I am Stuck, Replaced the CDI & Coil & Still No Spark!

[Vincent Hill]

Originally Posted by john walker's workshop

and now you have a heated seat to boot.

I must not be praying "Enough" for you! At least my wife always wanted heated seats!

[Ken911]

there are still a few places that have them in stock and you can find them on e bay still. Hopefully it's only the wire. As burnt and dicolored as it is that's about a 90 percent chance. Oh make sure before you pull the distributor out the engine is at TDC and the rotor pointing at number one cylinder.

[Vincent Hill]

Originally Posted by Ken911

there are still a few places that have them in stock and you can find them on e bay still. Hopefully it's only the wire. As burnt and dicolored as it is that's about a 90 percent chance. Oh make sure before you pull the distributor out the engine is at TDC and the rotor pointing at number one cylinder.

Thanks for the warning on the Distributor! WHen they are NOT a slot but gear, timing is real easy to mess up! Please do not ask me how I know this so well!

I think I will try to find the part now even if I do not need it. "It is Better to have and not need than to Need and not have!"

[Bob Kontak]

I think you can still get them if yours is bad. I have one in my tool box if you need it. I bought mine at O'Rielly's in Houston a few years back

[Bob Kontak]

Here it is

[Bob Kontak]

Parts Geek has them.

[Vincent Hill]

Originally Posted by Bob Kontak

Parts Geek has them.

As Usual, U da Man I am on it right now!!

Bought for $52 including SHipping! Just following your lead.

[RoninLB]

Originally Posted by Vincent Hill

it will be 1/4 to 3/8" off the floor for Airflow all around.

test fit with your seat installed

[Vincent Hill]

Originally Posted by RoninLB

test fit with your seat installed

AMEN!! I never removed it! I slid it as far forward as possible and then put the unit so that everything could be reached directly. My hand is my Guide, If I cannot get my hand over the unit then it is too high, My hope is that I have 3/8" under it and at least 1" over it. I will adjust until I have more space over than under for the best possible airflow.


The wire should be here tomorrow and hopefully the weather will be cooler on Thursday and I will pull the Distributor and Mount the Wire and see if that resolves it. If not, then I will install the Distributor Coil and check again.

I know not to install both at the same time because then no one will now which was the problem. More work but more knowledge. I will post again when this is done because NOTHING Irks me more than for someone to have a problem and everyone posts suggestions and then we never hear from them again!

[Bob Kontak]

Here is my set up. No problems seven years. Well, to be honest, the tach wire comes loose occasionally on the gauge itself.

[Vincent Hill]

Clean floor! Mine is back about 8 to 10 inches and mounted to Both sides of that Bar that runs across the entire floor. I also drilled a Hole in the inspection Cover and ran the wires Under the Carpet into the cover. Your unit looks a little different than mine. I have a Plug on 1 side and nothing on the other. SInce I wantged to have Carpet, I carefully cut out the 4 holes in the rear piece and then the Carpet Mat so that the unit sits Above all od these pieces on the Rubber anti vibration mounts. You have a Targa?

[Bob Kontak]

YEs Targa. I may not have the digital one;

[Vincent Hill]

Originally Posted by Bob Kontak

YEs Targa. I may not have the digital one;

[Bob Kontak]

I ran the ground to the transmission ground lug., I put the wires under the carpet and rear seats and drilled a hole in the back wall and used grommets.

I wish I would have put the grommets closer to the inner fender because when you open the hood "There they are" on the firewall

[Lorenfb]

"Mine is back about 8 to 10 inches and mounted to Both sides of that Bar that runs across the entire floor."

Not a good place to mount:

1. Potential water damage, i.e. lowest point in car and all 911s
leak especially the older they get,
2. A lot of vibrations there that are easily transmitted from the
road, and
3. Load wire runs cause voltage input drops and the output
spark signal (450 volts plus) can cause mis-fires and electrical
interference.

"so that the unit sits Above all od these pieces on the Rubber anti vibration mounts"

Makes for poor heat transfer. The unit will have better heat transfer mounted flat against
a steel substrate.

