so this started about a month ago, IE my 2007 G35 with 138K miles hesitates when taking off only from a complete stop or in reverse but only when warm. I had the throttle bodies, and Mass air flow sensors cleaned, the spark plugs replaced and other ideas? Also when in park or neutral and you rev the engine it does not occur only when in gear and warm IE runs great when cold.

 

^^
Air Filter?
Vacuum leak?
Any codes?

Telcoman

 

Who cleaned the throttle bodies and MAF ? You can clean the MAF by just spraying it with the proper cleaner but the throttle bodies usually will require manual cleaning.

Have you ever tried the various "resets" (ECU reset, idle air volume, etc) ?

 

will try the air filters today and no codes are being thrown

 

my buddy and I cleaned them and made sure not to move the butterfly valves, did the resets (PIA). What I don't get is why does it only do this when warm, when cold it runs great, and only in drive or reverse not if I rev from low RPM in park or neutral?

 

Was the car fully warmed up when you did the idle air learning ? I actually have the Nissan Data Scan app and an ODBII adapter but that reset failed every time until I made sure every condition was met, including setting the parking brake. I was making sure the coolant temp was in spec, battery voltage in spec, radio/lights/climate control system etc etc were all off and until I set the parking brake, it failed. Set the parking brake, it worked instantly.

 

replace the air filters and no difference, how would one diagnose a vacuum leak?

 

 

 

Can't get this damn attachment out lol

 

was yours only sputtering when warm or all the time?

 

 

I had this a while ago on my 2007 G35x 5AT

If memory serves all i did was reset the ECU via a battery disconnect. That cleared it up instantly. Easiest fix worked...for a change!

 

hi new member here from the middle east i have a 08 g35s sedan and it has given me hell from the beginning right now the issue that resides is it takes forever to start when warm but if u put the accelerator pedal down for a while it gets back to its rhythm and is fine otherwise will start up and die the second issue is when the car is in gear like D and I'm at a stop the rpm keeps on going up and down aka rough idle it only does it on idle .... it used to stall before on little breaking and shake badly on constant speed but got that sorted out.
my car has about 150k miles
parts changed in the process are
fuel pump
spark plugs
coils
throttle body
air intakes
maf sensors
temperature sensors
timing sensors
rebuilt ecu

plz help me

 

... or disconnect your battery ... what he said