Rough idle and dying at stops

[User927]

I have an 85 accord and I am beginning to experience some potentially large issues. Recently, the car has been idling rough and bogging down at stops (automatic transmission), sometimes to the point of dying out. It has also been having issues getting up to speed(underpowered).

The car burns a lot of oil, so my guess is that the previous owner had it under the recommended level for some time. After getting the oil where it should be, the car runs a little smoother, but still not 100%. I've tried spraying carb cleaner everywhere to test for vacuum leaks, but I haven't noticed anything. I have also put some fuel system cleaner into the tank in hopes that it cleans anything that may be inhibiting the engine. Car is bone stock with 80k miles.

What could the problem be? What can I do to further diagnose the problem? Thanks

EDIT:
I read that I should be able to figure out whether the problem is the brake booster or not by plugging 'it' with a golf tee, though, it doesn't go into much detail as to what I'm plugging. Since the engine provides vacuum for the brake booster, that would imply I should be plugging the port on the engine. Since there will be no vacuum for the booster, braking will become an annoying task. Is that right? Is this a safe way to diagnose the problem?

[2ndGenGuy]

Just wondering about a few basic things first:

Have you checked timing? How are the plugs and wires, cap and rotor?

Are the chassis and engine grounds clean? Battery terminals?

When was the last time the fuel filters were changed? There is one at the rear under the car next to the fuel pump, and one in the engine bay.

There's also a knob on the back of the carburetor underneath the air cleaner (dig way up in there, you'll find it). Have you tried bumping up the idle a little bit? I know that won't solve the rough running or lack of power though.

[User927]

I'm not entirely sure how to check the timing. The cap, rotor, plugs, and wires are new. I'll have to check the grounds when I get home. I'll order the fuel filters and replace them this weekend. Is replacing them on this vehicle particularly difficult?

[2ndGenGuy]

Nope, it's pretty easy. The rear one is just up under the left side of the car by the wheel. The front one is right in the engine bay near the carburetor.

You will check the timing through a tiny view hole that lets you see the edge of the flywheel. It should be pretty close to the number tag on the engine block.

[User927]

So I've finally gotten a moment to sit down and order some parts. I'm looking at fuel filters on Rock Auto and I noticed that there are 2 different forms for the primary filter. Pictures below



Which of these are correct? All the secondary filters look the same, so it's just a matter of brand from there. Any suggestions?

Also, I noticed another symptom today on my drive home from work. When the brake is engaged, the RPMs drop. The harder I press, the more it seems to drop. This happens regardless of gear (drive/neutral). Hope this helps diagnose the problem.

Will work on getting the grounds in shape and learning how to check the timing on a car. Yay YouTube. Looks like I need to invest in a timing gun.

Thanks

[2ndGenGuy]

Also, I noticed another symptom today on my drive home from work. When the brake is engaged, the RPMs drop. The harder I press, the more it seems to drop. This happens regardless of gear (drive/neutral). Hope this helps diagnose the problem.

BAM! That is the symptom that tells us exactly what the problem is. Do you hear a hissing noise from your brake booster? It is likely that the booster is toast, and when you hit the brakes, it's creating a massive vacuum leak and the car can't idle.

As far as the fuel filters go (it might be good to replace them, even though it doesn't sound like it's your problem). The bottom pic you posted is the one that goes in the rear of the car. That top pic is for a fuel injected car (the SE-i), it will not work on yours.

[User927]

Sweet deal (sorta...). I'll have to figure out where the booster is on this car and see if I can hear any sort of hissing. I'm pretty noob when it comes to cars, so I appreciate the help. And yeah, filters will be good to replace as I'm not sure when they were last replaced if ever. Seattle is finally having some nice weather so I can work on the cars.

[2ndGenGuy]

Sweet! Seattle eh? Cool to have another local on board! Where abouts are you? I actually live in Maple Valley...

[User927]

I'm actually in the Newcastle/Renton area. Now that I know where to listen, I can actually hear a hissing by the brake booster/ master cylinder area. Hopefully it's just a shitty hose...

[2ndGenGuy]

Sweet! Pretty close by! I'm afraid to say it's probably not a shitty hose.

Just re-reading your previous post. The burning oil is probably just the valve seals. Mine did that quite a bit too, burning off mostly from stops. I wouldn't worry a ton about it unless it's billowing clouds. Mine ran forever like this.