CmackG

I went to check the oil this morning while the engine was running/parked. I saw and heard arcing from the two ignition coil(?) wires running from the driver's side fender to the distributor cap. Is this normal? The car is a low mileage 89 C4.
If this isn't normal (I suspect not), what is the part number, and can I replace the wires myself? (Think so).....

Rob McConnell

Hi Craig

Had the same problem myself, on closer inspection i noticed that the ignition wire contact to the dist cap was slightly corroded. i ordered a new one about GBP20. Checked all other points and ok, checked dist cap for cracks and the rotor arm all ok.

Put the new ignition wire on last night and still arcs, so i wrapped a strip of electrical tape around the point on the dist cap and it seems to have solved the problem.

Would like to hear what others think on this subject.

regards Rob
91 C2 Cab

J-McDonald

My 91 C2 had a similar problem. It manifested itself by turning on every single warning light in gauges and putting the engine into "limp" mode. The mechanic traced it to corroded coil wires that created short circuits. The shorts resulted in an error code for the "hall sensor". Fortunately, the hall sensor (a $500 part) was fine and replacing the coil wires (around $30/each) did the trick-- problem solved.

Adrian

Dear Craig,
You have to head off and purchase yourself a full new set of leads. What you are seeing is a result of pure age not mileage. The parts catalogue only shows each individual cable part number not a complete set. I recommend you look for a set from from local Porsche stockist or trusted aftermarket supplier,
Ciao,
Adrian
911C4

PS: The Porsche part numbers are a little complicated. The top six leads are the same for all model years but some of the the lower six leads were changed in 1991 and 1992 and only the 1991 and 1992 part numbers are given.
#1 to #6 964 602 060 01-06
#7 to #12 964 602 060 11-16 (1991)
#7 -17 (1992)
#8 -18 (1992)
#11 -19 (1992)
A full 1992 set will fit no problems.

CmackG

I'm seeing $400+ for a set. Is this correct?

Jeff Curtis

That's correct!

Jeff Curtis

Craig, let me add to that by offering a quality aftermarket solution, Windward Performance is a Magnecore distributor. I have used these 8mm heli-core monsters on my last two Porsches, the last one I used two different sets, being that I eventually converted to an Electromotive HPV-1 ignition setup...requiring a different set of wires. In all THREE cases of purchasing a set of Magnecores from Windward, I would up with what I thought was a superior set of ignition wires, they really are impressive.

Remember, and I'm sure you realize this, being that we have twice the spark plugs of most 911s...we're going to pay twice the price!!

Bill Gregory

Magnecore doesn't offer a set of wires for our 964 engine. They told me that they haven't worked out the 3.6L spark plug connector. Maybe if enough of us ask, they'll figure there is a demand for their high quality wires. Their email is magnecor@magnecor.com

Jeff Curtis

Huh! Dan @Windward told me that they offered a set...oh well, figure Magnecore would know better than Dan!? I agree, maybe if enough of us ask, they'll make some sets, all they do is use the Porsche connectors on their other sets anyway.

Ade - C4 91

Hi Craig,

Just out of interest, JZMachtech in London sold me a set of replacement wires that they said were from the original manufacturer (??), they were quite a lot cheaper and seem to be identical to the factory ones. P charge about 500GBP, and these were around 300GBP. Having said that, they were still more than guys in the US pay for genuine ones from P.

BTW fitting them properly is a MAJOR Headache. Suggest you get someone else to do it when they are doing your next tappet adjustment.

Ade
91 C4

MelissaM

964 Folks,

It's not only the spark plug wires that are suspect, but the boot that attaches to the spark plug and the wires.

I had a crack in one of my spark plug boots that caused all sorts of intermittent problems:

-- sudden power loss/power on
-- occasionally stalling while idling
-- warning lights suddenly coming on
-- convertible top warning indicator flickering

The spark plug boots can be purchased separately from the spark plug wires, so they are worth checking.

Good luck!

-- Melissa

MelissaM

Another thing I forgot to mention is that there was a Technical Service Bulletin in March, 1992 that may help:

TSB #29201 Ignition Cables Chafe On Ground Strap

Basically the Ground Strap on the left hinge of the boot lid can come into contact with the ignition wires. You can secure the ground strap so it is on the side of the hinge rather than on the bottom.

Good luck!

-- Melissa

PS To see the list of TSB's, go to
Alldata TSB web site and choose the year and model of your particular car.

If you want to see the full description of the TSB, you need to sign up as a member -- something like $25/year for one car.

964Cab

Hey Melissa,

I thought I had my problem solved (sudden loss of high voltage to all 12 plugs at once). But the problem is back again. It's intermittent.

My next move is to change all 12 spark plugs. I already changed the caps and rotors and have installed a rebuilt twin dist from Porsche ($253 Hendricks Porcshe in NC).

I don't see or hear any arching but I'm hoping a new set of spark plug wires will cure the problem.

Thanks,

Patrick
'90 C4 Cab (USA)> 5spd.

BTW: My Porcshe Mech tried my DMe brain in a car in his worksop and it worked fine.

MelissaM

Patrick,

Don't just swap out the plug wires -- you also need to check the boots. It's a separate part, and much cheaper than the plug wires. Who knows -- you might spend the time and money to change the plug wires, and not solve your problem because it was one of the spark plug boots.

Good luck!

-- Melissa

964Cab

Hi Melissa,

Wouldn't a new $400 set of Bosch spark plug wires ahve new "boots" ? I'm not sure I know what you mean. Do you mean the "boot" that actually snaps onto the spark plug tip ?

Thanks,

Patrick