Starting Issue Unlike Anything I've Seen

[jrandle]

No problem! It's just one of my pet diagnostic peeves (I get this on the phone ALL the time) and figured this was a good time to set some definitions for the list readers.

Dave, one last thing for you. Although I am not doubting the possibility of faulty wiring on the ballast resistor, why would it only happen when the car is hot?

[Jonathan]

Dave, one last thing for you. Although I am not doubting the possibility of faulty wiring on the ballast resistor, why would it only happen when the car is hot?

Not knowing if yours is doing the exact same... until we get to see a picture... but when mine failed in the first season I had it, the mistake in the wiring only showed up after enough things in the car were running. And I mean electrical load like blower fan and I think ultimately the one that put it over the edge was the radiator fans. I don't know exactly all the in's and out's of how that circuit works, but eventually it got hot or misshapen enough to disconnect itself completely from the resistor ends. It's really easy to check though when you or someone else looking at it knows what it is supposed to look like.

[DMCMW Dave]

Dave, one last thing for you. Although I am not doubting the possibility of faulty wiring on the ballast resistor, why would it only happen when the car is hot?

That would tend to point away from the ballast issue. Typically that causes a problem if the battery is low. I probably missed that comment a dozen posts back.

[jrandle]

That would tend to point away from the ballast issue. Typically that causes a problem if the battery is low. I probably missed that comment a dozen posts back.

I would agree with you, but it was a brand new battery. The thought of parasitic drain crossed my mind, but that doesn't explain why there is enough current in the battery to start the car when its cold and a lack of current when it's hot.

[NightFlyer]

I would agree with you, but it was a brand new battery. The thought of parasitic drain crossed my mind, but that doesn't explain why there is enough current in the battery to start the car when its cold and a lack of current when it's hot.

Just because a battery is new doesn't mean that it's good - it could be defective.

I never assume that just because something is new, means that it's good and functioning properly - especially when it comes to car parts. While the probability of a defective product is low, it's always possible that you're the 1 in 1,000,000 guy that ended up with one.

That said, it sounds like you have an ignition issue, that's only evident when things are warm/hot. Heat creates electrical resistance. I'm wondering if a wire isn't getting too hot because it's not routed correctly?

Heat also causes things to expand/swell. A loose ground could be being pushed away from making good contact when things are hot.

I'd check the wiring/grounds.

Also, put a meter on the battery to confirm that you're getting a good output when hot. The alternator might not be charging the battery when/if it gets hot - could be a bad alternator/regulator.

Have you ever let it sit 6+ hours after a no-start without jumping it, and then trying to start it normally? Does it fire if you do this?

Best of luck!t

[jrandle]

Just because a battery is new doesn't mean that it's good - it could be defective.

I never assume that just because something is new, means that it's good and functioning properly - especially when it comes to car parts. While the probability of a defective product is low, it's always possible that you're the 1 in 1,000,000 guy that ended up with one.

That said, it sounds like you have an ignition issue, that's only evident when things are warm/hot. Heat creates electrical resistance. I'm wondering if a wire isn't getting too hot because it's not routed correctly?

Heat also causes things to expand/swell. A loose ground could be being pushed away from making good contact when things are hot.

I'd check the wiring/grounds.

Also, put a meter on the battery to confirm that you're getting a good output when hot. The alternator might not be charging the battery when/if it gets hot - could be a bad alternator/regulator.

Have you ever let it sit 6+ hours after a no-start without jumping it, and then trying to start it normally? Does it fire if you do this?

Best of luck!t

I have let it sit overnight after the event and it starts right up. Also, could some take a good picture of their ballast resistor so i can ensure mine is wired correctly. Please include the relay in the photo.

[Ron]

Ballast-Relay Wiring in Resources Section

[hmcelraft]

That relay provides the added voltage during starting (assuming all is wired properly). New or not it may be losing contact when hot because of faulty points or weak internal coil.

[Ron]

If you suspect the relay, you can temporarily bypass it by replacing the UY wire with the WY wire...Good for an emergency or testing.

Measuring voltage at the coil while cranking and a look at the spark makes the most sense to me...

[NightFlyer]

I also forgot to mention a new Bosch Coil installed.

As I'm thinking that your problem is ignition related:

What kind of Bosch coil? Some of the newer Bosch coils that are made in Mexico and Brazil have caused a heap of trouble for the VW guys. If it's not a Made in Germany or Made in Spain Bosch blue coil with a red top, then try swapping it out for one - if you still have your old coil, swap it back in.

If that doesn't change anything, then check your plug wires, especially the coil to distributor wire. Make sure that all the wires are properly connected to the distributor. If you have your old wires, try swapping them back in.