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Damage from missing cylinder?

My mechanic said one cylinder isnt working though we havent done any checking beyond wires. It’s not worth putting money into but I cannot afford to get anything else. Will driving on just the 5 cylinders create increased damage or other issues that will get me stranded? it starts right up, is rough but levels out after a couple minutes It is smooth driving under 40mph, but acceleration above that creates shaking and check engine light flashing, no ominous ticking noises but can tell not firing on all cylinders. Problem is I will have to drive it highway speeds at some point-tried it before and made it-was able to eventually baby it up to the required traffic mph with the shaking diminishing and smoothing out but rattling started up again every time I had to hit the accelerator to increase the speed. What can I expect by continuing to drive it?

Eventually the unburned gasoline will mix with the oil and greatly reduce the life of the engine (which may be toast anyway). Could be days, weeks, or months. Limit your driving until you can get it fixed.

What kind of car are we talking about? Mileage? Age?

Key words: “I can’t afford to get anything else.”

Each cylinder needs 4 things to work right, air, fuel, compression, and spark. I assume the cylinder gets spark as you mentioned he checked, and air is typically a given. So, put a few dollars in to check compression and the injector.

Letting it run like this will cause very expensive problems in the near future. I can see raw gas contaminating the catalytic converter, burning it out or melting the substrate to a clogging lump, oil contamination causing lubrication problems, an engine shaking itself to death, and other unpleasantness. And all may be avoided by replacing an injector or connector, or even adjusting the valves. Heck, it could even be a bad spark plug, leaking spark before it gets to the tip.

What does “checking the wires” mean. Did he pull the spark plug? If not, i’d at least do that, you would recoup the cost of a new plug in short order with the increase in gas mileage.

A flashing check engine light means the engine will not be running much longer if the problem is not addressed.

I guess I wondered the same thing that Keith did; why, exactly, isn’t that cylinder firing?
A cylinder not firing is not a “must tear the engine apart” repair. It’s likely something simple and affordable like a plug, a coil, or an injector. NOT fixing it will usually cost you much more than fixing it. Can you tell us more?

Disconnecting the injector to the bad cylinder may help in the short term by stopping the flow of raw gas into the exhaust.
A compression test is not very expensive and will tell you if it’s a serious mechanical problem.

If you really want to drive the 6 cylinder motor on 5 cylinders (bad idea to begin with) you must stop fuel from getting into the bad cylinder. Find the bad cylinder and disconnect the fuel injector. At least this way you won’t put excess raw gas into the catalytic converter. Excess gas getting to the converter can overheat the converter and be a hazard, as in fire hazard.

Running on the remaining 5 cylinders will be bad for the motor but will kill it slowly. You won’t be left on the side of the highway going on 5 cylinders.

A misfire will quickly ruin the catalytic converter. Mine was $700.

@neboshoh I will assume you can’t or won’t spend money for a proper diagnosis.

In that case, I suggest you replace the plugs and wires.
Perhaps you’ll luck out.