Adrien
Well-Known Member
Here is the ground I’d be suspect of in your case due to the oil leak. I don’t think it necessarily explains the issue, but who knows
Attachments
Last edited:
Long crank, no faults
- Thread starter Jimmy Brooks
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Jimmy Brooks
Full Access Member
Ya I can see the ground to the coil banks in the photo and it’s covered in oil, that’s why I asked if yours was covered in oil as well. Ive had that oil leak for over 3ish years now and wouldn’t be surprised if it corroded that piece making the ground bad, I’ll clean it off and put a multimeter on that ground and on the battery to see if there is any resistance.
Adrien
Well-Known Member
Ok! Yeah multimeter for resistance is a great move, You could also check for resistance between once of the negative/ground pins on one of the coils, and touch the other lead to the cleanest metal surface on the engine itself. If that looks good a quick test from the engine to the frame/fender might be helpful as well.
Another way is you can measure Battery + to -, record that voltage, then measure battery + to any ground you want to test and see if your voltage varies hugely. Set multimeter to 20v for best accuracy, any higher and the drop caused by bad ground might not be noticeable on some meters
Not corrosion, per se; oil prevents corrosion. But it could have encouraged something to loosen, or is forming an insulating layer between things. Cleaning grounds isn't a bad idea anyway.
Jimmy Brooks
Full Access Member
Ok, I am back with some information. When testing the grounds I found that from the coil ground (the middle female pin) to the ground on the engine there is about .5ohms. However from the coil ground to the battery ground I would get fluctuations from 2ohms letting the car sit all the way to 4.5 ohms after opening the drivers side door and then testing. It appears to be that way on both banks. The voltage looked normal when putting one on the battery + and another on the coil ground. Battery voltage was healthy as well.
Edit: when I put the 2 probes together I would get around .3ohms and when I put it on a random ground on the on the body and then on the battery ground I would get around 1-.8ohms.
Edit: when I put the 2 probes together I would get around .3ohms and when I put it on a random ground on the on the body and then on the battery ground I would get around 1-.8ohms.
Last edited:
The driver door changing the reading seems...odd. I suppose if you have a set of jumper cables you could patch directly between battery negative and the ground that the coils attach to to see if it makes any difference in cranking time? Bypass all the connections between the two?
Jimmy Brooks
Full Access Member
Ok I’ll try that and see if it makes a difference, although I’m not sure I’m going to be able to get a jumper cable in that small space
Last edited:
Doesn’t have to be that heavy…even a 16 gauge wire with good connections ought to identify if that helps.
Adrien
Well-Known Member
Trying to remember my circuits lectures in college, increase in resistance from coil to battery makes sense (I think) as when driver door is opened a bunch of modules turn on and therefore begin pumping current through the engine to battery ground. As current increases resistance should increase as well. Again a strong "I think" on this one but I will run the scenario by some friends that are more fluent in circuits and see what they think
Adrien
Well-Known Member
In other news I finally confirmed there is a single capacitor that feeds both banks of coils. I will supply wiring diagram shortly, I'm just having trouble finding it's physical location on the engine at the moment
