Possible Vcis/Vtcs issue?

[whatusername]

hey guys i finished rebuilding my enine n the cars runs pretty good (i was really surprised at the handling) but when i rev it just above idle i hear a noise in the head that scares me its a deep rattle. I searched the web n saw a tsb on the vtcs or vcis i cant remember n it showed some customers will experience a rattling noise from head when temp is below 65 deg Celsius. Anybody else experience this? i saw a thread on the vcis/vcts but the links in it are dead.. seems alot of links on here are dead. if those things are at fault i would like to know how to remove them to do a delete. i know there is a How-To thread on that but like i said the links in it showing the how to are dead. Thanks to anyone that replies

 

[BRIAN_MP5T]

Those features aid in Cold Start and Emissions. If you disable them you may end up with issues depending on what the laws are near you.

Removing them is really simple, you can drill out the screws and pull the flaps out, then remove the rod.

You will have to tap the rod hole to a bolt size and bolt up the hole (to seal it)

As far as the inner flaps, you need to unbolt the two halves and do the same thing as the runner flaps.

You might loose some bottom end torque, however it is no negligible that you might actually feel the car is more powerful due to the reduced resistance.

 

[whatusername]

Those features aid in Cold Start and Emissions. If you disable them you may end up with issues depending on what the laws are near you.

Removing them is really simple, you can drill out the screws and pull the flaps out, then remove the rod.

You will have to tap the rod hole to a bolt size and bolt up the hole (to seal it)

As far as the inner flaps, you need to unbolt the two halves and do the same thing as the runner flaps.

You might loose some bottom end torque, however it is no negligible that you might actually feel the car is more powerful due to the reduced resistance.

lucky for mr there are no emissions over here and since im in Florida cold is really not much of an issue,I just want this damn car to stop sounding like there is a marble in the head. so that pic is of the intake with the VTCS removed? what is the Vcis? do i need it?

 

[BRIAN_MP5T]

 

[whatusername]

thanks brian but can anyone tell me if the marble in the head sound is the sound that the vcts makes?

 

[ScratchNSniff]

It is...

 

[whatusername]

Thanks Scratch

 

[P-Funk!]

For me - it is the VICS shaft 'play' from being worn that would rattle. I had red loctite'd the screws. I had also removed VTCS butterflies...

So it may rattle and not be a problem.

 

[Installshield 2]

VTCS is a known cause of the rattle, but we haven't heard your engine...so you're sure everything else was assembled properly?

VICS and VTCS are very different though...VICS has no known problems with a naturally aspirated FS engine...many turbo guys remove it, as it could be deemed restrictive in forced induction systems...but you'll gain absolutely nothing from removing it on an NA FS, and will lose some low end torque...its not a huge deal though, many guys swapped to a 626 IM on an NA protege and didn't care (the 626's of certain years didn't have either system in place iirc)...VICS changes the runner size depending on engine speed and load, and effects the speed and amount of air that gets to the engine in different situations...its not really an emissions system, its just Mazda's alternative to variable heads...or at least, it used to be...

VTCS can be removed, though...but it takes some messing around, and there are multiple ways to do it...just pointing that out...some ways will throw a code (if you pull it out and just disconnect/tuck the connectors) with the stock ecu, though...

Brian put down what needs to be done...the hardest part by far is just getting the IM off...If you're set on using your stock ecu, you'll have to leave the actuator and vacuum lines connected to the solenoid, and tie them to something...as well as it still hooked up at the connector on top of the IM...the computer won't care as long as that stuff is connected (it doesn't know its actually not moving anything)...In your area, you should never have a problem...just be aware that if you do travel to somewhere that gets pretty cold (at or around freezing, or less)...you may have some pretty annoying problems on a cold start, and it won't be very driveable until it heats up to operating temp...thats the primary purpose of VTCS; its a cold start emissions system that works in conjunction with the ecu's fuel delivery during cold starts...all in attempt to reduce cold start pollutants...

