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350Z - Starts up rpms drop and turns off

I have a manual 2004 350z Enthusiast that i bought a couple of weeks ago and it ran fine on the way home and started and ran great for a while. One day i turned it on to take it out for a spin and while going out of my driveway in reverse which is faced down a little the car stalled out so i turned it back on and the car started but the rpms dropped and it shut back off. Once again i turned it on and it shut back off so i tried it one more time but gave it gas this time which worked because it stayed on. I went to Autozone and while trying to leave it happened again and this time it happened again on flat ground. The car shakes a bit at idle and the rpms go at about 500 or 600 but the needle dances a bit as well. Also the oil pressure gauge goes up a great amount depending on how much I accelerate, do you have any idea what this could be? I thought it was the mass airflow sensor so I bought a spray and cleaned it (without touching it with my fingers or anything else) it worked for about two days and then started happening again

Try having the electronic throttle body cleaned.

The electronic throttle body is what controls the engine idle anytime the accelerator pedal is released.

Tester

1 Like

It sounds like it is just plain not running well for some reason. Misfiring, problematic air/fuel ratio, or compression problem. Have the compression test done (and check for diagnostic codes), and if that’s all ok, give it a basic tune up.

  • New spark plugs
  • New engine air filter
  • Check valve clearance (if applicable)
  • Check ignition timing, both base and advance
  • Intake manifold vacuum test (for exhaust restrictions)
  • Check fuel trims
2 Likes

Thank you, very helpful. That was something i was looking into and yesterday I checked the throttle body and fount out it was very dirty. I cleaned it and it started up great with normal rpms but I will still be taking it to get the tune up done. The previous owner had the incorrect air filter on the car so maybe dirt and dust built up, I bought a new filter and cleaned the throttle body and Mass airflow sensor

Thank you! I checked the throttle body and it was filthy, I used throttle body cleaner to clean it and it seems to be running better now

Maybe you could quantify this with some numbers or relative amounts? Because this could be concerning. Like the bypass valve is stuck or engine is sludged up…