Air fuel ratio running lean when going uphill
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Guys, I have a 04 350z with Vortech Version 2 tuner kit that was tuned with Uprev. The problem that I'm facing recently is whenever I cruise uphill and I step on my gas paddle half way down, my air fuel ratio will run really lean to 17-18. This happens at around 3k rpm when it tried to build to boost. When this happens, I either tries to give a quick tap on my paddle and the ratio will jump back to 12-13, or I will let go of the gas peddle and go really slow. The car runs fine on flat, or downhill. It felt as if not enough gas is going to the engine when cruising, but normal under heavy load. I hope I explained this well enough, but I will try my best to provide more information if someone points me to the right direction.
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If the tuner doesn't tune it correctly or at all in that RPM/load area on the 2D fuel map you have the same issue. MAP or MAF it doesn't matter. I think what you might be noticing is that there's more bonehead/lazy Uprev tuners specializing in N/A bolt-on tunes (and their F/I tunes end up like this), than Haltech/ProEFI or other MAP based tuners who do F/I much more often.
Last edited by djamps; 08-18-2013 at 08:12 AM.
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can I ask a stupid question here - how do you know and/or what instrument are you taking your information from to come to the conclusion that you are running lean? is it off a laptop w/your tuning software or is it off a stoich gauge?
The reason I ask is my procharger installer back in 2007 tuned my car off my a:f ratio gauge and it was horribly wrong…at WOT I was running a 18:1 when I dyno'd…my point here is if you are reading off a a:f ratio gauge you may want to get a second opinion.
The reason I ask is my procharger installer back in 2007 tuned my car off my a:f ratio gauge and it was horribly wrong…at WOT I was running a 18:1 when I dyno'd…my point here is if you are reading off a a:f ratio gauge you may want to get a second opinion.
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