Recently I bought a new 99 Maxima (wrecked the last one ) and about a week after buying it the cel comes on for the O2 sensor (front one) and i replace it. About a week later i start to notice a hesitatoin at low rpms - like if i try to accelerate in a high gear while going kinda slow it stumbles a bit. I'm not sure what it could be but i was thinking it might be something to do wiht the fuel system. Let me know what you think.

thanx
-matt

 

no ideas???
i'm going to try some fuel injector cleaner

 

I had something similar recently, and it was found to be a loose pin in the connector going to the MAF. When the car accelerated, and the engined moved about the mounts, one of the pins would slightly lose contact because the hole was enlarged on the connector. When I let off the gas, I guess it made contact again. It felt like a hesitation, and it even did this at cruise when applying throttle. I don't know if this is common, but maybe an avenue to explore.

The connector was repaired, and all pins fit snuggly...no more problems!

 

no no no no no, I had the same thing happen to mine TWICE! I swear, exactly the symptoms you describe.


it is one of your coil packs (aka ignition coil) going bad. END OF STORY.

p.s. trust me on this one!

 

crap - i've heard that costs a ton. Time to do some searching...

thanx for the help.

PS - is there some place that can conferm this and tell me which one? I would have thought it would through an engine code.

 

ignition packs, what does that entail, because i have this same problem,,,

 

they are like individual coils - one for each cyl. When you change your spark plugs it is that little box with an extention and a plug on the end that you have to pull out to get to the spark plugs themselves. Its kinda like short sparkplug wire with a box on the end. But its not cheap...

 

you can tell which one is bad - just go to a local mechanic or dealer and ask them to ONLY test each coil with a kind of multimeter device.

Or, do as I did...drive hard for a while, I mean WOT often. Eventually this will lead to the bad coil pack deteriorating to a point where it misfires severely, and with it the cylinder under it. Once that happens, you got it made because it'll throw a check engine with a "cylinder X misfire" code. Then, you know coil X is bad and you must replace it. Best of luck!

 

Do you have a CEL? If you do, then it is most likely a coil problem. If there is no CEL, then have the connector going to the MAF checked. It only takes a couple min. by using a test pin and checking all the holes to make sure there is a tight fit. If one hole is loose, you found the problem, if not, then more troubleshooting. It could be the harness somewhere.

 

thanx - i have no cel. I will check the harness first but i don't have a "test pin"