Mike90SE

iTrader: (3)

I have grounded my vtc's, and i even soldered the connections, but why around 4-5k rpms do i still feel a surge, not all the time but vast majority of the time, and a lot here lately you can hear the vtc clacking terribly, i thought grounding the vtcs was suppose to completely disengage the vtc's therefore there wouldn't be any clack or surge?? any ides??

mikekantor

iTrader: (5)

I think they are supposed to transition the cam angle lower than 4-5K, so it might be something else.

Edit: nevermind, I checked and I'm wrong, its at 4600.

Wiking

Haven t played with this particular device, but generally the following problems may be found:

Electronically controlled valve typically has a coil. When both + and gnd are connected, current flow through the coil causes a magnetic a field inside the coil. This field pushes-or-pulls a iron 'rod' inside, this forces a valve to another position. If no current flow, no magnetic field, no effect on the valve... When +or- is missing or coil broken - then no current flow... usually these can be measured easily without dismantling the system.

Typically a spring forces the valve into one predetermined position when electronics are 'off'. If spring is broken, position will be arbitrary, effects not desirable.

The valve itself can be broken may ways; leaking or jammed shut or smtg else - flapping in the 'wind' (taking cues from microsoft stocks?).

The valve controls flow, here oil (pressure). If that is missing or intermittently blocked, doesn't help if all previous thingies sing perfectly in chorus...

maximaman1313

grounding VTC's from what I've heard does not completely get rid of the clacking. I guess if you ground them out when it first begins to clack you have a better chance of getting rid of the noise, although you still may get it eventually. I know Mikekantor said at 4600. But I know on my VE it kicks in at about 3400-3600 rpms.


mikekantor where did you see it say 4600?

maximaman1313

from what I remember its the spring inside the VTC assembly that goes bad for some reason. not sure if rebuild kits are still available or where you can get them at. but if the clacking happens all the time, then you can either get the vtc's repaired (no idea what this cost, not cheap unless you do it all yourself) or maybe even look into just swapping a jdm motor in, thats what I did, and I've been clack free for about 4 years now. Or you can just turn the stereo up I believe the VTC still work and will get the performance gain from them even if they clack, but aren't grounded.

I have no idea why your getting surge at 4-5k

Wiking

...take out, weld em solid?

mikekantor

iTrader: (5)

FSM, section EF & EC, page 176:

VTC Solenoid Valve is ON when these engine operating conditions are met:
- not at idle
- coolant temp is below 110C (230F)
- engine speed is below 4600 rpm
- engine load is high
- selector lever is other than N or P

When the solenoid turns OFF, timing is retarded and the torque curve is moved up to higher RPM.

mikekantor

iTrader: (5)

If you go that far you might as well pop in the new spring and drive happy. Also you wouldnt want to risk changing the rotational balance of the intake cam by welding the VTC.

maximaman1313

there is a nissan TSB on this.

take them out, use a rebuild kit or whatever, I think its a spring. you need to use a press to get the new spring in there and make sure you line it all up. definately don't weld

Wiking

Best is to do always the best as u say. Smtimes thats not an option...

Welder has to be pro = not me, he knows the relevant issues, can deliver. All depends on the price/wallet; if the stealership VTC-bits cost 10x the car value, try welding - or turning on more volume...

My guess: the bigthick wallet guys dont read 3gen forum?

maximaman1313

so BELOW 4600: that means above 4600 they turn off ? meaning the surge can kick in anywhere from above idle to 4600 as long as the other things meet the condition.

mikekantor

iTrader: (5)

$40 / VTC for the spring and cover. It can be done with a small vice, no press needed.

maximaman1313

I think you were right the first time.. it does transition before 4-5k. It goes back to default above 4600rpm's tho right?

shoult

iTrader: (1)

If I remember right (this is memory from 5 years ago) the kit of parts seemed to be pretty inexpensive, like $50 or less. It was having the service DONE at the dealership that cost bazoodles.

Personally, the clacking VTCs don't bother me all that much. I can't here them over the clacking CV joints anyways!

Wiking

If that corrects the problem, the welder lost

Wiking

...weld em together?

I guess its time to get lost - in sleep.

Greeny

iTrader: (43)

Mike, I would just let'um ride as they are until you replace them with your new assemblies.

The grounding procedure only works for minor clacking issues, once the springs get so worn the grounding procedure really doesn't work that well anymore. Yours are just probably past the point of help.

you may also have a bad knock sensor causing some low end lag, check your ecu for k/s code, as it(the k/s) usually leaves a ghost code(no cel)

92 Max

Clacking can also be due to a bad timing chain tensioner. Sounds the same. The TSB for this should be up in the stickies.

Mike90SE

iTrader: (3)

Thanks everyone for the good advice....but I think I will take the side of Greeny here. But....could this also be an oil pressure issue as Wiking alluded to earlier? Does anyone know what the oil pressure is supposed to be once the motor is warm? Because my VTC's are absolutely silent until it warms up.

1992maximase30

iirc the ve makes it's power @ high rpms.
so to take care of the lowend the vavle timing is advanced below 4600rpms.
and the guy in the how-to for the vtc ground did say his clatter would range from 30-60 seconds.

i had the vtc clatter and i had them bad.
i changed the oil and added engine restore.
did the yota filter mod too.

worked for awhile but they came bad and was even worse.
come to find out the harness for the front solenoid was dirty/corroded.
cleaned them and it went away.

as for the timing chain a loose timing chain and vtc clatter are two different sounds.

