Hi all, so I have a 2000 Maxima SE I bought used 2 years ago. I live in Phoenix. Back story: car ran fine first summer, but once winter hit and temps dropped, the car would have hard time starting/staying on in the morning unless I kept revving it up until it got warm. Then it would run fine all day. Dealer did a inspection and determined my MAF was faulty. I replaced it, but problem still continued. I just kept driving since it would run fine once warm. I eventually changed the spark plugs, water pump, thermostat, and radiator. Car kept running same (just issues in cold starts/cold mornings) up until Oct. 2014. I had the car parked for a week and when I went to turn it on, it wouldn't turn on. I replaced the battery, and the code it gave was P0335 (I think) it was for the rear crankshaft position sensor so I replaced that as well. The car turned on but started sputtering a lot and giving backfires while I tried revving it. So I now changed the fuel pump. The car still starts fine but it will not accelerate at all. When I do try to accelerate, it immediately start sputtering and backfiring. I think it might be a timing issue, but not sure. Any advice is helpful.

 

Hard starting in cooler weather could be a bad ECTS (Engine Coolant Temperature Sensor). If the sensor is reporting a higher temperature that actuality, you get a lean fuel mixture. This is the opposite of what a cold engine needs.

Find someone with an OBD code reader that will show engine temperature. Hook it up in the morning when the car is cold and see what temperature is being reported. It is not necessary to start the car for this, just turn the ignition on.

 

I actually changed that sensor as well, I forgot to mention. That was actually the first sensor I replace, then the MAF. Was I supposed to reprogram the ECM or something when I switched those out?

 

Re-programming of the ECU is not needed for those. In fact, you can replace pretty much everything with out needing to re-program.

Was the MAF a Nissan MAF or local parts store? People have lots of problems with non-Nissan MAFs.

 

No it was from auto zone. I bought the first one, it had a 1 year warranty. I didn't look into nissan if they had one, how much etc.

 

I bet that's your issue. I tried non-OEM MAFs in the past and they crap out. Go with OEM. Shop around. I found courtesyparts.com to have the best price and I knew it would be OEM. $77.69 + shipping right now.

A bad MAF won't always throw a code.

Disconnect the battery so the ECU can reset when you install. No reflash is necessary, but it is recommended.

 

+1 !
Absolutely correct - all three suggestions.

 

Thanks for the suggestions everyone. I replaced the cam shaft position sensor, and my car was able to accelerate with no problem yesterday afternoon and this morning. Even took the car on a small cruise around Phoenix last night! Only issue was this morning. I left the car parked in the driveway, exposed to the cooler weather, and this morning when I tried turning it on, it wouldn't stay on unless I kept revving it over 1000 rpm until it got warm. (Needle at half way point) after that the car ran fine. This has been the most consistent issue with the car since I got it. Any thoughts on what is causing the the car to start this way on cold starts?

 

Since you already replaced your ECTS, your IACV is the next suspect. However, I suggest checking your codes (and "incomplete" meters) first.

 

Hmmm... If you already changed the coolant temp sensor, I would second the IACV as being the culprit.

Another possibility is the TPS (throttle position sensor). IIRC, the TPS controls the engine when it is cold and then an O2 sensor takes over after it is warmed up.

I remember reading somewhere on here that a bad manifold gasket was the origin of these problems. Apparently, before the engine warmed up, there was a slight leak and cool air was getting in the manifold causing stalling issues, but after the engine was warmed up, the gasket expanded and sealed it off.

A new gasket is definitely cheaper than a new IAC valve!

 

Car's been neglected and needs a good cleaning. Follow the 60k mile service. New spark plugs and clean the iacv which yes means you take if off and clean the inside. A 5 year old could do it. Try some premium fuel from a nice station too.