P0301 Cylinder 1 Misfire

[Precise1]

Ok, bought it 6 months ago. I replaced the plugs with NGK platinum, it ran fine for months with several 400 mile trips. A month ago with me driving it on a 7 mile commute, it would start to stumble only after I stopped at a store and restarted it warm. It runs fine from cold until you shut off and restart.

 

*I ignored it at first but when it became worse I replaced D cap/rotor/wires. No change.

*Put in Techron injector cleaner with a low tank and 10 gallons of Chevron gas. Have only burned a couple of gallons, no change.

*I determined it was not the spark plug by swapping #1 & 3 and pulling plug wires while it ran, all pointing to the #1 cylinder not the plug.

*#1 (and all others) have spark in the wire as tested with timing light today.

*Injectors 1 & 3 pass the resistance test (8 or 10-15 ohms IIRC)

*Timing is 12-13 BTDC and would be higher without the misfire.

 

2 weeks ago the neighbor plugged in his OBD2 scanner and gave me a P0301 code. Today I bought my own reader (why do I cheap out, I should have spent a little more for a better unit) and it showed P0301 #1 cyl misfire, P059 O2 circuit slow response, Bank #2 Sensor #2, P0158 O2 sensor circuit high voltage Bank #2 Sensor #2 and P0301 #1 cyl misfire.

I erased the codes, warmed up the motor, shut it off, restarted, for CEL and read the codes for two counts of P0301 #1 cyl misfire

 

Ok, I see I missed something in the FSM when I was trying to find the injector test specs so I'm going to go check the air intake, EGR and unplug injectors.

 

Anyone have any ideas, please let me know because I'm not getting any closer yet...

 

B

[Simon]

A friend with an Xterra had random cylinder misfires, and all it took was an injector flush to solve his problems. It's possible the injector is just gummed up.

[Precise1]

Well, it is not random, it is specifically cyl #1 but yes, that's what crossed my mind when i bought the injector cleaner even before Derek suggested I try that. No dice yet, and the 'only when hot' scenario has me wondering as well. Thanks though!!

 

I should probably change the fuel filter, seeing as it probably has never been done either...

 

B

[johnm]

It is a little weird, it almost has to be something specific to the #1 cylinder, right? The #2 O2 sensors don't affect fuel mixture for the ECU, that and the MAF, EGR, and other things that serve more than 1 cylinder would give you something other that just what you got. Fuel injector for #1 might be bad? Valve spring going bad so not getting compression every time? Piston rings? But would either of those only show up on warm restarts only?

[Precise1]

Yeah, I'm leaning towards the injector. When I trouble shoot after work again, I'll check the resistance (or whatever) both hot and cold, but that wouldn't show a mechanical clog, just an electrical failure.

 

It is a bit irritating. Either work right or break already!!

 

B

[5523Pathfinder]

B, I still think a injector flush would help.

 

 

As for your other codes, there is a few TSB's....NTB99-004b

 

IF YOU CONFIRM

If an applicable vehicle shows the MIL 'ON' and one or more of the following DTCs are stored in ECM:

 

96-97 MY Pathfinder vehicle: DTC P0130, P0150, P0136, or P0156.

98-00 MY Pathfinder vehicle: DTC P0131, P0134, P0138, P0140, P0151, P0154, P0158, P0160.

99-01 MY Frontier (V-6 Engine Only) or 00-01 MY Xterra (V-6 Engine Only) vehicle: DTC P0131, P0134, P0138, P0140, P0151, P0154, P0158, P0160.

02-04 MY Frontier (V-6 Engine Only), 02-04 MY Xterra (V-6 Engine Only)

DTC P1143, P0134, P0138, P1163, P0154, P1146, P1166, P0158.

 

ACTION

Use the Service Procedure in this bulletin to diagnose and repair the incident (if it should occur).

 

Perform a voltage drop test to check for a poor "ground " condition.

If necessary install a sub-harness between the intake manifold and the cylinder head to provide a direct path to "ground".

 

And......NTB01-048A to reprogramm the ECM...

