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Dave Nova
Dave Nova, Oldsmobile Tech
Category: Oldsmobile
Satisfied Customers: 19452
Experience:  ASE Master Certification. GM World Class Certification
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Oldsmobile Bravada: 99 bravada starts put runs rough with little

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99 bravada starts put runs rough with little power, but after about 30 seconds of idle will drive fine unless you mash down the gas pedal will almost die out. Codes say lean both banks and a couple others. Any ideas of what this might be? I've been driving it for a year like this.
Hello and thank you for trusting me with your question. My name is XXXXX XXXXX I will do my best to help you with your Oldsmobile problem.

Having the engine stall out when accelerating, along with having lean codes are classic symptoms of low fuel pressure due to a weak fuel pump. Connect a fuel pressure gauge to the test port on the engine to check fuel pressure. You should have 60-66 psi fuel pressure with the key on, engine off. If the fuel pressure is lower than specified, replace the fuel pump. This is a common failure on these trucks.

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Customer: replied 5 years ago.
Can't be fuel pump. Its been going on for years like that. Any other ideas
If not low fuel pressure then the problem could be due to vacuum leaks or a bad mass airflow sensor.
Customer: replied 5 years ago.

Checked mass air flow sensor. How would I find if its a vacuum leak and where it is?

With the engine running spray carburetor cleaner around the perimeter of the intake manifold. If idle changes then you have found a leak.