My '87 300E has been running very rough lately. It starts right up, every time. However, it acts like it is not running in all cylinders. I notice the power is substantially weaker, and it sucks down gas like there is no tomorrow. It takes a quarter tank to drive 25 miles!! The gas econometer, when idle, stays in the middle. Acts as if I am flooring the gas pedal. The only time the meter goes down is when I am coasting or when sitting at a light, throw the car in neutral.

Most time the car acts like it is going to die when sitting at a light or stop, but it never does. It just coughs and sputters.

I suspect some kind of vacuum leak, or a badly needed tune up. I don't want to throw money in it unless I know at least it may help the problem. The car has a little over 300K on the clock.

If it is vacuum related, how do I know? Same question on the tune up. Is there a way to check if I need a tune up?

Anyone has any idea, or it ready for the heap yard?

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04 Infiniti G35.5 BS
10 X204