Screeching after a plenum install
Screeching after a plenum install
Long story short, I cracked my upper plenum tightening a bolt (always read the instructions on a torque wrench!), and just today reinstalled a new-to-me one. Everything came off smoothly, I reattached all the vacuum lines and the coolant-bypass lines, everything torqued down to 50 or so inch/lbs (correctly this time), but I have a horrible screeching on startup with some code thrown (I have an OBDII reader in the mail). The screeching is coming from the driver side of the bay; after 5-10 seconds, the engine chokes out and dies.
Some coolant spilled onto the driver-side valve cover when I was disconnecting the lines and also got behind the engine, so I'm thinking that it got on something/in something. However, I don't know what is on the backside of the engine; all the belts are up front, and AFAIK there's no exposed moving parts back there. I'd imagine that coolant couldn't just drip into the sparkplugs, but I'm no expert on that. On a related note, there's a gold screw-thread on the end of the valve cover closest to the driver, but I removed nothing from there; is it supposed to be exposed (no pictures currently, sorry).
I'll check the intake tomorrow morning in-case there's a leak that I'm missing, but everything seemed hooked up correctly. I did attempt to crank the car once without the TB plugged all the way in, but the screeching sound happened then and after, so I don't think that's the issue.
I checked oil and coolant before first start-up, both were at the correct levels. MAF looks clean, installed facing the correct way. I had cleaned up oil in the lower plenum, but quintuple checked that there was nothing left when I put the spacer/upper plenum (and gaskets) back on.
It's definitely not the belts, but I'm at a loss to what it could be. 99% sure it's the driver-side of the engine, though.
Some coolant spilled onto the driver-side valve cover when I was disconnecting the lines and also got behind the engine, so I'm thinking that it got on something/in something. However, I don't know what is on the backside of the engine; all the belts are up front, and AFAIK there's no exposed moving parts back there. I'd imagine that coolant couldn't just drip into the sparkplugs, but I'm no expert on that. On a related note, there's a gold screw-thread on the end of the valve cover closest to the driver, but I removed nothing from there; is it supposed to be exposed (no pictures currently, sorry).
I'll check the intake tomorrow morning in-case there's a leak that I'm missing, but everything seemed hooked up correctly. I did attempt to crank the car once without the TB plugged all the way in, but the screeching sound happened then and after, so I don't think that's the issue.
I checked oil and coolant before first start-up, both were at the correct levels. MAF looks clean, installed facing the correct way. I had cleaned up oil in the lower plenum, but quintuple checked that there was nothing left when I put the spacer/upper plenum (and gaskets) back on.
It's definitely not the belts, but I'm at a loss to what it could be. 99% sure it's the driver-side of the engine, though.
You probably pinched the oil fill neck between the upper and lower plenum and the "screeching" is actually a really high pitched whistling as its sucking air through the gap.
Oil fill neck, got it. Where exactly is that on the plenum? I'm guessing I'll need to take everything off again.
EDIT: Wow nevermind, that's the place you put the oil. I was thinking of some hose in the back or...something. Will check out and report back.
EDIT: Wow nevermind, that's the place you put the oil. I was thinking of some hose in the back or...something. Will check out and report back.
I swear you guys are clairvoyant sometimes. Oil fill neck had gotten stuck underneath my spacer. Vacuum leak of that size explains how I was smelling oil. Fired up perfectly, bout to go test drive. Thanks!
Joined: Mar 2009
Posts: 18,299
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From: By the sea, Tx
G35 sedan w/ too much money in mods

Meh about Cleric, it's one of the most common mistakes made when installing a spacer.
Runs and hides, Cleric really is one of the most knowledgeable and helpful members we have here.
Runs and hides, Cleric really is one of the most knowledgeable and helpful members we have here.
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When I installed mine, it was the driver side valve cover hose that got squeezed that was causing the vacuum leak cuz I disconnected the part that hooks into the ztube.
He got it figured out, unless you're just sharing your experience, that never hurts! I was just wondering why @socal04g35 has his manifold off enough to feel the need to cut the oil fill neck
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