Hard starting with '02 Maxima after battery drain

[novasource]

I have an '02 Maxima. Consistently ran and started fine until I changed the battery a month ago. Since then:

*In normal Dallas summer weather (hot), starts fine on cold starts, but on hot starts RPMs will rapidly fall to 0 unless I nudge the accelerator to keep the RPMs over 1200 for at least 2 seconds.

*Today was the first day of fall-ish weather. Temps were in the mid-60s in the morning. Upon start, the vehicle ran very rough and died. Same with second start. I feared a mechanical problem. On third start, I nudged the accelerator and kept it running. After a couple of seconds at 1,500 RPM, I let off and it fell to normal-ish cold start RPMs. Driving off, I felt it hesitate off a stop a couple of times. I also may have heard intake backfires when accelerating from stops, but if so, it wasn't like a hard carburetor backfire I experienced on old GM products.

I am confused: what about a battery swap would cause this? I had the battery off for about 4 hours.

No SES light.

I understand that there is an adaptive idle relearn that may not have happened correctly, but does that explain the rough cold starting and possible backfires?

What should I check?

[Calvin3z]

To be honest this sounds like an injector problem. I know that a dead battery or replacement battery shouldn't "cause" this problem.

The reason I say this is that the symptoms you are describing are almost exactly what I was experiencing with my 300ZX TT. I took it to the dealer and they ran the ConZult on it and told me 2 injectors were not responding. Meaning that sometimes they were working and sometimes they weren't.

I hope that I am wrong about this honestly. Not sure if OBDII checks injectors or not. If you know it does it may be worth a trip to AutoZone to have them pull the codes.

[novasource]

To be honest this sounds like an injector problem. I know that a dead battery or replacement battery shouldn't "cause" this problem.

The reason I say this is that the symptoms you are describing are almost exactly what I was experiencing with my 300ZX TT. I took it to the dealer and they ran the ConZult on it and told me 2 injectors were not responding. Meaning that sometimes they were working and sometimes they weren't.

I hope that I am wrong about this honestly. Not sure if OBDII checks injectors or not. If you know it does it may be worth a trip to AutoZone to have them pull the codes.

Your 300ZX was a '95, right? Did its OBDI catch the injections?

Are dealers the only places that can diagnose this stuff? The only two near me have mediocre reputations.

[Calvin3z]

You are correct it was a '95. The Z had it's own connection interface to something called a ConZult that was Z specific as far as I know. I don't know if the OBDI would catch the injectors. But since you have an '02 I think it is likely that the OBDII might check injector response.

[Calvin3z]

I did a little poking around and found these codes for OBDIII can't vouch for accuracy. I got them from the following site.http://www.obd-codes.com/trouble_codes/

DTC Codes - P0200-P0299 – Fuel and Air Metering (Injector Circuit)

* P0200 Injector Circuit Malfunction * P0201 Injector Circuit Malfunction - Cylinder 1 * P0202 Injector Circuit Malfunction - Cylinder 2 * P0203 Injector Circuit Malfunction - Cylinder 3 * P0204 Injector Circuit Malfunction - Cylinder 4 * P0205 Injector Circuit Malfunction - Cylinder 5 * P0206 Injector Circuit Malfunction - Cylinder 6 * P0207 Injector Circuit Malfunction - Cylinder 7 * P0208 Injector Circuit Malfunction - Cylinder 8 * P0209 Injector Circuit Malfunction - Cylinder 9 * P0210 Injector Circuit Malfunction - Cylinder 10 * P0211 Injector Circuit Malfunction - Cylinder 11 * P0212 Injector Circuit Malfunction - Cylinder 12 * P0213 Cold Start Injector 1 Malfunction * P0214 Cold Start Injector 2 Malfunction * P0215 Engine Shutoff Solenoid Malfunction * P0216 Injection Timing Control Circuit Malfunction

[novasource]

Thanks. I probably should just drive it by AutoZone and see what their tool finds.

[NutriaforBreakfast]

Sounds like the Mass Airflow Sensor

[NutriaforBreakfast]

I think the MAF is fairly easy to check with a multimeter

[novasource]

Sounds like the Mass Airflow Sensor

Possible, but seems like MAF should cause more problems than just warm startup. And wouldn't it trigger a check engine light?

[novasource]

This is kind of interesting, but it's now 3.5 years later and still have the same problem. I haven't changed anything out, and I don't think anything running abnormally.