So i picked up an ‘07 g35 and ever since i got it the rpm’s have been kinda weird. When i just let it sit the rpm’s will fluctuate from like 650-1300 usually stays right around 1000. When i put the clutch in while driving it also shoots up fo about 1800-2000. I thought that it might be the throttle body so i took it out and cleaned it (it was nasty) but that didn’t help. Yes, i have done the ecu/idle reset procedure, probsbly 4 times. Could it be the MAF sensor? Could it be worse? I would like to get it fixed but i would hate to bring it to a shop and have to pay $100 in diagnostics haha, thanks for any help.

P.S , there is a ripped hose on my intake (i don’t know what the hose is used for so i’m not sure if that could very well be the issue, which i need to fix it cause i don’t want bad air getting into my intake.)

 

Yes a vacuum leak will absolutely cause a high surging idle. Fix the obviously broken stuff then see if it's still malfunctioning.

 

also check coolant level... low coolant can cause a car to surge up and down. Usually vacuum leak will make the car hunt for an idle in most cases...

 

• Quote:

  Originally Posted by mqcah

  So i picked up an ‘07 g35 and ever since i got it the rpm’s have been kinda weird. When i just let it sit the rpm’s will fluctuate from like 650-1300 usually stays right around 1000. When i put the clutch in while driving it also shoots up fo about 1800-2000. I thought that it might be the throttle body so i took it out and cleaned it (it was nasty) but that didn’t help. Yes, i have done the ecu/idle reset procedure, probsbly 4 times. Could it be the MAF sensor? Could it be worse? I would like to get it fixed but i would hate to bring it to a shop and have to pay $100 in diagnostics. haha, thanks for any help.

 

If after fixing the ripped hose, it still hunts, I would start checking around the top of the engine for other possible leaks, such as the crossover tube from the valve covers, the PCV valve, any clamps that might be missing. I, for example, discovered a crack in my crossover hose but only after pressing on it, as it was a hairline crack all the way down the hose.

Good luck and report back what you found.