My Maxima was fine running fine this morning in city traffic stop and go, as soon as I get out on the expressway running at about 70 to 80 mph for about 20 minutes I get sputtering I been running 89 octane Sunoco. What is going on? I threaded before about this I thought the problem was resolved because It smoothed out in city traffic and I thought I was running a 91 octane after thinking back it is 89 octane. As you can see I am staring with the chepest solution and wooking my way up$$$$$$.

 

Premium fuel recommended: i.e. 91 or better. I only use 93, and only will.

 

For maximum performance use premium unleaded fuel only. That is what is says on the inside of the fuel door.

 

Like they said, only use 91+. A few times I have had bad tanks of gas, noticed some surging, then sputtering. I actually thought something was wrong with the car, but once I filled up again, it was back to normal.

BTW, all my bad gas experiences have been with BP.

 

thanks guys I got a bottle of chevron techron and I am running all of this 89 octane and doing 91 or better out I want to put some seafoam in I heard some good thing about it I tried autozone r and s straus and pep boys and they never heard of it Im from Philadelphia.

 

i had the same thing happen once at high speeds it would buck. turned out to be my fuel pump was going bad

 

how can i tell if it is the fuel pump or not

 

you have to put a gauge and test it at w.o.t which i believe is 43 psi. it took me a while to figure it out though. it first started off as bucking when i got up to the higher rpms but when it got cold i had problem starting till it wouldnt start anymore. t doesnt have to be the fuel pump but something related EX. fuel filter, injs. but the easiest test is the fuel pressure. does it only do it at w.o.t or at any speed.

 

Could also be a clogged fuel filter - but I'd expect that to starve the engine all the time at high speeds - not after 20 mins of driving - cheap to replace - especially if you are not sure when it was last changed.

 

C Max it runs fine up until I punch it then it will run like crap for a while then smoopth out as if nothing ever happened this has been happening for a week now

 

my guess would be the fuel filter or pump. more towards the pump if the fuel filter was clogged it would do it more often than at w.o.t. the fuel pump will run you about 90 bucks the walbro GSS342 which is the 190hlp. the cheapest thing would be to change the fule filter and if you have access test the pressure while your at it.

 

Just so you know, I've ran 87 octane in my car for a few weeks (premium was a waste since car was running rich) and I did not have any problems at high speeds. It's probably just bad gas or fuel pump/filter/injector related as mentioned above.

 

Thanks guys Im going to change the fuel filter first is it hard to get too?. What is the procedure. I dont want what happened to me before on my 87 max when I changed it I took one line off and it sprayed me pretty good. Im also just going to run all this 89 octane out just for good measure,isnt it strange how long it takes to burn a tank off when you are purposely trying to do it,geez it is taking forever.

 

Read the stickies at the top of forum... all the instructions you need are there.

 

the filter is on the firewall and pretty easy if you use a long screwdriver to pry off the hose. start the car and go to the fuse panel, pull out the fuel pump fuse and wait till the car shuts off. then try and start it this will relieve the fuel pressure. after you put the filter in put the fuse back in and start the car.

 

i dont think the problem is fuel related, ive ran 89 for quite some time and i got no bucking, didnt even feel any hesitation or knocking. it could be its fuel starved, fuel filter might need changing. would a bad ECTS cause bucking at highway speeds?

 

I looked at my fuel filter It look like it is the original one all rusty looking Im going to change it.