maŽEX

HELP! 92 JDM FD3S Strange noise from intake air filter at iddle! (NOT "MOO" SOUND)

Hey everyone, new to this forum but not new to cars and etc, had this baby over a year now and here's the storey.

Car had perfect compression, 12k miles since last rebuild, new spark plugs ~300KM old, all new hoses in rats nest and around were replaced with high temp silicone hoses, new high capacity radiator including all new water hoses, all new viton check valves etc etc, new oil at the upper dip stick level... Im just running out of ideas.

So 4 days ago I started her for the first time after 5 months dry storage (while was sorting out all the solenoids that were broken and redoing complete hose system by the diagram, also sorted leaking pan with new gasket+high temp rtv silicone+ss 5mm oil pan brace and stud kit, everything is nice and steady at that point)

it was past 10pm that evening and I did not realized I forgot to bolt on the exhaust pipe to downpipe so I was really forced to cut engine off ~3minutes later, I know bad decision but neighbourhood rules. So I did realized I most likely flooded the engine, and wasn't expecting her to start another day at all but she started fine, and about 1more minute later this grasp sound from intake manifold has began to occur, it would sound like something is not right either with some of the vacuums or throttle bodies I dont know now... it has went away that second day for about the minute and then came back and now this is like that for good.

I've cleaned all the spark plug wires prior putting them all back on, I have decided to take all spark plugs out for the day cleaned them and inspected all seem OK, that didn't help, so I thought maybe I have air pockets in the system somewhere like where the hose bypasses the thermo-valve of some kind near the throttle body, and I did very long taking procedure de-airing the system now its completely free of air but I still need to test start her today and see if that made any difference...

one friend suggested it could be turbos or motor going, but the weird thing is if I flick the throttle cable this weird idle noise will go away for that time and will come back when cable is released and motor rpm back to idle state.

FYI my airpump has been removed and necessary pipes blocked off, my AC is removed too and so is the AC rad with the electrical solenoid.

I have uploaded 1080p FULL HD videos to youtube maybe you can check it out and give me your blessing what I may have done wrong or what to do to sort this out?

Youtube Videos:







Things I have to try today are:

1. while motor is running remove spark plug leads one by one see if there comes the spark - May it be LEADS / COIL's / or eves spark plug's? (FIY I run original spark plug setup with leading and trailing correctly positioned)
2. Will want to measure TPS for voltages
3. Also my ECU harness had some hand made jump wire (or 2 wires) installed right before the plugs to the ECU, I will take a pic of them and maybe you would know what that can be all about? As for now its running stock ECU, I have Apexi PFC but its mapped by someone for non-sequential turbo setup, I need to reinstall fcedit and load baseman I suppose before I can hook this thing up to my car.
4. I will take off the IM pipe and check the butterflies for any obstruction or damage etc. Weird thing is that the car would idle smoothly before I took redone all rats nest, but would jump a little bit randomly at low rpm due to solenoid tips broken and poor vacuum hoses

I've forgot to mention - when car warms up a little @ ~80c she behaves just like its shown in the last shortest video above, so I take its something to do with throttle bodies or vacuum system? this video must be watched what happens if I kept on moving the throttle cable sound just disappears while motor revs up and down.

Fd3BOOST

That's weird, sounds like some sort of vacuum leak to me but obviously the idle is decent so might not be your problem. Did you try taking the air filters off and checking them? I'd check them plus the elbow etc... It's got to be something really minor. I don't think that is anything with your motor or turbos.

maŽEX

Update:

I was advised by some experienced rotary minded fellows that it may be my one of the CAS, either dirty, rusty, damaged, broken wire between CAS connector to ECU or loose plug to CAS! So it was, my GRAY CAS plug wasn't fully on and it actually took me 20 minutes to push it back on, it was that hard. It just would not move extra 2mm needed due to old expanded rubber seal, however I made it happen its there now, also cleaned them and cleaned the metering disc and pulleys... I have not tempted to start the car because I have previously messed up with idle control and it will take some time to get it right if its off by much now, and it is actually past 11PM in the neighbourhood so Im taking no chances against neighbours patience

Im gonna start it after ~10hrs from now, I will be back from work and should be good to go.

Can anyone advice me how to set the lower air bleed screw under the intake manifold? I have read somewhere as If I tighten it closed and unwind one round I should be ok? or is that some nonsense?

maŽEX

sorted now, thanks

maŽEX

sorted now thanks