Q: Rough when accelerating sluggish

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My 2.0 Tubo runs very rough when accelerating and doesn’t have much power. The problem started without warning. I didn’t get any warning lights or codes on my dashboard. I have changed all the old vacuum hoses, connections, and inter hose units. The car ran OK for 10- 15 minutes. Then it got very sluggish again. It idles very smooth. But when I rev to about 2500-3000 it starts to get sluggish and runs very rough but coming down to an idle its runs very smooth. Do you have any ideas on how to fix my car?

A: Hello. One of the first things that I recom...

Hello. One of the first things that I recommend checking is the fuel pressure. Have a technician check the fuel pressure on the vehicle to ensure it receives the proper amount of fuel as the the gas pedal is depressed.

If not, you may have a fuel delivery issue such as a weak pump or leaking fuel line. I also suggest checking the catalytic converter for clogging.

The sluggish performance you are experiencing could also be due to an ignition module, crank position sensor, or throttle position sensor becoming faulty when warm.

Finally, there has been some cases where the intake manifold gasket becomes warm, and has started to leak. There's a wide variety of issues, which can cause these symptoms, so I suggest that a technician look at the vehicle firsthand to determine why the engine is running rough.

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