Engine sounds like a kazoo now, suspect broken intake valve spring

[jc179]

After doing some work on my car, to get it running right, and no longer missing,however the other day, It started to feel like it was "missing" when in the off throttle situation at any temperature. 

 

So coasting, feels a bit touch, can feel the shifter shaking. Under WOT, things are OK, and don't appear to be missing, or at least I can't feel it. I also have this very odd sound coming from the plastic intake which sounds like a kazoo.

 

I took a video, at the moment I suspect I've broke 1 or 2 intake springs and the valves aren't fully closing.

 

The car does idle smoother than in the video , but the rev's are jumping up and down as I've pulled off the MAF pipe.

 

 

 

I've had a broken spring on the exhaust side before , around 250,000 km ago.... and that was easily noticeable by the unusually hot exhaust coming out of the exhaust at idle on a cool start. 

 

I talked to the dealer, and they said for 99/2000 models  *NEW* valve seals or guides are needed as the spring design has changed... this wasn't the case last time and I just swapped the spring.

 

any ideas on that , if that's still the case , or I do actually need new seal/guides for the valve to fit the spring?

 

Edit #2

At the end of the video you can see the paper towel infront of the intake sucks in... and seems to blow out a bit also supporting the idea something bad's going on.

 

Video 2 with tubing attached, steady idle, and humming sound.

 

http://youtu.be/zvJktyb9hpl

 

 

thanks

Jonathan

[Blackmage]

do a compression or leak down test on all your cylinders

[jc179]

Yeah that's the next logical step, aside from anything obvious being broken....

 

Dang it why do cars *always* break when its cold outside, I mean I can't blame them, I don't want to move either....

[Tabres]

Leak down test should tell you real easily if its an intake or exhaust spring, too..

[ttocs]

that is a pretty tripped out kazoo.

[jc179]

First, some interesting things, compression tests show pretty good, 190-180-190-185-190-185 (order front to back drivers side, then psgr side).

 

Still not sure what's #1, or #2 nothing labelled. So, those looked relatively good until I got the leak down tester made, and then the bad news shows up.

 

Same order; -> means leaks down to, left side = input, right side = leak down pressure.

PSI 70 -> 65 [ok], 70-65 [ok], 70-65 [ok] , WOW drivers side of the engine looks good, passenger side 70->65 [ok], 70 -> 50 [not so ok], 70->20 [terrible].

 

When doing the leakdown test, I can hear and feel the air escaping into the intake ports at the top of the head with the intake off.

 

 

I suppose at this point, the best I can try is either drive it as is, or pull the springs and try to lap the seats by putting the valve end in a drill and spinning the valve/ pulling up?

 

Otherwise, what's a new popular swap these days? Anything *easy* ? I'd like to make it more worth while if I go down that route...

 

thanks for any suggestions

 

Jonathan

[Blackmage]

the compression tests seem within spec honestly. isnt it up to like a 15% difference is acceptable?  

 

but that leak down test sounds like a leaky intake valve if thats what you were hearing. interesting that the compression test came back relatively OK but the leak down test showed some issues.  

 

im not sure what the kids are doin these days with the new edge v6's, but sounds like something will need to be addressed at some point.

[jc179]

Well, tried very quickly last night, managed to get some improvement, from about 18 to hold 25 psi now, will have keep going atthis and see what, if any further improvements happen.......

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[jc179]

Hi all

 

Need some help, I can't believe I have to ask about reinstalling rocker arms... but first an update.

 

After cleaning things up, I have all 6 cylinders performing as they should in a leak down test, they lose about 6 psi per... not too bad. I am not sure how long this will work if at all... so I really to try starting the car... BUT

 

.... my question is "Is there any lash adjustment" ??

 

So here is where I am currently stuck. When the specific cylinder I'm working at is at TDC with both valves closed, I can usually rotate the pushrod, as its not under tension. In this case the pushrod is actually pushing the rocker arm up, and opening the valve.... and no compression - leakdown and compression test confirm this as well for the 2 cylinders I touched.

 

I've checked the obvious,  but here's my list - checked:

- that the keepers are correct (I couldn't actually get them backwards if I tried due to their triangular shape),

- all pushrods are equal length (I never removed them anyways)

- I compared the height of all the valves on that side with a straight edge ruler - they are all at the same height, so this indicates to me I didn't pull one up too far when I spun it?

- I've made sure the pushrods are seated into the lifter? down by the cam, and properly in the rocker arm

- Made sure when tightening down rocker arm the square part sits in the vally in the head.

- tried rotating the engine numeroius times on starter, no changes

- left the rocker arms installed overnight, thinking just maybe there's some sort of hydraulic lifter down there that needs to bleed down... no change.

 

At this point I am so frustrated, I can't figure out what I've done wrong. I pulled the keepers and springs off again  just to double check  it all.

 

If there is no lash adjustment, should I just try starting it and let it warm up, or shim the rocker arms with washers, ugh.... :facepalm:.

 

thanks for any suggestions "installing rocker arms"  ...

 

 

 

 

 

[Blackmage]

ugh i wish i knew more about the sixxers.  hopefully someone can give you some info....

[jc179]

Hi All

 

Just wanted to post a follow up. First, I have to admit I made a mistake reinstalling the idle valve,  (installed it backwards) and that's actually what causes that funny noise..... after flipping it around again, things sound OK.

 

I've reassembled the car now, and am going to try running it a few days... basically some of the valves seem to be stuck open a bit, going to see if it settles down. It's drivable, but has a slight miss (engine shake) at idle intermittently, and part throttle.

 

I am totally going on a WAG here, but it seems to be there maybe some electronic gremlin now involved in the mix.

 

As I figure out bits here and there I'll update back... but at least if anyone else ever hear's that noise... well now you know!

 

Jonathan

[Blackmage]

oops!!