What are the chances this is the reason I've been burning tons of oil? (PICS) - Third Generation F-Body Message Boards

Darkshot · 01-12-2009, 10:59 PM

My 91 L98 (152k) pukes blue smoke when warm. On cold start, it doesn't spew any smoke at all. But once it's warmed up it will spew blue smoke when I rev it and it spewed smoke all through it's smog test today (failed). If I park it hot and restart after 10 minutes, it lets out a nice puff too.

I pulled the intake manifold and found what seems to be a gasket that was letting oil get sucked into the intact tract. The bolts weren't very tight either - I probably could have taken them off with a screwdriver.

In the second pic you can see my finger wet with oil - that's from just rubbing my finger along the walls of the intake runner.

This ad is not displayed to registered members.
Register your free account today and become a member on ThirdGen!

Jimmy D · 01-12-2009, 11:10 PM

Apeiron · 01-12-2009, 11:19 PM

I can't really see a problem

Darkshot · 01-12-2009, 11:54 PM

My finger is wet with engine oil from inside the intake runners of the TPI base.

Apeiron · 01-13-2009, 12:01 AM

Your gasket sealing areas look ok though. Some oily residue inside the intake is normal.

Darkshot · 01-13-2009, 12:20 AM

I realize that due to PCV, but there's one that's clearly worse than the others. That plug was a little "worse" than the others too. I guess I'll know once I get it back together.

CBR1000RR · 01-13-2009, 03:29 AM

I didn't really see a problem. Everyone I've taken off with 100k+ miles on it looks the same as that. Let us know how it comes out when you get it back together.

paulo57509 · 01-13-2009, 09:12 AM

There was a TSB regarding warped TPI manifold bases.

I don't recall the exact wording of the TSB, but I do remember that "threading" in the manifold bolt holes near the front and rear water jackets is evidence of the manifold being warped.

I think the TSB came out in '88 or '89 and included a new manifold part number. I would think that your model year would have gotten the newer part number from the factory.

The manifold on my '87 was warped and sucking oil. I was also getting a light throttle ping.

When you get new gaskets, I'd recommend installing Fel-Pro Print-O-Seal gaskets and not the Perma-Torque.

BTW, what happened to the heat shield that's supposed to be on the bottom of your manifold?

1987ZTPI · 01-13-2009, 10:35 PM

$20 says it's valve seals. very common on our cars. the best of them do it. if the manifold gasket was leaking you will notice a surging or, hesitaion or high idle from a vacume leak. 152miles is alot

Darkshot · 01-13-2009, 10:53 PM

Couple things:

She never smoked on cold startup. It wasn't until warm that the smoking started, and only when I would rev it up or drive it.

If I let it idle for 10 minutes hot and revved it, a big puff would come out on the first 2 or 3 revs then stop smoking until I let it idle 10 min again.

When I took the intake manifold off, the passenger side bolts seemed rather loose. I could have taken them off by sticking the right side flat-head screwdriver into the TORX hole and turning it by hand.

paulo57509 · 01-14-2009, 03:36 PM

Quote:

Originally Posted by 1987ZTPI

$20 says it's valve seals. very common on our cars. the best of them do it. if the manifold gasket was leaking you will notice a surging or, hesitaion or high idle from a vacume leak. 152miles is alot

I forgot about this one. I vote for this too. In fact, I looked back at my records and I too replaced the valve stem seals (both intake and exhaust) with positive-type seals.

In retrospect, I should have just left the umbrella seals on the exhaust valve stems.

It tough getting old....the memory is SHOT.