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-   2nd Gen F.A.Q.'s (https://www.nopistons.com/2nd-gen-f-q-s-44/)
-   -   Fc Grounding 3800 Rpm Stumble, Etc... (https://www.nopistons.com/2nd-gen-f-q-s-44/fc-grounding-3800-rpm-stumble-etc-45685/)

phinsup 03-05-2005 11:46 PM

I am throwing this up to for the most part cover grounding of the FC, T2 and NA. The 3800RPM stumble has been linked to grounding issues another common issue is the tach not working.



There are a few primary grounds, I decided to get a generic grounding kit from one of my vendors, there are many sources, including ebay for cheap grounding. I ended up grounding everything to a block on the negative terminal, either using the factory grounds or your own setup using some 8 guage or better wire, there a few points to pay special attention too.



Tach issues are often linked to a ground on the tranny, this ground uses one of the bolts on the clutch slave cylinder, there is a small square black plastic box that connects to this ground, I grounded this directly to the battery as I mentioned, you may also use the ground on the firewall near the wiper motor, pasenger side.



Next is the block, there are a couple places to do this, most suitable is near the rear of the engine on top, anything fastened firmly should work.



Next is the braided ground coming from the ECU, in my case with my NA this had been broken off, I beileve the NA braided ground exits near the alternator, t2 near the block, this ground is designed to go to the block.



There is also a grounding bracket at the back of the intake, which runs to the ground point on the firewall. All of these are common and should be checked, beefed up or repaired. In my case I also grounded the alternator bracket to the batter and the body to the battery.



I have not done the ECU grounding as of yet, but will add to this post as soon as I do (next weekend I hope.)



I will also get some helpful pics up although most I have seen are hard to tell anything from the pics.

donhayes 03-10-2005 02:04 PM

when you regrounded the wires, did you replace the old wires or just hook up the wires where they were grounded and connect that wire somewhere else, like the battery?

phinsup 03-10-2005 02:07 PM


Originally Posted by donhayes' date='Mar 10 2005, 03:03 PM
when you regrounded the wires, did you replace the old wires or just hook up the wires where they were grounded and connect that wire somewhere else, like the battery?




I removed the negative battery cable, which was grounded to the transmission, so the ground from the trans to the battery replaced the old battery cable.



In other cases I left the existing grounds, added new ones to the above points.

ZenRXSeven 03-14-2005 12:20 PM

I had ground wires running all over my engine bay in my '87 TII, but didn't do a damn thing to help my stumble. But when I spliced in extra grounds for the ECU, it eliminated it completely. I used 10g wire and ran it right to the ECU mounting bracket. The only extra ground I have in the engine bay now is one from the neg battery post to a stud on the block where the ac/ps bracket goes.

phinsup 03-14-2005 12:27 PM

Yea I will get some info up about grounding the ECU, good grounds never hurt https://www.nopistons.com/forums/pub...IR#>/smile.png

donhayes 07-04-2005 11:50 PM

I just did some grounding work myself today. I used 4 guage wire. I haven't done the ECU yet but the stumble was significaltly less when i drove it around. SO soon i'm going to do what zenrxseven did and see what happens. I couldn't really tell a big difference but it is nice to know that my electrical is bulletproof.

piston_killer 08-03-2005 06:25 PM

is grounding the cause of my radio, horn, interior rear, and stop lights flickering when i try one of them?

donhayes 08-28-2005 08:23 PM

maybe, but you'd have to check the grounds for those switches. Just adding new grounds won't neccesarlly fix that.

spiney360 02-12-2006 09:42 PM

so the ecu grounds threw the case? if so i think i found one of my problems.. mine is just chillin on the carpet..

machineRX 02-24-2007 11:25 PM

could you throw up some pics of these places i need to look for?


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