zavalo

The car is an '88 Accord LX that I've owned since new. It has the carburated 2.0L engine I belive is ID'd as 1955. It has 208,000 miles on it.

Both rough idle and high oil consumption seemed to show up at the same time. At first, it would not idle at all. I replaced the intake manifold gasket and now it will idle rough when warmed up, but have to nudge the throttle the keep it from dying when cold.

The sudden increase in oil consumption showed up at the same time. It will consume up to 1 quart of oil every 300 miles. It's not leaking any oil. It doesn't smoke from the exhaust either.

I thought at first that it was blowing oil out the crankcase through the PCV into the intake. But the intake is clean and dry and so is the PCV line. When I disconnected the PCV line, the crankcase will pull a vacuum if I hold my thumb over it with the engine running at idle. I don't know if that's normal, but at least there's no blow-by. At idle, the PCV side on the air cleaner seems to be very slightly positive pressure when I cover it with my thumb.

I replaced the dist. cap/rotor/wires/plugs. The old plugs all looked the same without much fouling.

The sudden high oil consumption is what concerns me most. I havn't ruled out broken piston rings but it seems to have good compression and there is no loss of power. I would think if the rings were bad, there would be some crankcase blow-by. The oil seems to be getting into the combustion chambers somehow. Could you loose that much oil from worn valve guides? I would expect gradual loss of performance from an engine with that high milage, but this came on all of a sudden.

Anyone have any experience with this and a possible suggested remedy?

Stew Pidasso

I'd do a compression test before anything.

briq4

Could it be the head gasket? Oil is leaking into the coolant? Just an idea.

zavalo

Thanks for the input guys.
The coolant is clean and at the correct level, so I don't think it's the head gasket.
I don't have the tools for a compression test so I'll probably let the dealer look at it.
I was just wondering if there was something simple like a bad PCV valve that would cause this problem.

Stew Pidasso

I just bought a compression test guage. $25 bucks at Autozone.

89_LXi

I got a real nice compression gauge at Sears for around that price too. It screws in, and has a 1 way valve to hold the highest pressure so you don't have to try and read it while cranking...real nice

If it's not burning or leaking, then it could be a PCV problem. Have you done a manifold vacuum test to make sure the PCV valve is even able to operate properly? It should be a steady 17-22 in-Hg, I believe. My moms '94 Accord went for awile where it was going through alot of oil (it wasn't the seal -- that had been fixed). Wasn't burning, wasn't leaking, just dissappearing, lol. Then all of a sudden, after doing that for about a year, it just seemed to fix itself and stopped going through oil altogether. I have no idea what it was though, lol. If you've got a few miles, it could be your rear main crank seal. If there's some oil right where the transmission mates to the block, then that's leaking while you're driving. Mine only leaks a little bit (usually 1 quart in 5000 miles, and that's with synthetic, so very little), but if it's bad enough that could pump the oil out pretty quick.

89_LXi

On a second re-read through your post, it does sound like some kind of vacuum leak. Those POS carbs have TONS of vacuum lines, and any of them can cause probs (god I love EFI, lol). I'd say a vacuum test is definitely in order.

Desslok

Are you sure it's not hte other way around? THe IM should be pulling vaccuum, not hte crankcase.

89_LXi

Yea, the crankcase should be pushing out fumes and pressure, and the PCV sucks it up and into the manifold for recirculation. When I pull the PCV out of the breather chamber tube on mine, you can feel the air coming up and out, and it smells like gas fumes (probably because it is, haha). Check that out

zavalo

Hey thanks for all the replys guys. I appreciate all the input.

Yes, the crankcase is pulling a heavy vacuum. When I disconnect the hose between the valve cover and air filter housing, the valve cover side sucks and the other end does nothing. (I assume this is the PCV line?) If the PCV valve is located on the air filter housing, it is probably bad because it doesn't draw any vacuum. But I still don't know why the crankcase is pulling such a vaccum and I am thinking that must be linked to my heavy oil consumption.

Thanks too for the heads-up on the compression gauge. I didn't know they were so inexpensive.

zavalo

Dontcha hate it when people start a thread asking for help, and never post back with the resolution?

Resolution to rough idle and high oil consumption:

The rough idle was caused by a broken PCV valve, which created a huge vacuum leak. Also, the distributor vacuum advance had a bad vacuum leak too.

The high oil consumption was caused by the broken PCV valve letting the intake manifold vacuum suck the oil out of the crankcase.

briq4

Thanks for updating! Glad it wasn't anything major, seems like your going to easily make it to 300K