# 94 altima GXE poor mileage



## rickjp (Nov 22, 2004)

hello, this is my first post. I'm really looking forward to getting some good advice here and also hopefully being able to provide some as well. Anyway, my current problem is with my '94 GXE which has about 150,000 miles on it. I seem to be only getting about, in my estimation, 15 miles to the gallon. This seems hard for me to believe that any 4 cyl. engine could be that bad. I just replaced the fuel filter but I don't really expect that to improve much. Does anyone have any ideas on why the mileage would be so bad? Anything I can start to check? Thanks for any help.


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## lshadoff (Nov 26, 2002)

rickjp said:


> hello, this is my first post. I'm really looking forward to getting some good advice here and also hopefully being able to provide some as well. Anyway, my current problem is with my '94 GXE which has about 150,000 miles on it. I seem to be only getting about, in my estimation, 15 miles to the gallon. This seems hard for me to believe that any 4 cyl. engine could be that bad. I just replaced the fuel filter but I don't really expect that to improve much. Does anyone have any ideas on why the mileage would be so bad? Anything I can start to check? Thanks for any help.


A tune-up is a good start. If the spark plugs, distributor cap, rotor, and spark plug wires have not been replaced recently, at least examine them all. Check the ignition timing. Examine all the vacuum hoses for cracks. If the car is running cold due to a faulty thermostat, the mileage will suffer.

In a poorly running car, the spark plugs can be of great help in diagnosing the problem. If they are black and sooty, the car is running rich, and the most likely culprit is the oxygen sensor. If they are worn (big gap) replace them. If one of them is different from the others, it could be due to a faulty injector or spark plug wire.

Just a few ideas.

Lew


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## Eddie57 (Nov 14, 2004)

rickjp said:


> hello, this is my first post. I'm really looking forward to getting some good advice here and also hopefully being able to provide some as well. Anyway, my current problem is with my '94 GXE which has about 150,000 miles on it. I seem to be only getting about, in my estimation, 15 miles to the gallon. This seems hard for me to believe that any 4 cyl. engine could be that bad. I just replaced the fuel filter but I don't really expect that to improve much. Does anyone have any ideas on why the mileage would be so bad? Anything I can start to check? Thanks for any help.


hey rickjp,

Make sure to keep your car is properly tuned up. Including new wiring, rotor and distributor cap. Don’t forget to replace the PVC valve. Also, have you changed the air filter? If it’s dirty and clogged that will kill your fuel efficiency.

Do not drive not aggressively. Jackrabbit starts and stops will kill gas efficiency. You’ll lose up to 35 percent on fuel efficiency with these habits. 

Keep you speed limit at 55-60 miles per hours. Anything about 60 mph wastes a lot of gas. 

Don’t let your car idle for too long. Turn it off if you’re going to idle for more that one minute. 

Using cruise control on the highway helps you maintain a constant speed and will save gas.

Make sure to have your overdrive on at all times. 

Maintain the proper air pressure (32psi). Under inflated tires don’t roll as well as properly inflated tires. Always have your tires balanced and your car aligned.

Use the proper oil for your car, probably 5w-30. Using the wrong oil will cost you miles. Make sure to change it every 3k miles or 3 months. Filter too.

Remove any items in you car that add weight. Tool boxes, bikes, any unnecessary items. The lighter your car is the more efficient it becomes. 

You might want to check your catalytic converter. Sometimes they get clogged up. 

Plan your driving. Don’t make more trips than necessary. Make all your errands on the same trip
Use the internet to you advantage. Make payments online or have automatic draft payments from your checking. 

Anticipate traffic lights. Every stop costs you money, not to mention the wear on your brakes.

Carpool is you can. This will cut you gas bill in half.

Drive with the windows up. There is more resistance when you have you windows down. 

There are many tips on the web, just do a search for improving you car’s gas mileage. 

My car is well maintained and I get 18-20 mp gallon in the city and 30 mp gallon on long trips. I have a 1996 Nissan Altima.

