Repair Topics / Engine Intake Manifold

• How to check for a engine vacuum leak
• Howling noise from car

Question: 2002 GMC Jimmy, miles: 67,000. I've read that the GMC Jimmy's are sort of prone to getting carbon build-up in the intake manifold. Is there any kind of carbon cleaner or cleaners that you could recommend that I could use to spray into the throttle body to clean it out, without harming the other components? I'm kind of new to having a fuel-injected truck. I've always had a carburetor in my cars. When I wanted to clean out the crud, I would just spray carburetor cleaner down the carburetor and that would take care of all the build up. But, with an injected vehicle, I feel a little lost. The problem that I've been having is that I keep getting carbon pieces flaking off and getting trapped in the EGR valve.

Answer: The intake manifold should be removed to properly clean the carbon buildup from the inside of the manifold. On engines with high mileage that are starting to use oil, the oil causes a carbon buildup to occur at an accelerated rate.

Question: 2003 Honda Accord mileage: 28,000. Hello, my car has a poor running problem at idle, It sounds like it has a whistle. When I rev the motor I can hear it kind of go away. But it is still there. what should I do ?

Answer: Its sounds like you have a intake manifold gasket that is leaking, Remove the manifold to replace the gasket. Your problem should go away.

Question: 2004 Ford F-150 mileage: 84,000. Truck runs good but when the engine comes down to idle it starts running funny. I can hear a vacuum leak so I don't think it is a vacuum problem what should I do?. How do I test this?

Answer:  Thank you for asking this question for it is one that send people down the wrong repair road. Some vacuum leaks you can not hear, you need to test for leak by physically checking all vacuum hoses. If all hoses test ok suspect the mass air flow sensor for your problem.

Repair Topics / Engine Intake Manifold

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