I just measured 30 - 34 ohms from the negative battery terminal to the block. Do you guys think it would make a difference to add a ground strap to try to reduce the resistance further? Or is ~30 ohms OK?
I just measured 30 - 34 ohms from the negative battery terminal to the block. Do you guys think it would make a difference to add a ground strap to try to reduce the resistance further? Or is ~30 ohms OK?
give it a try its literly under a $5 mod, and may be verry well worth it, and should only take up 10min worth of your time
gotta remember everywone..electricity flows from negitive to positive not positive to negitive...the more the ground the better, even if your a radio nut like me
Essentially, the sum of the currents entering a node (component) equals the sum of the currents leaving a node.
So, as far as power handling capability, your positive side should be the same as your negative side, since the current flow is equal both going into and leaving the component, whether you use whole flow or electron flow as your way of making sense of electricity.
I just measured 30 - 34 ohms from the negative battery terminal to the block. Do you guys think it would make a difference to add a ground strap to try to reduce the resistance further? Or is ~30 ohms OK?
I normally check this in volts, not ohms - gives a better idea what you are losing - ohms is kinda vague for most people. yes, you will see a voltage. thats the voltage that is NOT making it to your starter, headlights, window motors, etc.
I normally check this in volts, not ohms - gives a better idea what you are losing - ohms is kinda vague for most people. yes, you will see a voltage. thats the voltage that is NOT making it to your starter, headlights, window motors, etc.
So you're saying to measure it while the engine is running? All I was doing was checking static resistance between the block and the negative battery terminal. The resistance is what we're trying to fix. If you measure voltage, couldn't that indicate other things than just a bad ground?
Originally posted by mize: So you're saying to measure it while the engine is running? All I was doing was checking static resistance between the block and the negative battery terminal. The resistance is what we're trying to fix. If you measure voltage, couldn't that indicate other things than just a bad ground?
running, not running, while starting - all three will give you idea on how bad your ground is. no, it tell you only the voltage drop caused by the resistance in the battery to block connectoin - ie ground
Also the resistance will change depending on the load thru the connection. IE when you measure the resistance you are measuring it static or kind of under idea conditions.
When you measure the voltage difference from the engine to the batt. your measuring under real conditions.
With high current flows the resistance will change as connections heat up from the current possibly making a big change in the resistance. The only way you can measure the real resistance is by knowing the actual current flowing and dividing that into the voltage drop. Since you can't easily measure the current (at least not when starting) any voltage drop is a bad thing.
Just to give an example. Let's say the cable and connections from the batt. to the starter have only .02 ohms of resistance. That does not sound like much right! Now you start your engine, what do your think it might pull for current 50 amps sound reasonable? .02 X 50 = 1 volt lost. So your starter is already down to 11 volts. If you have ever had a dirty batt. connection and touched it after you have started the car they can get really hot.
Bottom line. If you are measuring a voltage drop, correct the problem however you can....
Well, I stuck to using the static resistance using a DVOM between a couple of points on the engine and the negative battery terminal. I added two ground straps and (for comparison sake) now measure ~.01 ohms. The idle is better...still hunts a small amount, but that may be due to the ECM getting reset.
I am happy I did this simple "mod". Now I have to figure out why my tach always reads 200 RPM higher than the ALDL output says.
if there is enough Intrest in doing this mod i will throw to gether a redy to install "Kit" that will include the ready to install NEW "HIGH Preformance " Ground Strap, full color Photo's and a full List of detailed instructions For the Introductory LOW-LOW price of Just $19.95..... But wait.... Act Now and you will Also recive......
Ahh nevermind
Actually, you could get a pretty good price out of most of us for a kit to repalce all the ground straps with additional ones where you think they are needed. Personally, I'd appreciate a simple writeup with lengths and pictures of the locations a lot more.