GL
Eddie


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## rickjp (Nov 22, 2004)

*94 Altima poor mileage*

Thanks, I have heard that the O2 sensor can be a big contributor to poor mileage. Are there any tests I can run in addition to inspecting the spark plugs? Would the ECU codes reveal anything even though the check engine light is not lit? The car actually runs very smoothly however, sometimes it hesitates on take off from stop almost like the old cars did that had a bad acceleration pump on the carb engines. And occasionally the car will stall out completely when you first start it but then runs fine after I restart it. This only happens now and then. 

Thanks for your help. :cheers: 





lshadoff said:


> A tune-up is a good start. If the spark plugs, distributor cap, rotor, and spark plug wires have not been replaced recently, at least examine them all. Check the ignition timing. Examine all the vacuum hoses for cracks. If the car is running cold due to a faulty thermostat, the mileage will suffer.
> 
> In a poorly running car, the spark plugs can be of great help in diagnosing the problem. If they are black and sooty, the car is running rich, and the most likely culprit is the oxygen sensor. If they are worn (big gap) replace them. If one of them is different from the others, it could be due to a faulty injector or spark plug wire.
> 
> ...


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## brewmeister (Aug 27, 2004)

I had this as well and started to lose power...in my case the primary catalytic converter was plugged and needed to be replaced. very expensive.

I now get amazing mileage and plenty of power.

as a side note, the back pressure blew the egr hose and I started hearing a hissing noise as well and smelling exhaust.


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## Kindfiend (Oct 13, 2004)

lshadoff said:


> A tune-up is a good start. If the spark plugs, distributor cap, rotor, and spark plug wires have not been replaced recently, at least examine them all. Check the ignition timing. Examine all the vacuum hoses for cracks. If the car is running cold due to a faulty thermostat, the mileage will suffer.
> 
> In a poorly running car, the spark plugs can be of great help in diagnosing the problem. If they are black and sooty, the car is running rich, and the most likely culprit is the oxygen sensor. If they are worn (big gap) replace them. If one of them is different from the others, it could be due to a faulty injector or spark plug wire.
> 
> ...


Sorry to revive this thread, but I gotta ask something.

Lew, I'm curious about something on my car and you seem to be very knowledgable about Nissans. My car has been running kinda poor lately. When I push on the gas and let go, the rpms will drop and then will rev to about 1500 (It goes higher the harder I initially pushed on the gas) and then kind bounce back down to 675. It has a ra-ra-ra sound when I start it up, which goes away after it warms up. The idle bounces a bit during this sound. The car will also bog down in all the gears, but does it intermittenly, mainly if I push the accelerator harder. It seems to bog the most after shifting into 4th and 5th gear. Gas milage is about 37 hwy. I've done the tune-up, all oem, properly gapped plugs, new wires, cap, rotor, front O2 sensor, and pcv valve. The chains and tensioners were replaced along the head gasket, water pump, and thermostat. I've cleaned the throttle body and IACV. The air filter is clean, and all emissions hoses are connected and snug. The EGR moves well enough, but I haven't cleaned that. MAF is functioning properly, and the TPS is set to specs. Compression checked out as well, even 185 across the cylinders. Timing is set at 13*, running on 93. The car has about 126,000 mi. on the clock, although I suspect it was abused; I know it was in an accident, but not how bad. It doesn't leak any oil, though I do have a small coolant leak at one hose going to the throttle body (to be fixed tomorrow). I did notice a very small amount of oil behind the distributor, but that is also rebuilt. I removed the dist. today and cleaned where it goes into the valve cover and reset the timing. There was no change in the way it ran.
Ok... I hope that's enough info on the car to help me out. :thumbup: 

Now, I haven't checked the cat, and the exhaust smells like it's running rich.
There is a small leak in the exhaust somewhere after the cat (I only have one). Also, I haven't replaced the rear O2 sensor, but I was under the impression it was more for diagnostics and affecting how the car ran. So I guess I'm looking for something else to check since I can't stand knowing I have a good car, but not feeling it at the moment.

Thanks. BTW, this isn't only to Lew, I welcome all suggestions


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