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Car stops accelerating

Hi, I drive a 2002 Toyota Rav4. Recently my car developed a tendency to stop accelerating while driving. What i mean is, I m cruising at say 60mph and then notice that my speed is dropping, I step on the gas and nothing happens. Eventually my car slows to a halt and theres not much i can do to prevent it from doing so. Funny thing is, I turn it off, then back on and it drives again ( stepping on gas makes it accelerate). This happens every 30 min of driving or so. It also happens when im stopped at a light (car wont go when i hit the gas) and abrupt braking will trigger this effect as well. My check engine light is on, and been on for a while, and when this phenomenon occurs the battery light and oil light turn on also (but are not lit when i restart the car. Does anyone have any ideas as to what might be wrong here?

Thanks!

So, the engine never stalls, right? (Engine is idling when you stop.)

What are the codes causing the CEL?

The next time this happens, try opening the gas cap and listen for a whoosh of air.
If your EVAP system isn’t allowing sufficient air to pass through the charcoal canister, your gas tank will form a vacuum in its air space as the gas is pumped out, making it difficult for the pump to maintain fuel pressure as the vacuum builds. Your stopping when the engine dies could be enough to allow enough air to get into the tank to relieve the vacuum. That would cause your symptoms.

The most common cause of this is “topping off” the gas tank, which in some cars can cause saturation of the charcoal bed with fluid gas. If you do this, I recommend you discontinue the practice. Repeated struggling by the fuel pump will cause premature failure.

This suggests that the engine is stalling.

Post the codes. My guess could be wrong.

There’s no way in telling what’s going on with your vehicle until it’s figured out why the Check Engine light is on.

There are some parts stores that’ll plug a code reader in and tell you what the generic code is that’s causing the Check Engine light.

But until that’s known?

It’s anybody’ s guess.

Tester

Reading out the diagnostic codes is the natural place a mechanic would start. I think you may have a problem with the alternator. Check the drive belt for wear and adjust the drive belt tension.