[This message has been edited by HellYes (edited 02-12-2006).]
if you were to go pick up like 3-4' of 4 gauge power or heavy duty welding ground wire and some 4ga. ring treminals it would cost you under $10 $15 topps, i just picked up 8 4 ga ring terminals from menards for under $3 it was 2 packs 4 pcs each and i think it was $1.19 each pack of 4 i happened to have some 4 gauge arround in the garage
currently im running one from the egr solonid bolt to the chassie by the battery tray, one from the same spot on the battery tray area to the - on the bat, and one from the lower decklid hinge bolt to the - on the bat.
just take the cable and lay it out in the desired area to find out the desired length and mark it and cut
you could do all 3 of these grounds like i have done for under $15 im sure.... if i were to make up a kit by the time i facter in $5 ish for shipping and like a few $$ for my time and effort.. its not really worth it for me to make them and sell them for like $25 shipped when it is somthing that is soo simple of a DIY i mean all you need to do is operate a wire strippers and a ratchet and a crimper or even a hammer if needed to crimp the ring terminals on
maybe one of these days ill update my pics with the added straps i have on the decklid hinge and such
I just did this mod, though I did not measure the resistance before and after. I can tell you that the idle is slightly smoother and someone said the wipers wipe faster and they do! Mine wipe slightly faster (noticable). not as dramatic as I acpected but worth the $4~ for the cable from the auto store.
just wanted to post to keep this GREAT thread up top. I have spent the last 3 weeks + dealing with codes... ='s replaced IAC, O2, TPS, swapped MAP from parts car, cleaned EGR, swapped EGR selenoid from parts car, all because of a stumble at initial take off that turned to bucking at certain RPM's...worst in 4th gear. Ended up with codes 13 & 21 STILL , also went from 24mpg to 12mpg through all this!!!!!!! Well NOW I believe/hope/pray I have found the answer to My problems. As it is dark I'll do this Tomorrow after work...it will be GREAT to give My sis Her car back and get My "Street Legal Go-Cart" back : ) : ) : ) THX $Rich$
this is a timeless post that should stay near the top for all to see. I would add a few things to do while shredding yourself under the hood: 1. at the left side of the foward head are 2 grounds, clean them up carefully and reinstall. easy to do when the engine is out, rough to do when installed, both these are ecm grounds and need to be good. on the manual, there is another one at low foward bell housing to block bolt, not sure where it is on the auto, clean that one as well. 2. when installing new grounds remember to clean and use star type washers that will contact the ring with the teeth all the way around, and install to a well cleaned surface. notice the factory ones all use star types, this is t assure a good mechanical contact, not to act just as a lockwasher. 3. if possible, solder the crimped in wire, will stop future corrosion there, more important in damp areas and northern areas where you have salt. 4. after installing a new ground and cleaning the surface, a lite coat of paint will do wonders to keep the area protected from moisture that will wick under the connection points and grow corrosion, again more important in damp areas. corrosion = resistance.
adding grounds is a safety net, the more you have, the less chance of a problem. even if all get some corrosion, resistance is reduced with parallel connections, so you are less likely to get stranded in a worst case scenario.
+'s to $Rich$ for keeping this out there.
------------------ 88 GT 2.8l 5spd 76 30' ChrisCraft Tournament S/F who has time for anything else?
Well after reading nearly the entire thread I think I am going to try this tomorrow. I just picked up my Fiero and it starting to run smoother as it gets warmer, but hopefully adding a couple new grounds will help more. Unlike my other cars the cold really affects how smooth this car runs. If I get it done I'll let everyone know how it turned out.
Ok so I added two ground wires to the engine, and well not a huge difference, the car does idle a bit smoother, both headlights pop-up at the same time, seems to accelerate smoother, and attracts better looking women at the gas station lol.
I 've also added 2 ground first between the battery and the chassis, then between the chassis and the engine...
see below:
I noticed some differences! -engine starts quickly -idle smoother -windows go up/down quickly -headlights pop up quickly -lights are brighter -finally idles at 900, and before at 975
finally, it's much much better with these ground straps!!!
just thought i would chime in, i haven't read every post, so just correct me if someone has already said this. What you all are doing is something very common in the car audio world, usually referred to as the "big 3"
Awsome Post!! I cant wiat to try this myself. Totaly makes sense. Ohms law Voltage x resistance= current. The lower the resistance the more current flow, and less of a voltage drop. These cars have so many sensors that need to have all the parameters on the mark, not to mention the ECM. What happens is if the voltage is erratic going to the ECM all of the drive transistors, IC's etc will not see the correct voltages they need to see to "turn on and off" correctly. I know this as I used to repair audio gear for a living and seen first hand what bad grounds can do. Since the dist modual needs to have proper ground, I wonder what would happen if a grounded was added directly to the dist to battery gnd?????
this is a timeless post that should stay near the top for all to see.
