95 Maxima w/ codes

[lucasjsr]

I bought this car with 154K miles. I replaced the 1/2 shafts, brakes and rotors, fuel filter, spark plugs plugs check the ignition coils at each plug (I think they are OK) air filter is good. I finally broke down and took it to the Nissan Dealer in Hilliard Ohio. They found a bad injector in #4 and replaced it and the coolant temp sensor. They said I also needed an O2 sensor in bank 2 which they said was the one on the front of the engine). I purchased the sensor and it is in such a hard to reach place a local garage is going to replace it for me tomorrow. I could not even get a tool to get turn the socket once I managed to get it on the sensor. I took my car to Advance Auto and they pulled the following codes: P0150 I believe this is the front O2 sensor P0325 Knock Sensor (is this a problem? Should I check it after I get the miss firing fixed? Will the KS set a code by itself?) P0303 Cylinder 3 Misfire detected. I checked the spark plug and it had carbon and white powder looking stuff on the electrode after only about 300 miles of miles of driving. I checked and the plug is getting fire to it. P0155 O2 Sensor heater circuit malfunction (will replacing the O2 sensor fix this?

This morning it was about 17 degrees out and the car ran great until the engine started to warm up then it started running rough again.

The car had set unused for quite sometime. The previous owner was a new car manager at the local Lexus dealer and did not drive the car as he had a company car (I think he only used the Maxima to party and when stuff broke just drove it anyway. I was wondering it the fuel system might just have bad gas I am on my second tank and there is showing no improvement. I did add some injector cleaner to the fuel just on a crap shoot in case it might help. Any input (helpful) would be appreciated. I am getting quite a bit of time and money in this car and really love Nissan so I do not want to quit now.

If it does need an injector I think I will replace the other 5 to avoid future problems. Is there a site I can get the instructions to remove the intake manifold to reach the injectors?

Thank you very much.


Modified by lucasjsr at 7:53 PM 1/14/2008

[driftingmy240sx]

sounds like a coil is going bad on cylinder 3, but it is possible that it is another injector. knock sensors go bad on those cars. sounds like both o2 codes are for the same sensor and replaceing the sensor should fix that problem.

[Dracolove]

I have a 95 maxima also and the knock sensor is typically a ghost fix the other problems first have the codes cleared and if it comes up again the check it. I had it come up on me when both of my temp sensors went out.

[lucasjsr]

I replaced the O2 sensor and had the light cleared. It still idled and ran rough (below roughy 3000 rpm). The light blinked several, maybe 10 times then, came on for a while then, went off again and the engine seems to have smoothed out a bit. I will see what happens in the next few days. Since the car sat for most of the last 2 years and has 154K miles, would you recommend having the fuel injectors cleaned as well as replacing the KS? Thank you

[lucasjsr]

Thanks for everyones help and advise I'll keep working on this and let you know.

[OldmanPurdy]

The knock sensor showing up in codes can be caused by misfires so it seems all those codes are related to one problem.

[lucasjsr]

Are you reommending I get everythig running right then go after the KS or can the KS cause the problems?

[driftingmy240sx]

the knock sensor code only sets if the ecu sees a short or open circuit. a fuel injection service would not hurt. are you still running the stale gas that was in the tank, or have you since refilled with fresh gas? stale gas can cause a poor idle. when the check engine light flashes it means there is a fault detected that can damage the catalytic converter.

[lucasjsr]

Now it is running good except after I accelerate it hard and stop it will seem to misfire for about 30 seconds. If I take out of gear and let it idle it smooths out. After light to normal acceleration there is no problem now. Only after I stop after full acceleration. THere is no check engine light flashing or coming on at all. I am on the second fill up and use injector cleaner with each fill up. The car starts and runs good except for the stumbling after hard acceleration. Almost seems like the car is heeling itself, very strange and perplexing.

[3Q Jay]

cobwebs. most fi 'cleaner' is lame. use BG44K. best to run on 15 gal, and then change oil after. lotsa WOT flogging (but only if the oil in there now is in good shape (i wouldn't do that to an engine with 3 year 10k oil).

you may still have bad #3 coil, but likely the bad O2 was also triggering cyl misfire code. ks are not triggered by misfires, but bad ones can be a sign of an overheat. they are likely just hairline cracked at 154k, but that will do it. they are medium priority affect your low-mid range torque.

edit: i keep saying ks as in plural cause of my vh engines, but your engine has 1.

[lucasjsr]

I replaced tth O2 sensor and added the FI cleaner you suggested. It drove fine for a while now is missing again in #3. I have not had time to drive will run it tonight to see if the problems cleans up. #3 does have good spark and new Spark plugThank you

[NM50]

Check the resistance of the injectors.I believe 2.2 ohms is the specified value.If the resistance is normal the use a noid light to see if the pulse duration from the ECM is correct.

[lucasjsr]

Anyway to check the injectors for resistance with out pulling the manifold? If I have to pull the maifold I may as well change the fuel injectors whil I am in there. Injectors for my car are cheap enough on Ebay to justify replacing them rather than go through the extra trouble in the future. The BG44K seems to have helped, no more check engine light just rough idle and poor gas mileage now. It starts and runs great above 2500 RPM but seems to miss and lugs/misses/hesitates when crusing below 2500 RPM. I ckecked the KS and am getting a reading of 1,126,000 ohms. Specs on the site say 550,000 to 620,000 ohms. Could the Knock Sensor be bad?
Modified by lucasjsr at 5:27 PM 1/27/2008