911 SC no start Perma Tune question

[Lorenfb]

"However, I do not agree with your assessment of the Perma-Tune."

Have rebuilt many of the original 'blue' Perma-Tunes over the last 20 years.
That unit was as reliable as the Bosch units, which is NOT the case for the
later 'silver' & 'black' units. Too bad Perma-Tune lost the 'recipe' when they
moved from Newport Beach, CA and changed the original design by the
German engineer who was associated with the Verner Von Braun rocket
development in the '40s. His design was written/published in German and
described its uniqueness compared to other CDI designs.

[jimrs2000]

Ok, back from more troubleshooting and I have issolated it to a bad spark from the coil.....its there just not very good.

Checked resistance across the LT connections and got a closed loop, that is no resistance. Does that mean the coil is bad?

Lonnie, I know jim at Euro cars, if I need a coil tomorrow do you think he has them in stock?

[Alan Lindquist]

Three years ago I paid $500 and something for a Permatune (if I remember correctly. I could pull the receipt to be sure). It seemed a better deal than a Bosch replacement. The Permatune lasted three years. The stock Bosch unit had lasted 27 years. We'll see how long the $350 rebuilt Bosch unit lasts. I don't mean to be harsh... it's a math thing.

Originally Posted by Perma-Tune

In the Dallas area there is a really excellent mechanic that runs Dallas Eurocars. He really knows his stuff and is honest as the day is long. Ask for Jim:

Porsche-Lexus Mercedes-Bmw repair in Dallas Ft Worth Tx

Phone (972) 243-4911

Some of you guys are really quick to condemn my product before doing any investigation at all. As it turned out there was nothing wrong with the Perma-Tune.

Bosch makes a really good product too but it fails as well and none of you jump on Bosch like you do Perma-Tune. I do not understand why some of you have such a bad attitude especially given that the most vocal critics have never asked for my help.

Lonnie

631.909.1011

[jimrs2000]

Guys,

Lets let the Perma Tune thing drop and help me with my troubleshooting?????

[Lorenfb]

"Does that mean the coil is bad?"

Now/then buy a cheap ($20-$30) VW coil from O'Reilly, Pep Boys, etc. to test
whether it's the coil or the CDI unit. It doesn't get any simpler than that!
If you still have the original black Bosch coil, then use it. They rarely if ever
fail.

[Joe Bob]

Weellll, we can talk about performance chips....but you have an SC

[Perma-Tune]

What is a megger test

Jim,

Yes, both Jim and Pelican carry the Perma-Tune coil.

The coil primary resistance is going to be a low number so be sure your meter is on the correct setting. Zero Ohms is not normal.

Using an Ohm meter is not a very reliable test for checking a coil anyway. The correct instrument for checking the coil is called a Megger. You can send me the coil to have it checked out at no charge on our equipment. Better still, Loren has a good idea about getting a coil from the local parts store. If you have a Perma-Tune unit on the car there is no danger of damage to the Perma-Tune module due to impedance mismatch. If in fact replacing the coil fixes the car, just leave the cheap coil in the car but replace it if you ever see evidence of oil leaking out of it.

I cannot speak to the Bosch unit coil impedance requirements, maybe Loren knows.

Loren,

I did not know there was a connection between Dr. Theodore Sturm and Dr. Wernher von Braun. I know that Sturm and Ferdinand Porsche were college buddies and latter collaborated on the Ferrari ignition that became the 911 "Blue Box". I have no information on von Braun and would like to know more.

Allen,

Did you send us your Perma-Tune for analysis, did a bench check on it or just replaced it?

[Perma-Tune]

Jim,

P.S. If you send us the coil send the box too.

Perma-Tune Warranty Dept.
3 Grace Court
Center Moriches, NY 11934

631.909.1011

[Lorenfb]

"I did not know there was a connection between Dr. Theodore Sturm and Dr. Wernher von Braun."

He invited me for lunch at his house when I sold semiconductors for Motorola Semi,
e.g. 2N3055, 2N3771, when he was partially retired, a very knowledgeable and interesting guy.

"I cannot speak to the Bosch unit coil impedance requirements, maybe Loren knows."

Check here: http://www.systemsc.com/diagnostic.htm

[Perma-Tune]

Loren,

That is a most impressive web site you have there: a wealth of information.

Von Braun an interesting person? You get the understatement award of the day. This is the guy who invented the first successful chemical booster rocket to reach space! You truly had an experience I would love to hear about.

[Lorenfb]

"That is a most impressive web site you have there: a wealth of information."

Thank you.

Sorry, met only Sturm for lunch. He was very interesting.

[jimrs2000]

Loren,

Can you give me more details on testing the coil with a megger.

I trained as an aircraft engineer (many years ago!!) and I am familiar with insulation testing and I have access to a megger.

[Lorenfb]

"Can you give me more details on testing the coil with a megger."

Have not used one. It is used to check the secondary breakdown voltage or insulation.
You can just measure the primary and secondary using a good Fluke VOM and use the
values shown here for typical CDI coils: Diagnostic as a guide.

The VOM won't provide any info if the secondary is breaking down under
the high voltage, typically 100 X 400 = 40 KV. The best test is to use an oscilloscope
and check the primary pulse to the coil. That will indicate if the CDI or the coil is bad
immediately.

Or, as mentioned before, buy a cheap VW coil for testing and as a spare to keep in the
car. My 911 3.2 has the following spares; fuel pump, coil, rotor, dist. cap., ref/speed
sensor.

[jimrs2000]

Getting a coil this morning........watch this space.

[fintstone]

I have used a 6-pin Permatune (with a Bosch blue coil) for almost 10 years with no problems...it was installed by one of the best shops in the business who had no problem suggesting I use one when I swapped from a 2.7 to a hot rod 3.0L. Seems like a pretty darned good product to me...especially considering the price difference.

[jimrs2000]

Coil fixed it!!!

[Lorenfb]

"Seems like a pretty darned good product to me...especially considering the price difference."

Huh? Price difference? And the purchase of another coil versus keeping the small
original Bosch black coil that basically never fails. Where's the logic there?

[Lorenfb]

"Coil fixed it!!!"

Good! Hopefully the failed coil was not a silver Bosch coil. As they are very unreliable
as has been posted many times here on Pelican. If so, troubleshooting time was wasted.

[Perma-Tune]

Good for you!

Loren,

I believe fintstone is talking about the OE price vs. Perma-Tune.

[Lorenfb]

"I believe fintstone is talking about the OE price"

The OE price is a joke! Only the super naive consider that as an option.