Greeny

iTrader: (43)

Mine do the same as yours. (cold startup clack for a few seconds, then silent.but after driving for a while, clack clack clack)<--though mine are not as loud as yours. The ve oil pump is quite long lived, so i seriously doubt oil pressure is the issue here, just extremely worn vtc spring assemblies.

1992maximase30

damn mines was weird compared to yall's.
nothing when cold.
nothing when hot.
just in between.

internetautomar

iTrader: (30)

mine rarely clacked at all, a couple seconds on start up.
the maroon one clacked ALL the time, but it went to someone else that way. uncle wanted to kill me for buying that car, too much rust. Wayne got the seats from it.

Mike90SE

iTrader: (3)

Hmmm, something else to consider too.

Mike90SE

iTrader: (3)

Meh,when mine is stone cold, they do not make a sound. but they raise 400 sorts of hell once it warms up and is allowed to idle for about a minute.

So, considering I have the new sprockets, what is it (ball-park figure) going to cost me to swap them suckers out?

Greeny

iTrader: (43)

Buy new chain tensioners for sure, not sure on the price on them(check courtesyparts for pricing)

Check the vtc write up in the stickies for any other parts you may have to buy for the job, probably not much.

MrGone

iTrader: (30)

same deal, silent cold, warmed up idling at a stop light and they'll start making noise. Put a load on the motor (or ground them for a bit if you have it on a switch) and they quiet down.

Rebuild kits from the dealer are typically about $35 each. misc gaskets and other stuff for preventative maintenance also add to the cost.

MrGone

iTrader: (30)

welding them is not feasible

you'd be better off putting a piece of tubing inside of them to prevent them from moving but even then I wouldn't really recommend it. If you're going to go through the work to the point of having them off the engine you might as well install new springs.

Mike90SE

iTrader: (3)

Well, I bought the new sprockets from SurraTT. Just been waiting until warmer weather and mo' money before I tackled the job.

Mike90SE

iTrader: (3)

Not to argue, but while I agree that the oil pump does pump the oil, I was always told that the bearings (rod, main and cam) were what actually made the pressure due to the amount of clearance they have when new compared to when they are worn. I used to have an old Dodge Lancer that had the 2.2L in it and when it was cold it had perfect pressure, but once it warmed up.......it would barely turn off the idiot light. And the motor sounded like a pea thrasher. And the bearings were shot in that thing. LOL

Wiking

If no problem with oil pressure light, the pump is probably healthy.

Flow can become Blocked: My Opel valves were shot after Fram filter change - there was (!? where it came?) a plastic part that was pumped into oil channels, blocked oil channel and this block (=no lube) killed the hydraulic lifters. When no lube, such wear appears in just few thousand miles.

Pressure drop: if actuator parts are worn, pressure may drop in the actuator as oil pressure 'escapes' before doing its duty... This may cause myriad problems.

General solution: Buy a A/T VGE, no VTC-chainy clicety claceties, sticks...

maximagician

when my ve was all dismantled i compared the cam sprocket on the exhaust
cam to vtc sprocket on the intake cam briefly and it looked the same circumference
,teeth shape\count and the "key stud"thing that locks it to the cam looked similar
so one MIGHT be able to use two "non vtc exhuast cam sprockets"
....BUT if you that far in might as well rebuild the vtcs esp.now that wiking mentioned
doing it in a vice instead of needing a hydraulic press
we should call the ve a quad(4)cam engine since its a v-6 with two cams on each head
took my ve for a ride today and even after sitting a few days the vtcs are still not clacking,although i only hear em SOMETIMES when parked uphill or side hill or very cold out but they still dont ALWAYS in these instances,guess im one of a lucky few left oh and i leave my oil 1\2 quart over ,no specific brands either

internetautomar

iTrader: (30)

The VE is a Quad cam (4 total cams) or Dual Overhead Cam motor (2 cams over each head)

Greeny

iTrader: (43)

Well mike, the only oil pressure related issue with the vtc's would be clogged oil galley's, usually from lack of proper oil changes. The oil galley's that feed the vtc's oil are extremely small, the vtc's tsb explains the cleaning of these galley's.

Galley pic below..

mikekantor

iTrader: (5)

LOL I love how they got the Nissan burger outline on the bottom of the valves! Never seen that view before, but I have a feeling mine have more carbon.

Mike90SE

iTrader: (3)

Well, you saw the donor car....do you think the motor was cared for as it should have been. Ima thinking probably not. Heck, when I replaced the injector last Saturday, I also replaced the PCV and it looked as though it was the factory one. Gummed up is an understatement. The valve inside of it would barely move at all. So, I feel I have a loooooooooooonnnnnggggggg rode ahead of me before I get this motor ship-shape.

Mike90SE

iTrader: (3)

Did I make everyone mad or something? If so, I'm sooorrryyy....(in the best Peanut immitation)

mikekantor

iTrader: (5)

Why? What happened?

92 Max

as for the timing chain a loose timing chain and vtc clatter are two different sounds.[/QUOTE]

Unfortunately, unless a person has experienced both VTC and Timing Chain clack separately, there's no way to audibly decern the difference. All you know is that there is a clack. I had a clack that I assumed was the VTC and did the Timing Chain Tensioner test from the TSB, just to be complete, and was surprised to find a bad tensioner. This allowed the chain to slap against the guides and clack. Based upon this I may never have heard a VTC clack (I rebuilt them).

Mike90SE

iTrader: (3)

Nothing that I am aware of. I was trying to find out the actual oil pressure from a gauge and everyone quit responding. Thought I had touched on something taboo. LOL