Since no one helps in the other forum

ONLY for ADVANCED technical discussion about the 240sx!
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Black on Gold
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Well i posted this in the KA section but no replies. I really need help on this because im getting 12mpg which isnt too great for being a Senior in High School so Im coming back to my NICO family on this one. I've been in this rut for the past 2 months. The car wants to run extremely rich and i believe its because of the VAC leaks. I fixed most of them except the farthest one to the right on the Throttle Body. If anyone can show me some pictures of where the line runs too that would be great. Im more of a visual learner then anything.

I tried capping it off but if i do then the car will start but then shut off immediately. Please anyone, i need help on this. Thanks

Pat


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hnsenter
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i think i have the same rims as you. sorry i dont think i can help you on this one. There's been a lot of posts on gas mileage, try looking them up they have a lot of good info out there. is that a carbon fiber hood?

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AZhitman
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Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
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Yo Pat - Have you checked the FSM? There's a good vac diagram in there...

Also, might be time for a full old-fashioned tune-up... Plugs, wires, cap, intake cleaning, ohm the injectors, clean IACV, clean the idle orifice in the TB... Lots of little things you can do to help with mileage.

vancouverbc
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Car: 1991 240sx

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How do you know it is running rich? I'm just curious. Leaking injectors and a bad temperature sensor are two common reasons for running rich. Unplug your o2 sensor and see if that improves things.

vacuum lineshttp://forums.nicoclub.com/zerothread/221905

180fan
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Car: 89 fastback

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Werd, get that vac leak patched up then we'll talk mileage. I was able to squeeze a fair amount of mileage from my sohc waaaay back in the day.

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Black on Gold
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Location: Winterthur, Switzerland

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Thanks alot Greg. I have checked the FSM and all i got was a diagram with where they go but that one didnt help seeing how it was tough to tell which hose was which. A tune up is exactly what im thinking. I've already taken care of the o2, Fuel Pump, Plugs.

hnsenter, it was a CF Hood. Sold it.

Vancouver, i know im running rich because i can smell that gas when i have the window 1/4 the way down and also black smoke out the rear

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Black on Gold
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Did i mention EGR has been removed

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Black on Gold
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Another update. Just checked the Cylinders....im only running on 3. Cylinder 3 has no fire. Had the car idling and pulled out the spark plugs and all of them shocked me but Cylinder 3.

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hnsenter
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i never got shocked removing any of my spark plugs while the car was running..

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Thebigjc
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Car: 1990 240sx/sr20det
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If you have cheaper plugs and wires you can get cross fire. I've had that happen it s not supposed to be good.

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hnsenter
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did u make sure that the spark plugs are on there tight? had that problem with mine.

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Black on Gold
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I'll check tomorrow again. I just bought some Compression Cleaner that is supposed to help with the Piston Rings


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