WonByOne

I just bought a used 1999 996 3.4 Carrera 4. I did not get records or have a ppi since I flew in and had to make a quick decision. Well, I'm an impolsive idiot (I know), but rather than discuss "feelings" I'm looking for practical advice on fixing the problem. Here's what I know so far and will have time later today to get in and pull things apart. There is a ticking sound in engine that is most noticible at idle. There is also a bit of white smoke, mainly at startup. Below are two videos showing these too issues. There's also a CEL that reads: p1117, p0139 and p0102. The owner said it through codes due to custom exhaust. Thinking the best of humanity, I believed him. He also "said" that IMS was done at 70k along with other upgrades like intake, body kit, suspension. But who knows...
oil level is roughly 2 mm above lower notch of dipstick, within the normal cylinder. Any help from those who know the car is much appreciated.
https://youtu.be/zLtAflKljuQ
https://youtu.be/PuTCjVNbic4

WonByOne

Here's white white video.

kondata17

I'm gonna take a wild guess that this was the c4 from the Internet Car Lot in Omaha? Sounds to me like either a bad lifter (which is probable) or possibly scored cylinder walls. Mine smoked a little on start up as well, if it goes away, thats probably normal. The codes seem to be oxygen sensor related. How does the car drive?

WonByOne

Ha! Wow you are observant. Yeah, it's that car. I LOVE the car so no complaints there. The car drives wonderfully, just amazing actually. But I feel like I just rescued a dog and trying to determine it's history based on it's personality. I am just so scared of that bore scoring and something catastrophic, but I drove it 600 miles and zero issues other than tick sound and this smoke. If I can somehow know it's nothing catastrophic, I'm elated with the purchase. But I don't trust mechanics so I don't want to bring it in. More than likely they'll just tell me to spend more money than I can afford and it will be wrong. Mechanics have swindled me before, that's why I do all the work on my cars.
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pcasanova

Take it to a respected Indy that knows these cars. Smoke during startup could be many things including oil has been overfilled. Ticking could be Lifter / Scored Cylinder walls / Exhaust Leak, etc.

My 02 C4 was throwing similar codes referencing O2, running rich, etc, at the end it was a loose vacuum line.

Let them confirm the problem and take it from there.

cds72911

I'm with pcasanova - get it looked at by an independent shop. With any used car, I'd also baseline fluids and filters before you start putting the miles on it.

WonByOne

How did you know what car this is? You are observant! I just sent a reply but for some reason I don't see it showing up here. Car runs great, really an amazing car--love it! But I'm also apprehensive and the wife is stressed since she doesn't care about cars, so I'm battling my fear of something catastrophic with the engine (based on all the posts regarding bore scoring, etc) and trying to assure the wife that we got a good deal on the car. Lol...probably the issue with many Porsche owners.

WonByOne

Ill do that today. I'm also going to call around to shops where the car fax report shows it was owned, see if I can track done some service records on the car.

WonByOne

Should I also swap out the water pump? The miles are near 90k, and it seems like that is a 30k maintenance schedule? Also planning on new plugs. Anything else?

TexSquirrel

cds72911

Code P0102 is mass airflow sensor, air mass below limit. Make sure MAF is plugged in, no short circuit to ground, or your MAF is bad, and replace your air filter element.

[I got the wrong code - ignore this - Code P0117 is type 2 or type 3 engine temperature (coolant) sensor. Open circuit or below limit. This sensor is in the bottom of the coolant overflow tank.]

TexSquirrel is right, P1117 is the O2 sensor heating circuit in bank 1. Could be too high, too low, open circuit, too high resistance. You need to troubleshoot.

Code P0139 is bank 1 o2 sensor after catalyst. Implausible signal from o2 sensor. Could be the aftermarket exhaust, or could be a shot o2 sensor. Probably the same as the above.

You'll want a manual - Bentley is good, Alldata is my newest find (thanks to another Rennlister) - subscription based, but great info.

TexSquirrel

I would.

cds72911

You'll never enjoy a 996 if you let it stress you out. Put the worry beads away. It's just a car, and everything is fixable. Maybe start with reading the FAQ, digging into the forum and reading a lot, buying a few books - Bentley is a decent shop manual. The Wayne Dempsey 101 projects book will give you lots of ideas. Adrian Streather's 996 Essential Companion is also a good reference/read. It'll be fine.

TexSquirrel

+1

I also second having someone who truly knows the M96 look and listen to it.(and bore scope it)
I listened to the video, and it does sound like a lifter, but according to The expert on these engines, many times bore scoring is misdiagnosed as a bad lifter.

Paul Waterloo

Does the engine tick like it does in the video after it is completely warmed up? Or does it change? If so, what does it sound like cold and then again warm?