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Opened up the distributor cap. Lots of soot on the receiving contacts. This was after spraying with electronic cleaner, which admittedly didn't do much.
If you don't mind... what did you pay for the new cables? They can be expensive but can vary widely...
Also I wouldn't be too afraid of running the new cables yourself. It is really not hard at all... and can be done without having to remove much of the tinware...
No problem - paid $374 out of the door. Still seems like way above inflation given one of the guys who did the DIY for running them paid in the mid-200's back in 2004, but it is what it is. My "made in W. Germany" cables are certainly ready for a recycling bin.
I considered DIY on them, but seems like a job I'd be happy to have someone else do. I'm generally of that mindset, but after having my distributor belt rebuilt, I'm scratching my head why my wrench didn't suggest new rotors and caps (see above!) as its basically impossible to access the bottom cap/rotor without removing the whole damn thing!
^^ I'm not 100% sure what the ask is, but I'm pretty sure the car has never been "chipped".
Also to add some mystery, after replacing the O2 sensor and one of the two distributor rotors, the car really tried to not CEL me; however after 5 minutes or so it went back to its old ways. Timing is even exactly the same at 25 seconds.
As an update, I've ordered new spark plug cables, spark plugs, coils, and distributor heads. Basically going to rebuild the entire backend of electronics and see if that gets me there. Wish me luck!
Total: $615 in parts. I also had my distributor belt replaced while I had some other work being done, which would likely have been another addition to the list above if the CEL was flashing.
Where did you buy your Bosch coils from? I had to go back and forth with Pelican on a couple coils I got from them. One was missing the copper connector for the secondary terminal.
And another the resistance for the secondary winding was not right.
I keep hearing that the quality of Bosch coils isn't what it used to be. I have a couple older coils as spares to the new ones I bought for my car when I was dealing with ignition problems.
Interesting; the symptoms don't correlate exactly but if things don't work out, will be the next on the list. Have an appointment with a local Porsche indie on Wednesday to do the wires and plugs.
I did replace the second rotor and the closer distributor cap tonight though. Took car for a quick drive, still CEL. I'm starting to really get convinced that the cables are the culprit especially when you see this:
All the nodes were clean except this one, which had significant residue.
Originally Posted by CBR786
Home / 964 Forum
Technical Bulletin T1/90 MAF Wiring Harness Mod
As you know these cars are prone to weird things ...electrically speaking
I would start with coils, connections at spark plugs and mist the plug wires with water from a spray bottle while motor is running and see if there is any arcing
Flashing CEL in most cars indicates a misfire
Agreed - mine has had a few electrical issues over the years. My mechanic solved a particularly tricky one by putting the car up on the lift while running and then turned off the lights so that he could identify the issue by seeing the arcing from a short circuit with the coils.
By the way, as you probably know, with electrical issues, the code that shows on the Bosch Hammer scanner tool isn't necessarily the actual issue. My car was doing the "ghost in the machine" flashing of all of the warning lights in the gauges and throwing a code for a hall sensor error and it turned out to be a corroded coil wire that was shorting.
^^ Didn't know that; but is it really true? One of the indies I spoke to nearby actually claimed that the reason I'm probably not picking up the issue is because I don't have the "factory" diagnostic tools. I spoke with Tore about it and he thinks that's rubbish. But basically, in the eyes of the Indie, the factory diagnostics are as good as you can get...
...but if true, makes me feel a lot better about spending $130 for Tore's tool vs. over 1K for a Hammer.
^^ Didn't know that; but is it really true? One of the indies I spoke to nearby actually claimed that the reason I'm probably not picking up the issue is because I don't have the "factory" diagnostic tools. I spoke with Tore about it and he thinks that's rubbish. But basically, in the eyes of the Indie, the factory diagnostics are as good as you can get...
...but if true, makes me feel a lot better about spending $130 for Tore's tool vs. over 1K for a Hammer.
Even if the codes are occasionally wrong because of a short circuit, the Hammer is still the best way to diagnose electrical issues in a 964. Otherwise you're just wasting time shooting in the dark.
It is surprising that there isn't a Hammer emulator by now that exactly relocates it's functions. It's pretty primitive technology by modern standards.
Edit: see this string from 2006- Rennlister "Pcar SBA"
made a homebrew emulator of the Hammer:
03-22-2017, 12:43 AM
