Advice needed about throttle/engine smoothness
04-28-2014, 03:37 PM
#16
Anyone happen to know which changeover valve controls the intake or engine vacuum system.
Without a code the dealer won't touch it with a barge pole.
Without a code the dealer won't touch it with a barge pole.
04-28-2014, 03:41 PM
#17
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04-28-2014, 05:39 PM
#18
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Except that there is plenty of debate on that point. I happen to side with Chuck in believing that the Motoman-type hard break-in (assuming oil is at proper operating temps) is a superior way to get the rings to seat fully.
In my experience with Audis, the folks who did the factory-recommended break-in always burned (a lot of) oil, and the folks who did the hard break-in never burned a drop.
In my experience with Audis, the folks who did the factory-recommended break-in always burned (a lot of) oil, and the folks who did the hard break-in never burned a drop.
04-28-2014, 06:07 PM
#19
Drifting
Except that there is plenty of debate on that point. I happen to side with Chuck in believing that the Motoman-type hard break-in (assuming oil is at proper operating temps) is a superior way to get the rings to seat fully. In my experience with Audis, the folks who did the factory-recommended break-in always burned (a lot of) oil, and the folks who did the hard break-in never burned a drop.
04-28-2014, 06:21 PM
#20
Nordschleife Master
And there goes another thread turning into the now famous " break in procedure ", " which oil is best ",with info from Bob the oil guy and the " Manual vs PDK " type of threads,where everyone has an opinion. And the guy that started this thread is not getting any good info this way...
Just sayin'...
Just sayin'...
04-28-2014, 06:36 PM
#21
Rennlist Member
I'm not sure I understand what good Techron or another fuel system cleaner will do in a direct-injection engine. Is it still useful for cleaning exhaust valves/seats?
You should absolutely look for a good independent shop for a second opinion, even on a brand-new car. The engines in the current cars are not that new. They have been on the road since 2009, and they will not be unfamiliar to the better indy techs. The independent shop should be able to offer some insight based on the parameters neanicu mentions such as LTFT/STFT and misfire counts. A dyno shop is an excellent suggestion.
Remember that the dealer gets paid to sell cars and fix them, while the indy only gets paid to fix them. Sometimes you'll run into dealer techs who are clueless if the computer doesn't tell them exactly what part to swap. Their next step is a fishing expedition, undertaken at someone else's expense (either the customer's or Porsche's.) Most independent shops can't afford to work that way.
As for Italian/German tuneups, they were all well and good back when ignition systems had as much power as your average carpet-versus-doorknob spark, but I'd be surprised if they are very helpful in the DFI era with coil-per-plug solid state ignition systems. Can't hurt to try, of course, as long as you're under warranty.
You should absolutely look for a good independent shop for a second opinion, even on a brand-new car. The engines in the current cars are not that new. They have been on the road since 2009, and they will not be unfamiliar to the better indy techs. The independent shop should be able to offer some insight based on the parameters neanicu mentions such as LTFT/STFT and misfire counts. A dyno shop is an excellent suggestion.
Remember that the dealer gets paid to sell cars and fix them, while the indy only gets paid to fix them. Sometimes you'll run into dealer techs who are clueless if the computer doesn't tell them exactly what part to swap. Their next step is a fishing expedition, undertaken at someone else's expense (either the customer's or Porsche's.) Most independent shops can't afford to work that way.
As for Italian/German tuneups, they were all well and good back when ignition systems had as much power as your average carpet-versus-doorknob spark, but I'd be surprised if they are very helpful in the DFI era with coil-per-plug solid state ignition systems. Can't hurt to try, of course, as long as you're under warranty.
04-29-2014, 05:49 AM
#23
Anyone? Anyone? Beuller?
04-29-2014, 06:24 AM
#24
If I could help you mate I would but I have too little knowledge on the subject. It does appear you have been subjected to some special treatment. Such is the way with forums I guess.
Peace to all.
Peace to all.
04-29-2014, 07:16 AM
#25
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3.4 engine here. 7MT. I've had an ongoing frustration with a lack of smooth running at certain RPMs, and a lack of smooth acceleration on light throttle through an RPM range. This is probably not related to the variable cam adjustment that happens around 3K RPM that has been discussed elsewhere. It almost feels like water in the fuel - that kind of subtle hesitation and stumbling. I have tried many types of gasoline to rule out particular gas formulations. I always use 93 octane. This has been going on for many, many months, but I think it's getting worse. I've taken it to the dealer twice now about this and each time they say no codes, so therefore it's "fine" and "normal". But this past weekend I reached the point where I wasn't even having fun driving my car. I was filled with worry about what's wrong, and just wanted to get home to get out. That's not good for anybody. So, my questions: 1) Should I go to an independent shop and get a second opinion? I just wonder if the independents have seen enough 991s to know, but I have no idea. 2) Does anyone have any tips on trying to rule things out myself? 3) Am I expecting too much? Should I not expect a smooth engine feel when cruising or accelerating? If that's the case, then I can adjust my mental picture. I just need to know if I'm out of line here. Thanks! I appreciate the helpful responses.
Problem solved for me
04-29-2014, 08:29 AM
#26
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The car was babied through the break-in procedure, so it is time to start wringing-it-out, as it was engineered to do. Get the oil good and warm find some nice, open country roads, hit sport plus and DRIVE IT for a couple hundred miles. Not only will it likely cure the ailment - you and the car will become much closer. Try that first. If it persists, resort to Techron or such.
The car is meant to be DRIVEN!
enjoy
The car is meant to be DRIVEN!
enjoy
04-29-2014, 08:39 AM
#27
Burning Brakes
Thread Starter
I'm trying to reconcile what you said in your first post- "I'm not an aggressive driver nor do I tend to let it get too high up in RPM. I know, I know, I need to try doing that" with what you are saying now, which is basically dismissing me as a crank for saying exactly what you already said yourself you know you need to do!
Anyone? Anyone? Beuller?
Anyone? Anyone? Beuller?
I'm sure you're an expert in these vehicles, but your delivery leaves much to be desired.
Thank you for your input and I will take it under advisement. I'm sorry I "dreadfully babied my poor car was during "break-in"", apparently. I should let Porsche know their factory recommendations are wrong.
Good day sir.
04-29-2014, 10:48 AM
#29
04-29-2014, 10:54 AM
#30
Drifting
And there goes another thread turning into the now famous " break in procedure ", " which oil is best ",with info from Bob the oil guy and the " Manual vs PDK " type of threads,where everyone has an opinion. And the guy that started this thread is not getting any good info this way...
Just sayin'...
Just sayin'...