Engine miss when Warm

[sm6989]

I have an 01 maxima, lately when I drive it, It drives perfect when you first start it but drive it for about 5 mins it starts to act sluggish and has a miss. I had a overheating problem since my radiator was leaking, replaced that, transmission fluid and plugs since it got alil hot the one day. But now has that miss, it started running like that when it got alittle on the hot side when driving it one day(not too hot though, I know better to turn it off when its getting up there) Now the overheating problem is gone it just has that miss after about 5-10 mins of driving, any ideas what it could be?

[allensteiner]

k...so you know that you have a misfire but you don't know what causes them??? how do you know it misses? with a misfire you're most likely to get a cel - is it on? i bet you have a different problem but first answer these q's and we'll go from there.

[sm6989]

Just know how it feels/sounds when a miss occurs lol, the car yesterday was fine for a bit, then started sounding like the exhaust was backfireing after 4k if you got on it and was hesitateing..Turned the car off, started it back up then start running with that miss again. there is a CEL light on which is from my 02 sensor awhile back, so dont know anything else is throwing a code yet.

[nj1sh]

I believe the o2 sensors are disabled when the engine is cold in the first few minutes. When it gets warm the o2's kick in. If you have a faulty o2 sensor the mixture is not right and it causes misfires. I know my car does it too due to one of the o2 sensors that is not working right. I noticed the car runs very sluggish after 5 minutes.

[sm6989]

Its been throwing that code for about a year now, so think it just finally kicked and went tottally bad? If I unplug it would it be any better?

I guess it could be that though cause when it was missing the other day you could smell how rich it was burning.
Modified by sm6989 at 9:10 AM 7/25/2008

[allensteiner]

reset the ecu - that'll clear the code and should make things better till it comes back. and replace the o2's - it's killing your mpg as well.

[NutriaforBreakfast]

You could check the coils with a multimeter to make sure they areok and change the plugs-Haynes or the FSM has a good procedurefor that

If they are ok you might try try the camshaft and crankshaft positionsensor and see if they are ok too.

I would consider cleaning the throttle body and Idle Air control valve

Sounds like except for the miss the car has a lot of power.

[sm6989]

Ive changed the plugs and cleaned the TB, I'll check the coils, how should I test the sensors? just with a ohm meter?

[MCovington]

Check the coils. I had the same thing drive me crazy on a 95 Maxima. I found a back coil was bad. It would be fine until the car warmed up and then I would feel a slight skip or miss, only under a load though.