 2200 rpm's, went away by 3000 rpm's came back around 3500 went away around 4000.

not going to lie.... after doing all that work to try and fix it and nothing helped... I sat and cried.. Then I just bought a new motor, I should have it in this week.

 

nice man, that actually help quite a bit. I originally thought about the valvetrain, so i took the VC off and started looking for loose adjustments, )i used to have a 4th gen prelude si so i know all about loud ass heads lol), but i didnt really find too much some stuff the felt too loose, i thought maybe bearings or weak or loose valve springs, or something, now im just wondering how much its gonna cost for labor to get new valves, seals, springs, and retainers put in, i was really hopeing to not have to take the head off, but now i guess im screwed, what was wrong with your valves when they were claimed to be bad???

 

2 exhaust valves would not seat all the way. There is no way to tell if its the head unless you take it off and take it in somewhere. Go to hondatpartscheap.com and buy the parts you need that way a shop wont over charge you for them.

 

sweet thanks alot man

 

Cracked retainer or valve adjustment?

 

Cracked retainers show 0 symptoms.

Do you have innovative motor mounts?

 

hey sorry guys been gone for awhile....anyways vibration still there now its just at 3k rpms and found out some of the exhaust was making the vibration louder so i fixed all of that, problem is the vibration is still there it just doesnt make any abnormal noises now, strange i know, one thing i noticed is the blow by, and some mechanic told me the vibration is piston slap, hmm weird cause im sure i would here a knock, and like i said this thing hauls, so i dont think im loosing compression, i need some help getting the pressure out of the vc but thats a different topic, i just want to know what the vibration is because its cracking my sidewinder manifold... could it be TCT and guides???? its only got 31k miles

 

I know this is old but I too have a bad vibration at 2300-2600 then 3k ish. It a very harsh vibration. Car makes plenty of power and runs smoothly otherwise. I'm sure we all have different problems. It cracked my manifold as well. Hope some people who fixed this issue can chime in with what fixed it. I think it's mostly the exhaust resonance