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Discussion Starter · #1 ·
Right now I have been running rich almost randomly. The problem would come and go every few months and I would lose some performance. I found after moving my lengthened MAF ground wire the engine would return to normal. However I've replaced as much wire as I could before the wires lead to the huge wire bundle. I think there may be a break inside the insulation further down the wire that I can't get to. Would it work if i took my MAF ground wire and put a wire right to the battery ground? Is there any danger doing this?
 

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I would like to know this too.... Subbing....
 

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well with the way electricity flows its gotta go from a power to a ground, and technically a ground is a ground if it is on the same chassis, and the pcm is gonna get its power from the battery, so i mean you can try it worse case, you get a check engine light for like no maf input or something like that
 

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Or something could happen and you could maybe fry the MAF (Don't think that this is possible since the MAF would still have a ground to route the electricity)..... I would test this but I can't afford a new MAF right now so I don't want to till someone else does it first :)
 

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First check the resistance the MAF ground has with the chassis point you want to ground it to.

If you can measure a slight resistance, then that's because it's got an unefficient ground path to take.

Then it may be worth grounding...

I sort of took this approach with my grounding kit.
 

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I suck at using my voltmeter (I'm sure that is not what it's called). What is the setting on it to check for resistance? Is the the ohms setting? Can you post a pic of the setting you would use? Do I just use the black probe?
 

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A cheap multimeter might show any big resistances:

http://www.8886.co.uk/ref/ohm_meter.htm

You set it to the horse shoe symbol "omega" in the most sensitive setting and use the black and red wires. Connect the leads so that it measures resistance. Test the setup by touching the two leads together and it should read "0" resistance.

Though to measure very fine resistances you use an ammeter along with your voltmeter.

http://en.wikipedia.org/wiki/Ammeter

If I remember, I think it would be beneficial to everyone to know the what parts of the car's electrical system benefit the most from adding an auxillary grounding wire. Measured with the ammeter/voltmeter method.

What's interesting is an ammeter works on the same principal as an inductive loop sensor. An inductive loop sensor is those circles or lines you see at stoplight intersections that tell the stop light that a car is waiting at the red light. These sensors are basically wires sawcut in the asphalt forming Loops. When a large piece of metal/iron goes inside the loop (Such as your chassis/engine), then the electrical signal changes. This tells the light that a car is there.

The sensors function by the metal in cars, not by the weight which is why motorcycles sometimes have hard times setting off the sensors.

Ok that's enough science for the day...
 

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Discussion Starter · #9 ·
I got the multimeter out and found out it already had a perfect ground:-( I even tried moving the wire around lightly and couldn't find anything out of the norm. I reset the battery to see if that helps.
 

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The best ground on your car is the negative terminal.... That's the reference point (zero voltage) for everything. If you want, you can add a big, 6-8 gauge, and run it to a splitter block that is attached to the body. That should add grounding for everything.

 

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[quote author=vctrmaso1 link=topic=137427.msg2963038#msg2963038 date=1235668744]
Right now I have been running rich almost randomly. The problem would come and go every few months and I would lose some performance. I found after moving my lengthened MAF ground wire the engine would return to normal. However I've replaced as much wire as I could before the wires lead to the huge wire bundle. I think there may be a break inside the insulation further down the wire that I can't get to. Would it work if i took my MAF ground wire and put a wire right to the battery ground? Is there any danger doing this?
[/quote]

absolutely. this is one of the first things recommended on sr20-forum for se-r's. HOWEVER you want to look up a wiring diagram and find the STOCK GROUNDING LOCATION for the MAFS. if you ground to a different location it can mess with the reference voltage signals for the ECM.

also do not replace the ground, simply splice into it.

say the MAFS harness' stock grounding location is on the engine block under the intake. you will want to splice in a new ground (larger wire is good) to under the intake. dosent have the be the EXACT same bolt, but close enough.
 

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Discussion Starter · #13 ·
[quote author=aminzer link=topic=137427.msg2966362#msg2966362 date=1235787311]
just out of curosity i re read your first post what is making you say youve been running rich
[/quote]
I own a scangauge 2 with Add a gauge. It allows me to look at the short term fuel trim. When the car isn't running to well i notice my STFT is around -3 at idle and after a few days I get the cel code p2188. The check engine light hasn't come on or the STFT running rich since I reset the battery in my previous post. However I am looking for more possible fixes as I believe the car will start running rich again.

Also where specifically should I try to splice in the new ground? Is it where my CAI is being held up? Or is it closer to the engine.
 
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