weird starter issue

s3landy · March 05, 2019, 12:36 PM

No these were just static readings. The ignition wire on the starter is actually reading around 11.6,11.7v while cranking.

Mike

Red90 · March 05, 2019, 12:56 PM

Sounds like the switch is in bad shape. What year and engine are we talking about?

s3landy · March 05, 2019, 01:08 PM

It is a 1996 130 with a 300 tdi

B-Red · March 05, 2019, 01:34 PM

You have a 10% voltage drop which is high. Try using electrical connector lubricant to improve bonding and connectivity.
Check wiring loom for perched wires or stripped insulation.
Those two items with what you did so far should eliminate a potential wiring issue.
Emad

Red90 · March 05, 2019, 02:17 PM

Quote from: s3landy on March 05, 2019, 01:08 PM
It is a 1996 130 with a 300 tdi

Okay, so that matters. There is a relay between the ignition switch and the starter solenoid. You "may" also have an immobilizer in the line. This is all very important to troubleshoot the system. See attached. I would start by looking at the engine fuse box and the wires from the battery to it and back into the vehicle. Make sure the fuses are good. Then have a look at the starter relay.

s3landy · March 05, 2019, 03:30 PM

The relay is at the bottom of the fuse panel inside. I tried swapping the two relays out and No difference. I don't have an immobilizer. Fuses in the engine compartment are good. If the voltage is higher coming into the ignition switch than it is, going out, wouldn't that mean the drop should be in the switch?

Red90 · March 05, 2019, 03:50 PM

The switch does not matter as the relay is sending power to the starter.

s3landy · March 05, 2019, 03:53 PM

So I guess I should check input at the relay?

Red90 · March 05, 2019, 05:05 PM

Follow the wiring back until you find the location of the voltage drop.

ugly_90 · March 05, 2019, 05:59 PM

As you might be lacking a high-current ammeter, what do the headlights do while attempting to crank? You would have the headlamps on before attempting to start, having an assistant watch them for you.

Do they work at all? Do they dim slightly with your starting? Is there no effect to those lamps?

s3landy · March 05, 2019, 06:28 PM

I will check again when I get back from work. Gives me lots to dig into, thanks

Mike

VA7ZD · March 07, 2019, 08:56 PM

Mike
Did you have any troubles before installing the second battery?
The only thing I can add is to pull the starter and have a look at the ring gear on the flywheel. An engine always stops on one of 4 places (on a 4cyl, one of 6 places on a 6cyl and so on). The ring gear eventually takes a beating and causes starter engaging issues. One quick way to test it is to bar the engine over a bit and see if the problem goes away. If it does, your ring gear is likely the issue.
Good luck
Ian

ugly_90 · March 09, 2019, 04:58 PM

Depending on the results of that headlight test while attempting the crank, the same assistant can provide a moderate tapping on a failing starter with a smaller hammer while attempting to crank. This can allow the starter to spin, and has got me out of jams before on some old trucks.

Did either starter spin when removed from vehicle and tested on a battery?