Engine to chassis ground...

[Three50won]

I have a question about this. My 95 has been having electrical, starting, and charging issues. First off, it surges a bit at idle to the point that you can see the headlights dimming slightly. The engine cranks slow all the time and sometimes won't crank at all...it even left me stranded (luckily across the street from my home). The battery won't charge and the gauge is always on the low side despite having a new battery and alternator. A few days ago I took the car to have the charging system checked and it came back good.

So yesterday a buddy noticed that I have no engine to chassis ground. There is a 4 gauge braided wire that is connected to the chassis but not to the engine. I would have assumed that the car wouldn't start at all or there would have been more severe problems if there was no ground. But perhaps the fact that I have solid motor mounts helped provide a small albeit inadequate amount of ground. Maybe that's why the previous owner didn't bother to fully address the issue. So now I'm trying to ground the engine and I can't find a good place to use. So the question is, Will I have adequate ground if I connect the ground wire to the solid motor mount or does it have to go directly to the block? And if I can do this, does the wire have to go on the engine side of the mount or does it not matter? If it isn't a good idea to ground it to the solid motor mount then please tell me a good location on the block. Thanks in advance for any help...

 

[Three50won]

Here is an update. I used 24 inch long 4 gauge cable wire with eyelets at both ends. One end is connected to the passenger side chassis by the strut tower and the other is to the block on the passenger side...I found a hole threaded hole there. I have a bolt in it but I have to go back to the parts store to get a bolt that will fit better. So far it seems to be working good. The engine is cranking good and it's getting a good charge. I started it, let it run for a few minutes, and then started it up again 3 times. Each time it cranked really good whereas usually it would be slower to crank after one or two starts. I have to drive it a bit to fully check things but I think it's good. If anyone has any other advice or suggestions then I am all ears...thanks!!

 

[Rick 91GT]

grounds are very important, sounds like you are in a good location.

 

[toyman]

The other thing to look at is the connection from the battery to the engine. Make sure these connections are clean and solid. If I were having the problems described I would consider changing both cables from the battery. Often there is corrosion in the cable itself that is not visible.

 

[Three50won]

The other thing to look at is the connection from the battery to the engine. Make sure these connections are clean and solid. If I were having the problems described I would consider changing both cables from the battery. Often there is corrosion in the cable itself that is not visible.

Thanks toyman...as it is my problem returned. So I have to go back and check the battery ground wire and the alternator wires. I have the battery relocated to the trunk so hopefully I won't have to replace those cables. We will see...

 

[Three50won]

Here is another update (cry for help) on my not so progress. I am still having the problems with my car. After driving for a bit it is still hard to turn over. I did a volt test and the battery checked out fine with the engine on and off. I even checked the alternator where the wire bolts in to it. I am getting 14.4 volts with the engine running....same as at the battery. With the engine off I am getting a little over 12 volts at the battery...I checked this at the terminals and a second time with the positive terminal and a ground source. I checked the negative ground and it looks good. Still tho, my charging gauge is reading low (at the "O" in "NORMAL"). I am completely baffled. I would think that perhaps the gauge is malfunctioning except for the fact that the engine is not cranking properly.

So in a few days I plan to take the car for a long trip to see if the volts change after extensive driving. And when I get home I will try to start it up again and see what happens. Maybe the drive will allow the alternator to charge the battery since I have not driven the car for more the 5 minutes (city driving) since I did the engine to chassis ground. Any further advice/help/experiences is greatly appreciated. Thanks!

 

[toyman]

Just so that you know, testing the voltage and getting a good reading of 12.5v doesn't mean that the battery is up to snuff. You need to do a load test to see what the current cranking amps are. My guess is the battery fresh will have a cranking load rating of 700+/- amps but will now test in the 350 amp range. Any place that sells batteries should be able to do the test for you.

 

[Three50won]

Just so that you know, testing the voltage and getting a good reading of 12.5v doesn't mean that the battery is up to snuff. You need to do a load test to see what the current cranking amps are. My guess is the battery fresh will have a cranking load rating of 700+/- amps but will now test in the 350 amp range. Any place that sells batteries should be able to do the test for you.

Well the battery was new the day before I put the engine to chassis ground on so it hasn't been used too much. Would low amperage cause the gauge to read low? Any case, I will do a load test on Friday. Thanks for the suggestion...keep em coming...

 

[ProKiller]

the stock gauges are worthless, if your only problem was that, then you don't have a problem.

now onto your cranking issue, have you checked the starter? how old is it? do you have longtubes on the car? the chassis ground, are you sure you have a solid ground, no paint in the way on the chassis side? i had a ground issue it was a pain to get rid of.

 

[Three50won]

the stock gauges are worthless, if your only problem was that, then you don't have a problem.

now onto your cranking issue, have you checked the starter? how old is it? do you have longtubes on the car? the chassis ground, are you sure you have a solid ground, no paint in the way on the chassis side? i had a ground issue it was a pain to get rid of.

Hey ProKiller, yea I keep thinking that about the gauge...the only reason I'm inclined to think it's accurate this time is because I'm have legitimate starting and charging issues. As far as the cranking problem, I'm starting to think that it just might be the starter. I had a stock 91 that did the same thing and it turned out to be the starter solenoid. So maybe it's drawing too much from the battery. Even with the battery at 50% charged the engine wouldn't crank over. I don't know how old it is but I'm gonna replace it this week...besides, it's the only thing left that could be the problem.

 

[blksn955.o]

For what it is worth the ground was probably removed when they swapped to solid mounts. The engine to chassis ground is from the drivers side frame rail to the drivers side motor mount stud. The wire is very close to the oil filter.

Have you checked for a short or large draw?

 

[Three50won]

For what it is worth the ground was probably removed when they swapped to solid mounts. The engine to chassis ground is from the drivers side frame rail to the drivers side motor mount stud. The wire is very close to the oil filter.

Have you checked for a short or large draw?

Hey blk...yea you're absolutely right and thanks for the response. The ground wire is there on the driver side frame. It is a flat braided wire but it's not connected to the engine. When I was looking for a location a few days ago I couldn't find a spot that the braided wire would reach which is why I bought a 24" 4 gauge cable and bolted it from the passenger side frame to a bolt just under the alternator bracket. This was the only place where I could ground from the metal on the block to the frame. I didn't look to see if there was a spot by the oil filter for the braided wire because I didn't know that was the location (thanks for the info BTW). And come to think of it, it probably wouldn't reach anyway because it was just ripped off by the previous owner.

How would I go about checking for a draw? I think it's possible that there is a draw because I just drove the car around and my alternator voltage is around 13.9 - 14.2 while the battery voltage is at 13.5. A few days ago the battery AND alternator voltage were both steady at about 13.9 - 14.2...this was from just starting the car once and letting it run. I did crank the car a few times today so maybe that is why the voltage dropped a bit. Sound logical?

 

[DreaMachine]

i was having charging problems with my '95 also,but only in freezing weather. never knew when problem would occur, or for how long. altenator was rebuilt, batt cables replaced, plug-in harness to alt replaced, etc, nothing worked. while charging the battery one day, i took out the courtesy bulb attached to the hood. the car sat for a few days and died again. while charging this time, for some reason i completely unplugged the wires from the courtesy bulb unit under the hood. i have never had another charging problem. i know it sounds crazy, but it worked for me. maybe someone with more knowledge could tell us why. its cheap and easy, maybe worth a try!