Nissan Pathfinder Stumbles

[mscher]

Hey,

Our 98' pathfinder (3.5 v6 - m/t) with 115K mi, has ran like a champ until recently.

Often, though not always, it will stumble during acceleration, but will smooth out when up to speed. Plugs and wires were replaced in the spring.

Could be bad gas (lot's of ethanol out there), but we don't always buy at the same place?

It has never been to a repair garage, so is there something they can test for that may determine a cause?

Anything else that I can look for? I'm not getting any code errors.

thanks

 

[i386]

Re: Nissan Pathfinder Stumbles

Fuel filter is the first thing that comes to mind.

 

[ob]

Re: Nissan Pathfinder Stumbles

My 97' did the same thing at 65,000 miles.Turned out to be the throttle position sensor.I had no check engine light either.I recommend having it diagnosed by a competent dealer tech to narrow down which component is possible culprit.

 

[dolluper]

Re: Nissan Pathfinder Stumbles

With no codes your back to basics>>>fuel,ignition,grounds or green connections also make sure your charging system is up and running right very important with computer controlled vehicles.Does your problem happen on a cold vehicle or after it has reached operating temperature?????

 

[JRJ]

Re: Nissan Pathfinder Stumbles

Fuel filter is the first thing that comes to mind.

Fuel filter change was regular maintenance on our 97 Maxima. Good luck.

 

[KM2]

Re: Nissan Pathfinder Stumbles

The ethanol has nothing to do with your problem, so start looking somewhere else.

 

[mscher]

Re: Nissan Pathfinder Stumbles

With no codes your back to basics>>>fuel,ignition,grounds or green connections also make sure your charging system is up and running right very important with computer controlled vehicles.Does your problem happen on a cold vehicle or after it has reached operating temperature?????

Seems to happen warm or cold.

I'll try the fuel filter next.

 

[dolluper]

Re: Nissan Pathfinder Stumbles

In that case try a fuel filter {cheap easy} maybe do a fuel pressure test after,also check your MAF {mass air flow sensor},simple test is with the engine running tap the sensor with the wooden end of a hammer, the vehicle will stumble if working right.might take a couple of taps. It;s located in your air duct work for breather,also make sure your air filter is not plugged

 

[Windykid]

Re: Nissan Pathfinder Stumbles

I would check the fuel filter first. But a drop of 1-2psi can cause a chug, surge or stumble at various RPM. So do a fuel preasure test.

 

[LubeDude]

Re: Nissan Pathfinder Stumbles

All the above things are good advice, but you mentioned changing the sparkplugs! Did you use the same ones that were there already, or did you use something different. Just for example, some engines just do not like the new platinum plugs.

 

[mscher]

Re: Nissan Pathfinder Stumbles

All the above things are good advice, but you mentioned changing the sparkplugs! Did you use the same ones that were there already, or did you use something different. Just for example, some engines just do not like the new platinum plugs.

I did install Bosch platinums, but they are the same as the second set. I think the originals were ND's.

 

[Windykid]

Re: Nissan Pathfinder Stumbles

What have you done so far?

 

[LubeDude]

Re: Nissan Pathfinder Stumbles

I did install Bosch platinums, but they are the same as the second set. I think the originals were ND's.

Meaning that you replaced the set that was in there with the exact thing that was in it before??

I had a 87 4 cyl Toyota 4X4 that loved them, (Bosch Platinums) But my 6 cyl 4 LTR 4X4 Ranger hated them.

 

[orion25]

Re: Nissan Pathfinder Stumbles

The throttle body could be dirty. Get some cleaner and read the directions on the can. The TPS and MAF could be the problem as well. The way it sounds your problem is either fuel or air and the fuel was covered in the previous posts about the filter. Also, replace your PCV valve. They are cheap and can sometimes cause problems.

 

[i386]

Re: Nissan Pathfinder Stumbles

whatever happened with this one?

 

[MikDee]

Re: Nissan Pathfinder Stumbles

Keep it simple, First thing I'd check is the air filter, then the fuel filter, at 115k miles when were they changed last?