The easiest way to never care about it again is to get an Mp3 ecu...that car never had VTCS...and the computer doesn't 'look' for it...so you can rip out everything related to the system and never look back...a forum member can flash the ecu for you for about $150 iirc, but its only for manual cars...but if you're otherwise not in to modding, just remove it from the IM, but keep the 'outside' stuff connected...and it'll be fine...

 

[pinups]

I believe that I am having the same issue..
Anytime hot or cold I get a rattle/squeal at 2k rpm, nothing more then that just a major annoyance. Sounds like a marble in a tin can
Is anyone to put a step by step on how to remove and or fix this VTCS issue?
Thanks!

 

[whatusername]

mine is definatelt not a squeal its a deep rattle more pronounced when the engine is cold and going through 2k- about 4k sounds like my head has marbles in it i still hear it when car is warm but not nearly as loud or as much. and yes im sure everything was put together correctly. my bottem end sounds fine and the head was never messed with by me except the normal cam removal and head gasket swap and everything was torqued to specs.. Hopefully tomorrow it is not raining and i can pull off the IM and eliminate the Vtcs.

 

[Installshield 2]

^^if you do it, be sure and take some pictures of the engine bay before you start...it doesn't look like much at first; but when reinstalling everything and having 10+ odd vacuum lines to route...it might save you a lot of research...

some guys go as far as taping off lines and numbering them, then using MS paint or something to mark the photos...to each their own...but troubleshooting vacuum leaks totally sucks haha...also be sure and use a brand new IM gasket, or be sure yours is in near perfect condition...many guys had problems with vac leaks, but later found out it was actually the IM mating surface itself...and DON'T over torque those IM bolts, the thing is cast aluminum...its soft as hell, you'll strip out the head and/or crack the plenums before you know it...

not trying to freak you out...its not hard work...just no reason to rush it; none of these parts are cheap to replace...

 

[whatusername]

appreciate the info. i have already had the lines off but i will make sure they go in the right spots n make sure they are nice n sealed....

 

[Installshield 2]

^ha yeah sorry, i forgot you actually just put the engine in there anyway...so i'm sure you have all that figured out...

 

[whatusername]

no problem any info i get from u guys is good info

 

[whatusername]

Ok installshield put a hex on me lol i did the port n polish and vtcs delete but i still here the noise maybe valve adjustment? but i also hear a vacuum leak but all is connected and on the pass side i have a plug i cant seem to find where it goes... its on the same harness for the 2 cps sensors towards the back of the valve cover and its black 2 prong with white inside anyone have an idea what it is?

 

[Installshield 2]

white prong? You sure its not a winsheild washer line?

and haha sorry man, didn't try to curse you...I did mention before the work 'we can't hear the sound', so it may not've been the VTCS all along...

as far as vacuum leaks, you're absolutely positive the IM was installed properly with a nearly new gasket? It seems most people that do the VTCS delete get a leak around that more than anywhere else...

any way to get us some pictures? that may help nail down this white prong thing...I know the washer lines use white plugs, and are easily 'popped' out when working around the IM area...I tried to hang my cruise unit by one last week, it popped out with nearly no weight on it...and if i wasn't looking at what happened, it would've taken a while to figure out where that hose went...as it was hanging way down under the IM by the oil filter after it got snagged...I know thats not the vacuum leak answer, but ruling it out just in case...

 

[whatusername]

its not a hose its a plug and its a 2 prong and if u look inside the plug its white..and yea i used a brand new gasket as the other one was crispy n stuck to the im i will try to get pics for tomorrow after work or during break

 

[whatusername]

well the mystery plug was found. i could kick myself lol it was the knock sensor plug.. but the engine noise is still there and definately coming from the head im wondering if it is possible being the car has 204k and was abused by the PO if the cams are really worn or even worse the journals on the head are shot Is it possible? if so how can i fix? new cams? new cam caps? or a new head?

 

[008]

It's piston slap, very common on these engines with high miles. Run 0w-40 synthetic and see if the noise subsides, but it won't go away completely.