PorscheTX928

Ok...I will try to give as much info as possible. I have a 1999 Carrera 996 with 85K, car died on me at a red light and would not restart. CEL had been on for a few weeks, but the car ran fine. The car died on me at a red light
on the way home and would not restart. It cranks fine, but does not seem to be getting fuel? I finally got around to pulling the codes and am getting 6...all fuel injector short faults for all six cylinders (P1225, P1226, P1227,
P1228, P1229, and P1230). I cleared the codes and the scanner confirmed the cleared codes, and I tried to start again....and all 6 codes came back. I assume that not all 6 injectors went bad at once, so what could the issue be? I replaced the CPS sensor, but that did not make any difference. I did a search for the codes, but nothing seems to relate to my issue since most references just refer to misfiring and poor running condition....my problem is
a crank with no start. Thanks in advance for any and all help or suggestions.

Porschetech3

Check fuse C1 in the fuse panel in drivers footwell. It supplys 12v to injectors, also to MAF and Vario-Cam solenoids . I have seen the Vario-Cam solenoids short and blow fuse causing no start. IF the fuse is blown, replace fuse and unpulg Vario-Cam solenoids and it will run. then OHM test solenoids.

PorscheTX928

Thanks for the info, Porschetech...and for those that might read this after, it actually was C2 that was blown...I put a new fuse in it and tried to start, and it started to fire, but then the fuse blew again.
I guess I have narrowed it down to being the problem...but what could be causing the fuse to blow? Where should I start? You mention the vario cam solenoids...where are these located? how many, and is there a way to
test them? Oh, wait, I guess this is where I should go back to the search function...Ill do a search for the solenoids. Thank you very much...I had checked the fuses, or so i thought and replaced not thinking one would
instantly blow again...so I thought I had ruled out the fuses.

DBJoe996

C2 is a 30 AMP fuse that covers the ignition, fuel injection and O2 sensors. I would start by checking your ignition switch, or maybe just replacing it with a new one (just the electrical part for $30). After that I would check for a short on the O2 sensors and wiring.

dporto

If the car was garaged for an extended period of time be sure to check for rodent damage to wiring...

Porschetech3

There are 2 Vario-Cam solenoids protruding through each valve cover at the timing chain area. the wiring connectors are located above the scavenge pumps in a holder. Bank 1 Drivers side is at the flywheel end, and bank 2 Passenger side is at the crank pulley end. You can test with OHM meter and also actuate with a 9v battery, there is a good test thread if you search. The connectors are not the easyest thing to get to, but in my experience that would be the first thing I would check to eliminate that as the cause of the fuse blowing.

A quick and dirty test would be to simply disconnect the solenoids, then see if the engine runs without blowing fuses, then connect one solenoid at a time until the fuse blows again, then you will know which one is faulty. The valve cover has to be removed to replace the solenoid.

Noz1974

What about the crank sensor ?? It's easy replaced compared to the cam sensors, if this goes faulty you get no spark?? Worth checking it, located on left side of engine if looking from rear near the bellhousing close to the crank sensors, which can also be changed, it's the variocam solenoids that need the valve cover removing, I'm betting it's one of these

Chris(MA)

Good one, mine failed and had symptoms of no fuel pump or spark. Quite easy to replace; you can also check it with a multimeter, it goes open circuit when it fails.

Porschetech3

In the first post it looks like he has already replaced the crank sensor to no avail.

I'm still in the camp of the Vario-Cam solenoids short. The fuse that is blowing IIRC is the 12v power to almost everything on the engine that has 12v.... injectors, Maf, tank vent,coils, Vario-Cam ect. The reason I fell that the Vario-Cam solenoids are the cause, is about 10 years ago I had a problem car, that would blow that fuse intermittently (after hours of driving) and every thing would test fine in the shop. And that fuse on the wiring diagram went to EVERYTHING, so while it is a "hard fault" I would eliminate that first, before it can turn into an "intermittent fault".

PorscheTX928

thanks for the info....i think i saw the solenoid connection on driver side when i was under there changing out the cps sensor....figured it needed a change anyway since it looks like the original. i will try the "dirty" test
and see if one of them is casuing the issue...is this a difficult procedure to change out both solenoids? im thinking if one is bad it might be best to change out both. i guess i need to price thwm too.

Porschetech3

Yes the connector for the Vario-Cam solenoid on the drivers side is next to the connector for CPS. Yes the replacement of the solenoid is difficult/ time consuming, hence I would only replace the faulty one, may be years/never before the other one needs replacing.

PorscheTX928

I was surprised at how much these cost!!! 300-500 per side! For something that looks just like the CPS sensor...I havent been able to go get some 30 amp fuses yet, but figure I will try to start the
car unplugging one at a time....I will report once I figure out which one is causing the problem...or if unplugging both causes no difference.

dporto

I'm pretty sure you can get the solenoids for around $100 ea. (give or take a few bucks). If you find that one of the solenoids is bad, you'll have to remove the cam cover to change it. While you're in there, you should check your cam chain tensioner pads and if they show any wear or age (brown as opposed to cream colored) you should change them (they're only about $25 for a pair). When re-sealing the cam cover be VERY careful how much sealer you use (recommended is 1mm bead) - I learned this lesson the hard way... Good luck

ocfservice

Try disconnecting oxygen sensors. Heaters could be drawing too many amps.

PorscheTX928

So while checking wiring for rodent damage and loose connections, I came across a weak point in the 996's cooling system. See attached pics...while wiggling hoses, this hose connection
finished snapping off and coolant began flowing! After some searching I found that this part is very prone to failure (catostrophic) as was explained in AutoAtlanta. They have a replacement part
that uses aluminum connections instead of cheap plastic. I just thought I would post so that others could check their own connector - it could save you some frustration later. For now, I have to wait
to start on the original problem until I can get the repl connector back in place and the coolant topped off.

Someone mentioned a 30 dollar ignition part that could be the problem. Can I get the part number? I may as well replace it if it is prone to failure, and would this part cause the fuse to blow? I am thinking that this could be the cause as I have changed the fuse a couple of times, and the car does start, but only for a second, before the fuse pops...

Part with broken nips on both top and bottom, right hand side of part. REPL part is 6 bucks, I went with the upgraded part at 18 bucks.


This is pic of the two hoses the part connects, you can see the broken nipple left in the bottom piece, top looks the same!


Part # is 996.106.226.51....the upgraded aluminum nippled part is T99610622652


This is the upgraded part - T99610622652 .