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Will a car run with the air cleaner off?

I took the air cleaner completely off in order to get better access to the carburetor but I had to give it so much gas to keep from dying that I had to give that tactic up. Is this normal? It wouldn’t surprise me.

Did you have to undo any hoses? If not, it should run OK, but wear safety glasses in case of a backfire.

Yep, you need to plug all vacuum hoses you disconnected. Did you?

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An engine should run fine without an air filter.
Of course knowing the year and mileage of the pickup AND what the problem was that caused you to remove the air filter to try to do a diagnosis would be a big help. So, exactly what problem were you trying to fix? Any other details that we should know?

I however recommend against driving across the Canadian border without the filter in. Some buddies and I did that (a buddy’s '70 Camaro… in '71 ) and on the way back they pulled us over and took half the car apart looking for the drugs that they suspected us of hiding in the air filter canister. They’d removed the air filter canister cover on our way over and, seeing that the filter had been removed, “tagged” the vehicle to be checked out on the return trip. We were also separated and subjected to intensive questioning while they disassembled the car. These border guards were well trained professionals.

TSMB, this is chapter 10 in the ongoing ‘fix the Toyota carb’ saga. Would have worked much better as ONE THREAD…

I agree.
As a matter of fact, I didn’t catch the connection… and don’t go checking to see if a new post is another in a series. I would appreciate greatly, troll, if you’d keep these efforts in one thread.

No. Thanks.

Air cleaner, not air filter.

I’d appreciate a ruling from the moderators on this. I see this as a separate stand-alone question. Threads run the danger of going off onto irrelevant tangents (somebody wants me to change the oil every year, no matter how little I drive, a comment irrelevant to that thread) and getting too complicated, losing their logical thread.

Can’t speak to OP’s specific vehicle, but I idle my Ford truck with the air cleaner ass’y removed from time to time for testing purposes and don’t notice any difference in idle speed or idle quality. There is one small vacuum hose running to the intake manifold which powers the hot air intake flap vacuum motor I have to plug. I don’t recall having to do anything special besides that.

I should add that I’ve had the truck stall and wouldn’t start when doing this. But that’s b/c some dirt or grime vibrating off something and plugged up something inside the carb. That’s why I try to not do this experiment, or if so, rarely.

Hello. I’ll have to take a much closer look in the morning but it did cross my mind at least some of these threads should be one discussion. But it is past this moderator’s bedtime and I will revisit it tomorrow.

Now we know when the mod’s asleep and we can cut up and talk about home repair and politics! :wink:

@RandomTroll if you are stating that the air cleaner and the air filter are different, please clarify what you mean by air cleaner.

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The steel can that sits on top of the carburetor, has an air intake nozzle, has a hole for the top of the carburetor, hosts the air filter. Mine also attaches to the PCV system and the Hot Air Intake System. I can simply take the air filter out of the air cleaner and run without a problem (for a few minutes while testing - not while driving up a dusty dirt road). When I took the whole air cleaner for access to vacuum hoses I couldn’t idle.

For every gallon of gas your car uses…it also consumes 10,000 gallons of air. Without a filter…it’s now dirty air that’s getting into the engine…and eventually oil.

I wouldn’t do it.

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RT is trying to diagnose a carb problem, so running the engine for a while with the air cleaner removed is necessary for accessing the carb.

RT, if it doesn’t run with the air cleaner unit removed, you may have disconnected something else in the process. As I recall there is one vac hose that attaches to the air cleaner that is short and makes it hard to move the air cleaner far enough away from the carb.

Also, if removing the air filter ass’y removes or disables the pcv valve , that could cause a poor idle.

Hey I have a question I currently have a po171 code on my 2009 Chevy cobalt I’ve checked for vacuum leaks and none. But I took my air intake box off my throttle body to see if it had blockages cause I ain’t drove my car in like 3 months. And as soon as I took it off my car started to die struggling to run. Would that mean it’s getting way to much air to fuel… does it lean to a fuel problem like injector or fuel pump. The funny thing is the po171 leaves and come back periodically!
My question is I’ve took my air intake off many times and no change in idol or how it runs. But when the po171 code appears it’s like you have your hand over the throttle body. WTF Any body have any ideals or suggestions