Steve Which one of these relays is the one controlling the Frequency Valve on the 328? Image Unavailable, Please Login
New ignition wires, new plugs, run for a few hundred miles and then misfires. unplugging one wire at a time does not indicate which cylinder misses. putting a timing light on each wire at a time shows spark at all 8 plugs ! No buzzing at the frequency valve. so, it must be that relay.
The frequency valve is a fuel delivery thing. Misfires would be an ignition thing. I would check your crank sensors.
But that is the problem, I am not sure it is misfiring. It may just be running like crap even with sparks at all 8 cylinders.
You are correct. I had a similar problem with my Mondial 3.2 and it was that relay that was bunk. I opened mine up and jumped the connections for test purposes to prove my theory. Now I have a special "test tool". I believe it is a part that is used on the Porsche 928 and is cheaper if you get it through Porsche or an independent foreign car parts place.
Found the problem. Relay removed from car, in hand. 10A fuse is good. But, measurement between terminals 30 and 31 give infinite ohms. The circuit inside must be toast. Time to open her up. Copter, you got a pm.
Here is the whole lambda circuit FWIW. There are several threads about reworking the module under the fuse. This one has substantial 'Steve' input: http://www.ferrarichat.com/forum/showthread.php?t=257920 This too: http://ferrarichat.com/forum/showthread.php?t=110147 New module $140 http://www.ricambiamerica.com/product_info.php?products_id=229521 Did you put the fuse back in when measuring infinity between pins 30 and 31? Prior to 328, the lambda qv's protection module had a fusible link internal instead of a fuse socket at the top. Image Unavailable, Please Login
Bad relay confirmed. 12V applied to pin 30, grd to pin 31, and 12V to pin 15 but no click was heard. Then clicks, and then nothing. So, it's toast. The coil is probably done for.
To close this thread out. It was the relay that was bad. It tested bad on the bench by intermittently connecting and then failed. Replaced one from Porsche (only because it is available locally) and it worked. The low lumbering power is gone, replaced with instantaneous power responding to the foot. And the buzzing noise comes back in the engine bay which means the frequency valve is working again.
Curious what the price was and if you still have the box, what is the part number? This comes up often enough the next guy will appreciate the info.
There's one that comes out of a 928 (believe it's the power relay for the ABS) that's a workable substitute. But, at $140 bucks the one from ricambi isn't that much more expensive. That relay seems to have a fairly high failure rate - have replaced a couple of those (my 3.2 mondial, my neighbor's 328) in just the last year. I took apart the old one for my mondi and it was just a matter of dirty contacts (so I have a spare).
+1 -- does it have the 10A fuse built-in or did you have to add a 10A fuse between the wire usually connected to terminal 30 and terminal 30?
Picture says a thousand words. $102 plus tax, and part number is on the box. And it does have a 10A built in but in a more integrated way than the Ferrari one. Those Germans, they do it right. Steve, you stayed quiet all this time? Image Unavailable, Please Login
Only because I didn't see this thread until you had already posted "Bad relay confirmed..." -- couldn't add anything useful to what you had already confirmed