[Bob Kontak]

My box is mounted to plywood but on the vibration buffers in pic above. If I remember there is a piece of steel that is welded to the floor but flexible - like a tab but wide enough to get two bolts in it. Keeps it away from water and the whole unit can flex up and down a little.

lorenfb - can you talk a little more about point #3. I don't understand it but would like to correct any issues if I have them/

[Lorenfb]

"Long wire runs cause voltage input drops and the output
spark signal (450 volts plus) can cause mis-fires and electrical
interference."

1. The MSD inverter draws a fair amount of current which can result
in an input voltage less the desirable if an improper gauge wire is used.
2. The long run of the coil switching voltage (+450) can interfere
with the trigger signal, tach wire or other electronics, e.g. voltage
regulators.

[Vincent Hill]

Originally Posted by Lorenfb

"Long wire runs cause voltage input drops and the output
spark signal (450 volts plus) can cause mis-fires and electrical
interference."

1. The MSD inverter draws a fair amount of current which can result
in an input voltage less the desirable if an improper gauge wire is used.
2. The long run of the coil switching voltage (+450) can interfere
with the trigger signal, tach wire or other electronics, e.g. voltage
regulators.

Agreed about "LONG Wires"! My Longest is no longer than the longest Violet & (I do not remember other color) but it was in a Separate casing with 2 prong connectors at each end. From Actually reading the instructions I "Still" went 1 size larger in wire for the 18 inches I had to extend the other 4 wires. The Large Red and Black wires were not extended at all. SO I really only needed to extend 4 wires and no longer than 2 of the existing wires.

Second about Water and the Low point! Yes, when they do leak, the rear seat floor pan is where some of the water collects. Remember, I used the anti vibration mounts that are somewhere between 1/2 and 3/4" High and the Carpet and rear mat was cut out to fit around these mounts and I am extending the height another 3/8" above that to give a good space between the carpet and the Unit for AIr FLow.

There are drain holes in the rear floor that I have plugged most of them with the Plastic Plugs except 1. I would think that If I had a Severe leak or left the window down that between the drain Hole and the absorption of the carpet, I would HOPE that the water level would not raise above 1 inch! Remember mounted under the other seat there is the ECU for the O2 sensor as seen in Bob's Pic. SO if it was a REAL Bad idea then let us hope that Porsche thought it all out first and still mounted it under the seat.

[Lorenfb]

"I would HOPE that the water level would not raise above 1 inch! Remember mounted under the other seat there is the ECU for the O2 sensor as seen in Bob's Pic. SO if it was a REAL Bad idea then let us hope that Porsche thought it all out first and still mounted it under the seat."

Ask some of the 911SC (Targa/Cabrio) owners that had to buy replacement Lambda
ECUs the results of water damage. Then ask the 911 3.2 owners that had to replace
their DME ECM because of a non-repairable water damage. And how about the Boxster
and 996 owners that frequently replace the immobilizer ECU unit under the drivers seat
that gets flooded because of plugged water drains at about $500 each.

Don't think Porsche really thought too much on the location of electronics over the years!

[Vincent Hill]

Originally Posted by Lorenfb

"I would HOPE that the water level would not raise above 1 inch! Remember mounted under the other seat there is the ECU for the O2 sensor as seen in Bob's Pic. SO if it was a REAL Bad idea then let us hope that Porsche thought it all out first and still mounted it under the seat."

Ask some of the 911SC (Targa/Cabrio) owners that had to buy replacement Lambda
ECUs the results of water damage. Then ask the 911 3.2 owners that had to replace
their DME ECM because of a non-repairable water damage. And how about the Boxster
and 996 owners that frequently replace the immobilizer ECU unit under the drivers seat
that gets flooded because of plugged water drains at about $500 each.

Don't think Porsche really thought too much on the location of electronics over the years!

From the way you are writing, it seems more prone to have this happen on Targa's & Convertables. I have a Coupe. My thinking was to avoid Engine Compartment heat by installing it there. Now my question is, being safer from the heat vs possible water damage. I KNOW that it will get damaged from the engine heat and it is "Possible" to get damaged from water. I think for now, I will keep it where it is and if I ever get water there my Plan B will be to mount it on the Tunnel Hump where if it gets wet there I have a lot more problems than water

Now having this in the back of our minds we can a lot better look out for keeping this from being a problem. Also you have now made a Point for me that Porsche does not always have all of the answers or do everything in the best possible manner.