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Do you believe (or know) that stock stereo is a known drain when parked for extended period?
not the radio per se. but for whatever reason, these cars have an incredibly high parasitic drain while simply being parked. could be the inside alarm remote sensor ( which can be shut off by double clicking your key fob until you hear it "beep" ).
but whatever the cause? most all of us have trickle chargers and leave them plugged in for any extended period of time. i recommend the cheap little ctek 3300. its like 60 bucks has a cig lighter adapter and also the alligator clips - and is the same unit porsche uses as their "branded" trickler.
it ( or one similar ) is a "must have". trust me lol
The ECU and various sensors on the car draw a good bit of current. Besides a battery tender double locking the car, hitting the lock button on the fob twice so the horn honks and the lights flash, puts the ECU and sensors into "sleep" mode and less current is drawn.
Update: I charged the battery for hours this afternoon, then cleared all the codes from yesterday, then drove for an hour, checking out various aspects of the car. Weak boost is still there, if not worse, and the car idles rough and dies often at idle.
Here are the fault codes present after tonight’s test drive:
I have not been able to pick up parts for boost leak test, but hope to do so tomorrow. Any observations regarding the persistent fault codes, and PSM/ABS warnings? Also I noticed while driving that the red perimeter lighting around the after-market Alpine radio is flickering, generally about 1Hz, but inconsistent in actual frequency. I wonder if that suggests an electrical problem. Also, I grabbed a few screens in Durametric after the test drive. Pasted here, though I confess I am guessing which fields might be helpful in ID'ing the root cause here.
I welcome any insights. I am happy to log data if that's likely to be more effective.
(engine stalled at the end of this sampling session)
I strongly prefer boost pressure testing at the intercooler inlets vs. the airbox. It will identify the key leaks quickly and without chasing the phantom leaks that you will get from airbox pressurization.
You can build your own pressure testers in about 15 minutes with about $8 worth of supplies with two 1.5" schedule 40 PVC plugs and a 1/8" NPT tank valve. More info here
I think you need to start removing variables. When I first got my car, on the advice of several tuners, I started with fresh plugs, fresh coils, and a fresh fuel filter. If you have any sort of aftermarket air filter, replace it with an OEM paper filter. If you have any sort of aftermarket air intake, try and source a stock airbox. I know you said some of this work was already done, but I wouldn't necessarily trust it was done right. Check it all yourself. You'll probably find and fix the loose heat shield along the way.
But that aside, first thing I would do in your situation is to do a mechanical boost leak check. Critical on these cars.
You definitely have low boost, but I'm not sure if you can determine at this point if you have low boost because your car is going in limp mode or you have leaks. Build (or buy) the test plugs and TEST for boost leaks mechanically instead of trying to figure out a potential mechanical problem with a diagnostic computer and data logging. Boost leak testing is very easy to do... Now sometimes finding the leaks and fixing them isn't so easy, but you can tell in 15 minutes of testing if you have a significant boost leak or not.
After that, you can start troubleshooting other issues like a dirty or bad MAF, fuel issues, etc. It sounds like a bad MAF is a good possibility, but they are a bit pricey to just swap in to see. As mentioned earlier, try running with the MAF disconnected and see how it drives. If you do replace the MAF, many report having problems with anything but an OEM Bosch replacement. I think the Bosch part number is 0280218009
Also, my car also has a very high parasitic drain if the key is left in the ignition, even if fully off. Will kill the battery in a day or two. Simply removing the key and leaving it on the dash or floor and there is very little parasitic drain, no worries for weeks or even months.
Also, my car also has a very high parasitic drain if the key is left in the ignition, even if fully off. Will kill the battery in a day or two. Simply removing the key and leaving it on the dash or floor and there is very little parasitic drain...
Are there people who leave the key in the ignition when the car is at their home?
I think you need to start removing variables. When I first got my car, on the advice of several tuners, I started with fresh plugs, fresh coils, and a fresh fuel filter. If you have any sort of aftermarket air filter, replace it with an OEM paper filter. If you have any sort of aftermarket air intake, try and source a stock airbox. I know you said some of this work was already done, but I wouldn't necessarily trust it was done right. Check it all yourself. You'll probably find and fix the loose heat shield along the way. But that aside, first thing I would do in your situation is to do a mechanical boost leak check. Critical on these cars.
You definitely have low boost, but I'm not sure if you can determine at this point if you have low boost because your car is going in limp mode or you have leaks. Build (or buy) the test plugs and TEST for boost leaks mechanically instead of trying to figure out a potential mechanical problem with a diagnostic computer and data logging. Boost leak testing is very easy to do... Now sometimes finding the leaks and fixing them isn't so easy, but you can tell in 15 minutes of testing if you have a significant boost leak or not.
After that, you can start troubleshooting other issues like a dirty or bad MAF, fuel issues, etc. It sounds like a bad MAF is a good possibility, but they are a bit pricey to just swap in to see. As mentioned earlier, try running with the MAF disconnected and see how it drives. If you do replace the MAF, many report having problems with anything but an OEM Bosch replacement. I think the Bosch part number is 0280218009
Thanks @pfbz ! Your thread on building and using leak test gear is very helpful. Heading down that path today, hardware availability permitting. Another local rennlister has a spare MAF sensor he's offered as part of the debug process, so hoping to attack both in parallel. As to your other questions, the entire car is stock-stock-stock other than after-market Alpine radio, and short shifter installed by original dealer in 2001. Paper filter, OEM air box, OEM exhaust, etc. So nothing after-market to pull out of the engine bay.
Since it's at least as much about the journey (debug, fix, repeat), as much as the destination (a fully solved 996TT), I appreciate the collective expertise of the tribe here, whether it's MAF part #'s, double-locking keys, or roughing up a fitting so it doesn't blow off at 30psi. Thanks all!
PS: one ray of sunshine in last night's test drive: I confirmed precise location of roof rattle, and think I can get to it from sunroof tilted, without having to drop headliner. Fingers crossed.
Are there people who leave the key in the ignition when the car is at their home?
I lived for years in the mountains, front door never locked, keys in ignition of everything that had an engine inside or out of a garage or barn, never thought twice about it. And needless to say never had a problem, though it was more than a few years ago. Mountain neighbors are pretty attentive of strangers lurking about.
I'm closer to town these days, but the Turbo key would still be in the ignition when in the garage if it wasn't for the parasitic drain problem. My property is pretty secure.
... or roughing up a fitting so it doesn't blow off at 30psi....
I know you likely didn't mean this literally, but *do not* go up to 30 psi when pressure testing your turbo plumbing! 1 Bar is plenty for finding most leaks and really no reason to even think about going over 1.3 Bar unless you are running some highly modified setup.
04-02-2020, 08:13 PM
