HELP! Problems with AUTO

[TopCatGr58]

Hey folks,

Sorry to bother ya'll, but I'm in need of some diagnostic assistance with my SUV. It's a 2004 Nissan Xterra with a 3.3L V-6. It has ~140k miles on the engine. I performed the timing belt change at ~100k along with new platinum spark plugs. I also do my own oil/filter changes and other stuff, but not much has been needed. I routinely put in Generic Injector cleaner, and use good quality gas...but it IS E-10. The last fuel I put in it was from a NEW KROGER station that had just been built/open a few months ago, so their tanks should have been clean!!

I drove the vehicle home Friday and when I arrived at home, it was idling roughly. It was on 1/4 tank....I fill it up on the weekend and run it all week long commuting to and from work, and so I know I can get whole week's worth without having to fill up until the next weekend. We did have a very cold spell the previous Wednesday where the temps got down into the teens, and I did drive it to work and back that day, as well as Thursday and this past Friday. SO...I was thinking that it might have gotten some water condensation in the tank even though it has NEVER done it before??

I got some RISLONE combo fuel treatment cleaner/gas dryer/water dispersant and put it in with a FULL tank of fuel on Saturday at my usual fuel place, NOT the Kroger. Saturday the Check Engine light started coming on and varied from blinking to steady on and back to blinking again.

It has a low rpm miss...very noticeable, but I can get it up to full rpm, so it's not running low/out of fuel...so I think I've ruled out clogged fuel filter or weak fuel pump. It's EFI. I drove it to work today, still behaving the same. Took it to the local Advance Auto for a Check Engine light check.....it just said that the #2 cylinder had a misfire detect: Error code P0302 and then of course the second error P0328 a Knock Sensor on the Circuit High Input Bank1....because of the misfire it's throwing the knock sensor!

So...now I'm fishing for ideas, either other diagnostics I can do...It's RAINING tonight, so it'll be tomorrow when I can look at it.

It has a single coil and distributor system, so it can't be the coil,but could be the cap/rotor...or the wire/plug cap.....or the plug fouled itself? Wondering if it could also be a failing fuel injector??

Thanks in advance!
T.C.

[GLoweVA]

With the new plugs, i'd suspect the insulation on the plug wires are breaking down.
Might think about replacing all of them.

[GLoweVA]

Btw, i traded the liberty in and got a 2015 exterra. NICE RIDE!

[motoman]

May wanna double check the plug reccomendations. Majority of newer vehicles having individual coil packs require the use of plugs from the stealer, specificly. Use of any other brand/type can and will damage coil packs....and they aren't cheap.

[DiverRay]

Put a scan tool on it and see what it says! They are a VERY helpful tool for the modern autos. You could have a bad injector/plug wire, and it may have taken out one of the O2 sensors. There are a few other sensors on that engine that like to go out as well. I have a friend with a 2002, and he's had to replace the cam sensors on it.
Good luck!

[TopCatGr58]

Hey George,

I was thinking about the wires, but like we've talked about with our bikes vs. cars, they are fairly secured/stable, and so they don't get much/any flexing, but yet I supposed the carbon fiber core can break down over the years and heat exposure.

Brant, I stated that this engine has only 1 coil, and uses a rotating distributor cap/rotor system, so I don't think the brand specific plug situation will apply since it doesn't use the coil on plug design, but I'll be pulling that plug and checking it out anyways.

Ray, what type of scan tool are you talking about? I took it to the auto parts store and had them use their error code checker, and the 2 errors I mentioned above were the only ones it showed....the misfire plug # and the knock sensor. Are you talking about a DEALERSHIP scan/computer analysis??

T.C.

[IanDMacDonald]

Hey TC- I got a little dirt under my nails with Xterras (just kidding, I wear gloves). First thing I'd do is go open the hood now and see if u can see any arcing. Second, those distributor rotor bearings go bad. Check for play in it.. Third, u could pull your plug to see if it's wet. If so, could be an intake leak, causing coolant to sneak-in.

[IanDMacDonald]

A dirty FI is possible I guess. Let's cross our fingers for an easy fix.

[ViperRon]

I know you would expect this to show as another error code but my experience with Oxygen sensors is they have never shown up in the error codes for me. Just show up as hard start very poor idle bad mileage and poor power. I do not know how many miles you have on yours but they do go bad and cause everything to be off. They tend to start failing with problems after carb cleaning or cold weather for me. If they recommend replacement in 50K and you have 90K on the sensor might be time for replacement. You may have 2 of them in your system I generally replace both at the same time.

The other issue I have seen is getting diesel fuel mixed with my gas once. I was not the only person that got nailed when the tank at the store was topped off with diesel instead of gas. You can usually smell it in the gas.

[Bikes]

Dont rule out a bad, new plug......

[trbig]

Autozone/Oreilly's or the like have readers that they plug into your vehicle (Usually right under the dash under the steering wheel) they can tell you what kind of code the engine light is coming on for and they do it for free. It'll usually help narrow things down a lot closer than a bunch of beer drinkers on a motorcycle website throwing out WAGs from their computers. Get those codes and you can look online to find the most probably culprit with that particular vehicle.

[TopCatGr58]

Hey again,

Thanks for the info. I did have it read at the auto store, and put the error codes in my FIRST POST, but they don't tell you when the injector goes bad, just things like MISFIRE and such...which is what I had. With all of the real MECHS on here, I was hoping for more than just WAG's with all of the history and diagnostics I had already done/had done!

I have done some more net searching and have found notes about the distributor bearings problem. I also found info about how to TEST the injectors by using a MM/Ohms....should be about 12 ohms....if much higher, ie. 17 or so....stuck closed....if much lower....stuck open.....or possibly fried. Just checked....they aren't CHEAP! And it's suggested to replace ALL of them at the same time.....due to extra work of having to remove the intake manifold to gain access....replace gaskets, etc.....but I don't have room in the budget right now for this....just put on $700 worth of tires a little over a month ago. So....if I replace 1 faulty injector(if that's the problem) then perhaps I'll get some time of full functionality before any other injectors go bad, so I'll have more time to get more $$ in the bank! Bills, bills, bills!

I'll let you all know what I find out as I persue this tomorrow!

T.C.

[Radioguylogs]

It would be easy to mist the plug wires with a spray bottle.

[DiverRay]

TC,
I ALWAYS replace wires and plugs at the same time on newer autos. The "new" wires seem to go bad when you don't. If you didn't put new wires on, that would be my FIRST repair. The knock sensor probably hit because of the misfire. I don't know what wires are for that, but they should be less than $100 for good ones. My ML320 has 2 plugs per on a V6, and the 3" long wires are $140 per set at the CHEAPEST place I can find....

[SFerinTEXAS]

plug off vacumn line to egr. If that system is the culprit it should run better just not efficient.