Intermitent slow/no starting New problem...

[bbob203]

Just got home its as if my battery is totally dead as a door nail..

[bbob203]

pardon the ignorance how does one perform a voltage drop test?

[TylerDurden]

Recharge battery with external charger overnight.

Tomorrow, crank with a DMM black probe on the battery neg, use red probe on the other connections (starting with the battery pos) - see if/where it falls below 11V.

Bad connection to Batt or alt can fail to charge.

[TylerDurden]

Forgot to say disconnect the fuel cutoff to test cranking/voltage.

[burn_your_money]

If your battery is dead, you probably have something drawing some amps that shouldn't be so I'd look into that first

Voltage drop test how-to
http://www.vwdiesel.net/forum/index.php?topic=22321.0

[8v-of-fury]

edit: and its kinda ghetto how its spliced in. Casing stripped of about 3/8 of an inch section and wire wrapped around it and taped up.

That is a legitimate wire splice, called a T-splice.



X3.8 on the voltage drop test.

[745 turbogreasel]

Also might be worth your while to hit the starter solenoid output terminal with a jumper cable.  if it pulls 500 amp, and still hardly cranks with no load, the starter is the problem.
Obviously be in neutral just in case.

[8v-of-fury]

I have done a starter jump from the engine bay with the car in gear.. WOOWEE she jumps forward with a gut lurch when your leaning on the core support! lmao

[bbob203]

can someone explain this starter jumper test deal better?

[TylerDurden]

You can energize the starter by jumping +12 to the starter solenoid small terminal... but if the car is in gear, it can run u over.


Intermittent slow crank is usually poor connections, bad bushing, worn brushes/commutator.

Dead battery is usually bad connections, lose belt, old battery, persistent current draw (short, stuck relay).

[bbob203]

Welp new battery, Big fat 2ga negative terminal grounded to the transmission bellhousing bolt. Tightened belts and Im firing off in half a crank. 1000ca 850cca battery group 34/78 dual terminal options on it. I think i may run a nice big wire from my alt to my battery via the positive side post.

I think my problem was a really wimpy ground causing bad voltage drop causing weak cranking and heating up wires all through the car.

As soon as i got it all hooked back up 1 cycle of the glowplugs no cs lever 34 degree it spun right up as if it hadn't been sitting lifeless for a month.

[8v-of-fury]

Love it, great success story! I too just got a 34/78 (1050CA 875CCA) and it spins the engine so DAMN fast.

My up and coming upgrades will also include;

• Big gauge battery cables
• Remove the starter and clean up the starter to trans mating surface
• Big body to battery ground
• Bigger gauge between alternator and battery (being that I have a 120A alternator.. it stands to pass quite the amount of current!)
• An entire tube of die-electric grease