Rotor R&R - What's the trick?

[Tifosi]

Quote:

Originally Posted by peterlund Can you post a photo of the cap? I once had a cap that was mis-labeled, and it was a real pain in the butt. There may be more of these out there.

[Vintre]

Well.....car is running smooth again!

Went back to scratch. Disconnected everything and re installed again. Figured it couldnt hurt.

I noticed that oil vapour recovery hose that runs from the cam cover to the oil vapour recovery cannister was cracked, so I replaced that.

Now the car runs good again. Amen!!!!!

I'm not sure if something was off or if it was the hose.

Do you think that if the hose was cracked, barely hanging on, would cause a rough running engine?

Anyways, I'm back on the road again! Thanks to everyone for their help. This is a great community to be a part of!

[Tifosi]

Depends on how bad the crack actually was.

If it was well and truly leaking, (as in 'like a sieve'), then it would allow outside air to get into the seperator where it would be picked up in the vac hose that goes to the plenum and create a minor false air leak, though not as drastic as one that derived from any of the 'dry' air hoses, (pressure regulator line, charcoal canister line, vac advance line, or any of the hoses and tubes up on top of the engine).

It's also viable that the leak was only bad enough to cause an imbalance in base pressure, which in turn would cause a bit of odd running, though likely that would be relegated to the idle and just off idle RPM ranges. Break over 2500-3000 RPM and it would seem to 'get better' persay.

Query: after all that, you do have the 3 vacuum lines on the frotn end of the plenum plugged onto thier correct nipples don't you?

They are oraficed and positioned specifically for what purpose they serve.

Topmost one which has the smallest hole goes to pressure regulator
Middle is for the charcoal canister and has the biggest hole
Bottom is for the seperator and has the same size hole as the one at the back of the plenum that's used for the vac advance line


To give yourself a comparative idea of what the crack in that hose could have been doing now that things seem OK, warm up the engine then remove the oil fill cap and note how the idle speed and engine pitch changes.