Trouble starting and cutting out...

[B2 Addict]

Ok, I have my 2.8 D/sparked and have for some time now... I am having trouble with starting, especially if it is raining or damp outside. It will crank and crank before it will finally start, but if I jump start it with cables, it will start 1st time...

The battery has plenty of power and doesn't run down at all. It also tries to cut out and sputter when in higher rpm's, I thought it was in the carb, but now I'm wondering if it is in the ignition system...


B2

 

[Lil-Pony]

Check your alternator and the voltage across the primary of your coil when starting, idle and at high revs. Clean all grounding locations

 

[Twister]

Maybe condensation in dizzy cap?

Sent from my SPH-L900 using Tapatalk 2

 

[RonD]

Check voltage while cranking, that's the voltage the ignition needs to use.

Maybe your older starter is drawing more power now, second battery raise the voltage enough to get a good spark.

I think the duraspark module needs a START wire and a RUN wire, check the START wire.

Not sure on the Duraspark but on older systems the START wire provided 12v as engine was cranking, the RUN wire was only 7v-9v, via a resistor, so the coil wouldn't overheat while engine was running.
The START wire was either hooked up to the Starter motor side of the Solenoid, so it got 12v when cranking, or to a separate "I"(ignition) connection on a 4 post solenoid.


The fact it is cutting out at higher RPM would indicate a wiring problem in the duraspark system, vs an overall system voltage problem.

 

[B2 Addict]

Thanks for all of the suggestions, I will do them all if I get a chance this weekend.

Twister, condensation in the dizzy is a huge possibility, I think I will start with a complete tuneup because it is past due anyway.


B2

 

[RangerSVT]

Allen, check voltage when starting, if its below 10.4 volts when cranking, time to replace the starter, as its pulling more juice to operate, pulling the required voltage away from the duraspark unit to fire, as stated. Check voltage before starting, key off. If voltage is below 12.5, have the battery thoroughly tested, prior to driving the truck, so it doesn't get a fresh charge prior to testing. Moisture is always a problem and possibility, pull the cap and rotor, clean with sand paper or scrape with razor blade. This will pacify til you can replace the parts. Get some dielectric grease, and put a dab on each electrode tip of the cap, and a little on the upper sides of the electrode on the cap, where the plastic meets the electrode. This will ensure both a weather tight seal and trouble free removal of the plug wires. Remember to clean both sides of the electrodes on the cap, as well as the rotor...

SVT

 

[B2 Addict]

Thanks Rick, it is very annoying... Hopefully going to give 'er a good once over tomorrow, I've got a pretty nasty valve cover leak that needs to be addressed soon also...


B2

 

[RangerSVT]

Sounds like time for a v8 swap...

SVT

 

[kimcrwbr1]

If it starts good when you jump it you probably have a bad connection at the battery. When you go to start it do the cable clamp/s get hot. I would start there and see if it fixes the cold start issue. Do you have a ballast resistor on the ignition coil or are you running the stock TFI coil?

 

[enginepaul]

Note on Grounds = the grounding is as important as the positive; the ground completes the circuit.
Spent many hours once with a problem DuraSpark after a tune-up; decided to re-due the tuneup and discovered a lose ground screw was the problem.

Also - generally - the control module is good or bad; it works right or doesn't work at all, so go through the other steps first.

 

[B2 Addict]

Didn't get the chance to get to it this weekend, gonna be taking it to pops shop either Tuesday or Wednesday... Thanks for all of the input!


B2

 

[B2 Addict]

Woo Hoo...

Couldn't find anything wrong today, everything checked out good...

So pops finally decided we would change the D/spark control module, TA DA...
I had that beast up to 6k on the tach with no sputtering and she starts right up!!!!

Here's my new module, from Napa of course...




B2

 

[enginepaul]

Thanks for telling us what happened. That is new to me in as much as I have always found the module is either all good or it fails.
I'm still learning.

 

[wildbill23c]

Could be a heat related problem in those modules. Heat can do some weird things to electronics. Even heat build up under the hood just from sitting in the sun can do weird things, especially on these old vehicles. Kind of like the ignition module on the back of the distributors getting old, then getting hot and shutting the truck down, sadly a friend of mine had an 84 B2 in high school that did that, didn't know back then about those modules so instead of trying to track down the problem he had it hauled to the grave yard.

 

[B2 Addict]

Well, it was definitely the problem. I didn't start it for 2 days and it has been raining, got in it today and it started 1st try!!

It hasn't done that in years and is actually a pleasure to drive again...


B2