I guess that is my motivation for chiming in...
Based on all of Rich'$ other post's I knew that this would be a profitable thing to do, but for whatever reason, when wrenching on my car I forgot about this avice or I put it on the back burner. After adding the new ground strap, the difference in performance was incredible....idling, acceleration, and shifting were the most obvious improvements. At the same time I decided to replace the battery cables because quite a few years ago while working on another car, I was amazed how much corrosion was in a positive battery cable when I stripped the insulation off, and my Fiero just turned 20, so I figured it was time. Someone asked earlier about the benefit of doing the same thing on a Duke, If I still had my Dukemobile, it would definitely be getting the same treatment, the cost and time versus the potential benefit makes this upgrade a no brainer. Rich gave me a ground, but I gave him a positive a long time ago.... Thanks again to Cliff also for keeping the forum running smoothly.
Go out and buy some copper conductive grease and disconeect the grounds from your block, clean the connection point to super clean and shiney and then apply the grease then put the connection back on. From my past experience with a 2m4 the fiero benefits from this big time. IT limits the amount of corrosion and also gives you a better connection because of the copper in the grease getting smushed between the bolt and block.
Although almost all Fieros can do with new battery cables about every 5 years.
ues, i should add that it helps in the long run to use the copper grease or i just use the clear electro cundictive grease, the same stuff you should be using on your plug wire boots
I just HAD to add this. I was having , what I thought was a starter issue. After crawling under the car and dreading even trying to replace the starter I decided to give Rich's idea a try. Up to this point I had been cranking the engine to where the battery would discharge. Replaced the ground strap and NO MORE starting problems. Lights appear to be brighter, especially in the trunk, which I guess is where you would notice it first.
I added the ground from the battery to the EGR solenoid and it seemed to help alittle, but my gauges are still kinda dim, my windows are still pretty slow, i have to push the button for my door locks twice, my turn signals almost stop when i have the headlights on but when they are off it is kinda slow but not nearly as bad, and my headlights are dim as well. I think i may just need new headlights cause i have not replaced them since i have owned the car, but i dont know about the windows and gauges. It has a new alternator and battery if that helps. Any suggestions? Any other place that needs to be grounded that would help a little? Thanks
Disconnecting the negative cable first is a good idea because that way if the wrench hits anything, no sparks! You can almost weld with the amps a battery puts out!! Now the positive cable can be disconnected (if you need to clean it) and if the wrench hits the frame, no sparks. Reconnect positive first, then negative.
Hey, I'm doing this mod and looking at all this negative cable, grounding and all then I looked at the puny positive wire. The large cable goes directly to the starter and nowhere else. The smaller wire, and I mean smaller! goes to power ALL of the car's power. Doesn't that seem kind of a small wire with headlights, wiper, A/C on, cooling fan, etc all at the same time?? Am I missing something or would it be a good idea to run another positive wire to the fuse block? Whatcha think out there?
Sport Compact Car did an article on this a while back. They were actually showing horsepower gains by using better grounding to the engine block.
They were grounding the ignition coils on their K20 engine, which has a coil-on-plug DIS, something I never thought of on my Mazda6 when I added the MSD Stacker 8 box. Grounding something that is the basis of making power, can make you more power, you see they only got 1 to 2 WHP more, which could very well be dismissed as a difference in dyno conditions (Hot Rod or CHP did an article on dyno tricks that netted anywhere from 1 to 2 WHP to 13 WHP more). Though these types of grounds here are for fixing problems and to prevent electrolysis of the cooling system. Ever had severe and constant water pump or heater core failures on an older car? More than likely a bad ground somewhere and your coolant carried an electrical charge.
