CCV Question

[ak-]

Update time,

The good news is my leak down test came back pretty good, all cylinders were within 10% of each other inside the green on the gauge. We did a compression test as well, and all the cylinders hit 150psi and were within 3-5 psi of each other. My spark plugs looked perfect, they were only installed a week ago, but thats when this issue popped up. The sheaths on the coil packs were all white except the one on cylinder 6, not sure what that was about.

We took the crank case filter off and it was gross and full of oil. While off, there was noticeable smoke coming from the port it was attached to, and when we plugged it and opened the oil cap, the smoke was coming out of that. We attempted to blow forced air in to the breather tube, but couldnt hear any bubbling in the oil pan, and didnt hear any of air hissing out of the lines under the breather.

We also found that the outlet nipple on the forge diverter valve was loose, it is a screw in type and it needed 4 turns to get it tight against the valve. One thing we couldnt figure out is why the valve is stuck open when fully connected to the system. If I have this incorrect, tell me, but my understanding is the piston in the valve should stay closed in order to build boost, and when I either let go over the gas to switch gears or decellerate, it should open and release the pressure back in to the intake. Is this correct?

We checked the MAF and it was pretty clean but cleaned it with CRC clener anyway. The intake filter itself was disgusting, unfortunately none of the stores around us carried the new filter, so we got the cleaning kit and cleaned it out.

The stumbling is still at the lower RPM range (1000-2500) and I still dont feel the boost coming on at 4000rpm's like it used to. Could this be attributed to a bad Vanos? We hear no vacuum leaks at all.

Any other thoughts?

Well thank goodness your cylinders checked out! :p

The white stuff could be water on your coilpacks, but I don't know.

When you replaced the plugs, did you purchase the exact same ones that were on the car and gap them appropriately? This can break up ignition and cause stumbles/misses through the RPM band.

Another thing to look at is the CPS (crank position sensor). Apparently they are known to go out as I've been told on 24v motors.
If that checks out, take a look at the toothed harmonic balancer that the CPS reads off of. If it is loose or wobbly, the CPS will get a bad reading and cause the car to stumble. My friend with an s52 turbo e30 couldn't get into boost because of this. He would enter + pressure but it would break up badly and miss till they found out the harmonic balancer went bad.

Your diverter valve stays open/partially open during idle (vacuum). That's normal.

Idk what the smoke could be. Valve guides? I'm not too good with head stuff.

[Xat1cZ]

The valve is suppose to be slightly open at all times except when you're on the throttle, as SC's build, whatever small amount of boost it might be, at all RPM's, so even on idle the valve is suppose to bleed whatever amount of excess boost there is...


edit: yeh what he said^ ;)

[nofattys]

OK, the valve stays open when I am applying throttle, which keeps the car from building boost, but I am unsure why, its such a simple mechanism and the hoses connected to it are unique for each opening, so you can get them confused.

The plugs we bought were the ones recommended to us by TRM who tuned the chip, they also recommended the gap. The stumble was there prior to the plug change, we changed them because we thought there was a miss somewhere, and it had been about 7000 miles.

I wish someone with experience with these motors lived close, trying to explain sounds and vibrations through words is annoying. lol

[e30rapidic]

There is also a weird can of marbles sound between 3500 and 4000rpm

this is classic VANOS noise....does this when it needs to be rebuilt.

check out http://www.beisansystems.com

[ak-]

OK, the valve stays open when I am applying throttle, which keeps the car from building boost, but I am unsure why, its such a simple mechanism and the hoses connected to it are unique for each opening, so you can get them confused.
l

Applying throttle while driving or during idle it stays open?
During idle with throttle, it will still stay open.

Do you have a boost gauge?
Doesn't or barely go past 0 driving? Then yeah, maybe the valve is junk!

Plug both inner/outer holes that the valve goes to and see if you can build boost. It won't hurt if you try a few times.

[Mr.SWISS]

Applying throttle while driving or during idle it stays open?
During idle with throttle, it will still stay open.

Do you have a boost gauge?
Doesn't or barely go past 0 driving? Then yeah, maybe the valve is junk!

Plug both inner/outer holes that the valve goes to and see if you can build boost. It won't hurt if you try a few times.

Yup that or you have a boost leak somewhere.

[nofattys]

I will try it today, someone lent me a Peake Scanner and I am going to see if it can point me in the right direction.

Thanks for the patience, I am trying to learn as much as I can while working on this thing.

[dude8383]

Did you check your O2 sensor too?

Does the car have a charcoal canister? Is there a blockage someplace in the vacuum lines?

[nofattys]

Update....

Brought the car to Levent at Guten during Gfest. The issue with the car not revving past 3500rpm was due to the crank bolt being loose and spinning freely, which caused too much pressure from the SC on the woodruff key, which sheared it in half.

He also found that the subframe bolts were spinning freely and were turnable by hand, so I was lucky to not have dropped the engine during some of my travels.

Parts were coming in this afternoon, so we should know more by close of business tomorrow once they install and test everything.

Levent has been great with his help and knowledge in working with me on this. Very happy with the service.

[ZekeTheSneak]

Yah hes a dope guy and he knows his shit. Good luck man, I would just take your time and go through everything the p/o did and reevaluate even when it is running correctly. Find out if he had a build thread on here as well.

[nofattys]

Ive had my fill of this car, and it is now for sale at Levents shop, I wont even pick it up lol.

[ak-]

Good to hear. Enjoy it some more, at least it's proper now.