QuestionWell I decided to look at the plugs and one looks pretty oil fouled so I changed those out...drove it around till I got to operating temp and it seemed to smoothen out some.. A friend of mine pointed out that it sounds like theres and exhaust leak....could that also cause loss of power and the sputter?
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My Maxima has had a sputter for some time now. Fuel economy has gone to hell as well. The "check engine" light has never came on. I have changed the O2 sensor, fuel filter, and spark plugs, I have also went back to the old factory air box since I thought the K&N Style filter oil could be causing my MAF sensor to burn out. I'm wondering now if my fuel pump could be the problem. It always seems to run for about 5-10 after I shut off the ignition.
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John,
If you are talking aobut the fuel pump running after the ignition is shut off then replace the fuel pump relay. For my thoughts I would check the basics like timing and compression since the car is a 1993. If the timing is on and the plugs, coil and fuel pressure are in order I would looking at the throttle position sensor. But, we are just going through systems from the cheapest to the most costly. So, you have done the plugs, 02 sensor and now have the stock filter. Check the fuel pressure first. Then, the timing. Then, the compression and so on until you isolate the problem.
AnswerJohn,
Yes, the manifold bolts are known to break on your Maxima and the exhaust leak will cause the car to sputter since the oxygen sensor gets fooled by the air entering the exhaust. Get the car on a lift and check to see if you have any manifold bolts that have popped off. If so, replace them. The manifolds have to come off to get the broken bolts out.
