RPM dips low at idle
#1
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RPM dips low at idle
Lately my car has been dipping below idle when I am stopped at a light. It will dip to maybe 500-600 rpm vibrate a little then go back to 800. Anyone ever dealt with this?
#7
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Are you guys running aftermarket intakes? May have some shputz on the air flow meters from the oiled filters. Also you may want to check your oil level or change your oil since at idle the VVTL system has more to do with air entering the engine then the throttles do and if your are having pressure or vescosity issues from low oil or old oil that could be causing the problem.
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boweld (06-18-2018)
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#9
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Ok thanks guys. I'll be cleaning the TB this saturday morning, and report results afterward. I have stock intake, and I ran Pennzoil Platinum at 17K, car is currently at 20K, Oil looks clean still. I'll change it in a couple weeks to.
#11
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I had the same issue as well, and as it got worse my G actually started to die immediately after start up. Was still under warranty so infiniti replaced my Tb's and put a new computer in too. But cleaning ur TB's should do it!
#12
The VQ37VHR uses the VVEL system to control air flow into the engine. The throttle bodies are just for back up in case the VVEL system fails. Cleaning the throttle bodies wouldn't make any difference.
http://www.nissan-global.com/EN/DOCU...0713VVEL-e.pdf
From that presentation:
http://www.nissan-global.com/EN/DOCU...0713VVEL-e.pdf
From that presentation:
VVEL controls intake amount through intake-valves of the combustion chamber, where conventional engines used throttle valves
#14
The VVEL system allows for a fair bit of valve overlap during startup and while the engine is warming up to help reduce emissions during cold startups. Maybe the rough idle has to do something with that?
#15
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Thread Starter
The VQ37VHR uses the VVEL system to control air flow into the engine. The throttle bodies are just for back up in case the VVEL system fails. Cleaning the throttle bodies wouldn't make any difference.
http://www.nissan-global.com/EN/DOCU...0713VVEL-e.pdf
From that presentation:
http://www.nissan-global.com/EN/DOCU...0713VVEL-e.pdf
From that presentation: