Thunderbolt IV ignition questions

[figaro]

Re: Thunderbolt IV ignition questions

Hi guys,

I'm chasing down a TBIV issue and I don't want to beat a dead horse; I would just like some quick sanity checks.

The problem started at the end of last year, and I dd the diagnostics check, and I thought the problem was the pick up in the dizzy because I would have spark when tapping to ground.

I replaced it...still no spark.

I disconnected the grey wire from the tach...still no spark.

So I checked all the connetions again and again, and then swapped coils. Still no Spark

I went ahead and found a used TBIV module and put it on...still no spark.

I hooked a testlight in-line (purple wire - test light - + on coil) The light did not blink as I was cranking...seems to me that woudl be a faulty pick up in the distributor, even though it's a brand new one.


I guess I was just wondering what you guys though, and if there was anything else I need to check? there's 12 plus, volts at the key on.

Thanks.

is the dizzy actually spinning ? ,all your grounds to the engine /module good ? new pickup not nessesarily good

 

[PowerAddict]

Re: Thunderbolt IV ignition questions

View attachment 195340

Here is the TB trouubleshooting chart. I have the TB4/5 manual if you need it.

Thanks,

I've done the troubleshooting chart, as mentioned. Led me to a bad distributor pick-up. which I bought a brand new one.

is the dizzy actually spinning ? ,all your grounds to the engine /module good ? new pickup not nessesarily good

Distributor is spinning, and I thought maybe I had a bad power or bad ground, So I hooked a jumper cable from the negative on the battery to the block, and positive on the battery to the main power. Still no luck.

I'm beginning to believe the new pick up is bad.

 

[dingdongs]

Re: Thunderbolt IV ignition questions

Do you have the correct sensor in the distributer.
Do you have 12v on the red white wire that is coming from module to sensor?
Have you checked coil is getting 12v.when did you see a spark out of it last.
www.youtube.com/watch?v=rJYJ3KvPhhY‎

 

[PowerAddict]

Re: Thunderbolt IV ignition questions

Do you have the correct sensor in the distributer.
Do you have 12v on the red white wire that is coming from module to sensor?
Have you checked coil is getting 12v.when did you see a spark out of it last.
Ignition Coil - How to Test - YouTube

1. Good question, I ASSume it is the right one, it looked just like the old one that i pulled out. I'll try and verify that.
2. I will have to check that again, I don't remember at this point.
3. I Coil is getting 12V. Haven't had spark since the end of last season.

 

[iownaboat]

Re: Thunderbolt IV ignition questions

Im not sure if this will help or not , I had a similar issue and it turned out to be an extra ground wire that came with the new module. just a thought

 

[PowerAddict]

Re: Thunderbolt IV ignition questions

This may help alot actually. Can you tell me more about the issue?

 

[PowerAddict]

Re: Thunderbolt IV ignition questions

Would it be possible for a bad starter to cause a huge enough voltage drop for the module not to work?

 

[achris]

Re: Thunderbolt IV ignition questions

Would it be possible for a bad starter to cause a huge enough voltage drop for the module not to work?

Yes... What voltage are you reading at the coil positive while the engine is cranking?

Chris.....

 

[04fxdwgi]

Re: Thunderbolt IV ignition questions

Would it be possible for a bad starter to cause a huge enough voltage drop for the module not to work?

An excessive current draw on an iffy starter can pull the voltage down on a battery to a point that electronics don't like to work properly, but I would be checking all the battery connections, and every connection from the battery, to the block ground and starter connections. Starters have a tendancy to be good or all bad, but can start to draw excessive amps if a winding shorts out. Also, have the battery(s) tested to see if they are good, as they will degrade with age. The cable connection points can be a major source of gremlins. Put a volt meter across the battery terminals and check the voltage while cranking. You can also connect a voltmeter between the engine block and the battery negetive to see if any voltage registers during cranking. If there is a voltage there (should be none) then there is a bade ground connection somewhere.