 

If an applied vehicle has a MIL "On" with any of the following DTCs stored in the ECM:

 

· P0138 (Bank 1) H02S2 (Rear) (Max Voltage Monitoring)

· P0139 (Bank 1) H02S2 (Rear) (Response Monitoring)

· P0140 (Bank 1) H02S2 (Rear) (High Voltage)

· P0158 (Bank 2) H02S2 (Rear) (Max Voltage Monitoring)

· P0159 (Bank 2) H02S2 (Rear) (Response Monitoring)

· P0160 (Bank 2) H02S2 (Rear) (High Voltage)

 

There are two repair actions that may be required to resolve this incident:

 

1. Replace the incident bank(s) rear oxygen sensor(s) as indicated by the DTC on the CONSULT-II self-diagnosis printout to correct the condition.

 

2. Reprogram the vehicle's ECM to the New ECM Data P/N

[Precise1]

Well, either it gave up the ghost or I convinced it to fail. The resistance call out of the injectors is 10-14 ohms @ 75 degrees. I checked injectors 1 & 3 and got 34 ohms and 12 ohms. I started the vehicle (it ran rough), let it warm up,then sit for 10 minutes for everything to heat up and rechecked the injectors. Infinite resistance on injector #1 and 14 ohms for #3. For kicks I checked the wiring harness for proper voltage and no problems there.

 

The good news is that all vehicles with the NA VG33 use the same injectors so that gives you a pick of earlier R50s, some Fronties and Xterras to scavenge from.

The local PickNPull has a fresh 98 pathy and older 00 Xterra that will get a visit from me Saturday.

 

I have a question aboput injectors though, I see talk about blue or black marks or stripes in the description. I wasn't looking for this but didn't see anything like that; they are Nunya injectors, a lovely shade of pink. I'll look again when I get home.

 

Are these colors not to be mixed and matched for some reason? Is there some significant difference?

 

Thanks,

 

B

[Alkorahil]

I have a question aboput injectors though, I see talk about blue or black marks or stripes in the description. I wasn't looking for this but didn't see anything like that; they are Nunya injectors, a lovely shade of pink. I'll look again when I get home.

 

Are these colors not to be mixed and matched for some reason? Is there some significant difference?

 

Thanks,

 

B

 

Nissan injectors from back in this time period have a colored dot on the top of them. (blue, black, white, yellow, etc) All the injectors need to match on your engine. Os if you have say blue injectors you need to make sure the one you get is also blue.

If you are going to replace an injector please make sure to put new upper and lower O-ring gaskets on it as well.

[Alkorahil]

 

P0301 #1 cyl misfire, P059 O2 circuit slow response, Bank #2 Sensor #2, P0158 O2 sensor circuit high voltage Bank #2 Sensor #2

 

 

 

Given you tested the #1 injector I think you have two seperate issues. The B2#2 O2 sensor is kaput and the injector. The two are not related to each other.

[Precise1]

Thanks Rob, that's exactly what I needed to know. Too bad it slims down the chance of finding the right ones.

 

Yes, I have heard it advised to replace the o-rings but thanks for the reminder!!

 

B

[Precise1]

Alrighty, how to wrap this up?? In a nut shell, it cost me about $380 to fix and all I did was replace one injector and the fuel filter.

 

The resistance call out of the injectors is 10-14 ohms @ 75 degrees. I checked injectors 1 & 3 and got 34 ohms and 12 ohms. I started the vehicle (it ran rough), let it warm up,then sit for 10 minutes for everything to heat up and rechecked the injectors. Infinite resistance on injector #1 and 14 ohms for #3. For kicks I checked the wiring harness for proper voltage and no problems there.

 

On line I could find rebuilt injectors for $50 but they didn't specify the color code, so I wasn't going to use them. I found some Beck/Arnly injectors of the correct color (black for mine) for $95 new but I really didn't want 1 new and 5 old injectors (silly perhaps) so I bought a set of 6 used injectors along with the fuel rails from this place http://www.ninfiniti.com/ for $200 shipped to my door. Another $125 for a decent OBD2 reader (buy a $50 unit or a $300+ unit, don't waste money on a midgrade one) and another $50 for a full set of new seals and a fuel filter from RockAuto. The car runs like a champ, the best since we have owned it thanks to the full tune up.

 

The faulty injector was failing intermittently when hot, how annoying is that??

 

I now have spare black injectors with full seal kits that I'm willing to sell at a good price. PM me or check in the Classifieds, and Thank You to everyone who helped!!

 

B