Help my G35 is Stalling on a Warm Start

F

Fire0nic3FX

Member
Sorry for all of these questions. Since I just got the car I'm still curious about stuff. I got all the other issues sorted out with the car but I have one more issue I need to take of.

If I've driven the car for a long time then I go and park it for maybe 15-20 minutes and come back to start it the car either takes a long time to fire up. The starter cranks but the engine won't fire. Or sometimes when it does the engine fires up and the car shakes and sputters to the point the engine sounds like it wants to stall.

I'm confused on what to do. I already tried this stuff:

1. Cleaned throttle body and reset ecu, idle, and pedal learning

2. Cleaned MAF sensor

3. Changed spark plugs

I don't know what what else to do. Can anyone help????
 
Maybe a fuel issue. On my old car, I had the exact same symptoms, but it was related to large aftermarket fuel injectors. Basically when the car was warm, the fuel pressure was high and the injectors would flood the motor. So it would turn over, but not fire. Then when it did, it would stumble for a while until it would level out.

I know your car has stock fuel system, but maybe there's a problem with the pump or something just because the symptoms sound like it's flooding. The MAF doesn't really do anything on startup (you can unplug the MAF and the car will still start). Plugs shouldn't cause it to not start. And I've never seen a throttle body get so dirty the car doesn't fire.
 
has it been wet lately? could be wet spark plug coil from condensation? when was the last time you filled up gas? maybe you got bad gas?
 
Should I try some fuel cleaner? I like using techron but never tried it on my G.

how do I know its a fuel issue? I'm also getting terrible fuel economy. I lose half a tank of gas driving 100 miles. I have to refuel like twice a week.

---------- Post added at 04:19 PM ---------- Previous post was at 04:18 PM ----------

No it hasn't been wet. Does it all the time.
 
IMO, fuel cleaner is useless. This is coming from someone who used to be sponsored by Valvoline and had cases of their products. I never noticed any difference in any of my cars and used it religiously. It's more of a "keeps problems from occuring" product. It's not much different than the detergents already in gas. If you're having terrible economy, maybe an injector is failing and stuck open? That could cause warm start issues as well. Or failing fuel pump or clogged fuel filter (in the pump anyways). I'm leaning toward fuel pump though because a leaking/stuck injector causes rough idle and some other issues as well. Plus it won't keep your car from starting. I had a leaking injector before and the car would always start, but idle rough.

No idea how to really diagnose though. Any codes?
 
i owned a g35 coupe before and based on what your car is doing, you might want to check the cam sensor.. there are two (passenger side & driver side), both easily ( well at least the passenger side) replaced by one bolt per located behind the engine.. maybe the previous owner deleted the codes when it was thrown out and did not replace the sensors.. not sure if you can still pull out previous codes once deleted.. anyway i had the same problem.. was driving on the freeway then all of a sudden, car went into limp mode.. car won't go faster than 40mph.. nav directing me to nearest infiniti dealer.. car died pulled over and tried to start the car.. initially just cranked but started up car just went into a violent shake.. drove it home.. codes were thrown on nav.. replaced cam sensor passenger side myself($60 on pep boys).. infiniti wanted $350 on qoute..
 
av8or said:
i owned a g35 coupe before and based on what your car is doing, you might want to check the cam sensor.. there are two (passenger side & driver side), both easily ( well at least the passenger side) replaced by one bolt per located behind the engine.. maybe the previous owner deleted the codes when it was thrown out and did not replace the sensors.. not sure if you can still pull out previous codes once deleted.. anyway i had the same problem.. was driving on the freeway then all of a sudden, car went into limp mode.. car won't go faster than 40mph.. nav directing me to nearest infiniti dealer.. car died pulled over and tried to start the car.. initially just cranked but started up car just went into a violent shake.. drove it home.. codes were thrown on nav.. replaced cam sensor passenger side myself($60 on pep boys).. infiniti wanted $350 on qoute..
Click to expand...

:plus1: Cam sensors are very common problem with VQ motors
 
Yeah I'm not getting no codes or lights on. I even had autozone check with a scanner for any pending codes and nothing came up.

How do I know which sensor is going bad if there is two? If they were going bad wouldn't they throw a code?

---------- Post added at 06:18 PM ---------- Previous post was at 06:17 PM ----------

My car doesn't die or go into limp mode when driving. It just does this when starting. Also something else to note is that when the car stalls and sputters when I start the car the rpm dips lows and jumps back up. The car ups the rpm to keep it from dying. If I rev it the car stops sputtering.
 
OP, have you solved this problem yet? Having the same issues... Trying to minimize expense but I can't replicate this problem. I think throttle body cleaning / air filter replacement would cause startup issues in both cold and hot but I seem to be having problem only in the heat.
 
You must log in or register to reply here.
Back
Top