23 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHAcceleration to redline is not smooth
Reported or suspected cause
mass air flow sensor
Reported cause
No successful repair reported for this finding.
1
Identified cause
0
Suspected cause
0
Reported fixes
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Reported cause
The check engine light then came on, and the mechanic told me that it was the mass air flow sensor that needed to be replaced.
Leading evidence: 'mass air flow sensor' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'mass air flow sensor' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Adjust but i am not sure' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
And assuming the 996 change for the 3.6L is similiar to the change made for the '03 Boxsters the amount the timing can be changed was increased.
Replace lift while the original variocam could only
Suggestion or failed attempt
No successful repair reported for this finding.
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Unsuccessful attempts
1
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Suggestion
I believe the difference is the Plus version can change lift while the original Variocam could only change timing.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Suggestion
And assuming the 996 change for the 3.6L is similiar to the change made for the '03 Boxsters the amount the timing can be changed was increased.
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23 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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2 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
I fixed it.......More like I caused it and THEN fixed it.
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I fixed it.......More like I caused it and THEN fixed it.
When I modified my airbox to remove the resonator (you know, the closed box hooked to the tube just ABOVE the MAF) I did not block it off. Thus the engine was taking in air PAST the MAF causing issues.
I should have known better but missed it. OOPS! Live and learn.
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Well, this evening I pushed the PCar hard against another car
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But what I noticed was the power was not smooth thru the acceleration. The best way I can explain it was a surge or loss of power momentarily at several points during acceleration. THis was in every gear.
I have a B&M Air filter in the car. But that is all.
The car came from NY to Denver. Thus a 5280ft gain. I know is SHOULD adjust but I am not sure.
Any suggestions?
Thanks.
Variocam can deliver these symptoms sometimes, however, I have noticed this only on moderate acceleration thru the gears, not during WOT.
Just my $0.02.
I think the more you read, the more you will hear this complaint. I've seen many posts of the like and too have experienced the same dips and surges in acceleration. The car is still fast as F#$% though, right?
My 996 is smooth and very linear. It is an 04 though with only 1,600 + miles on it. I have felt surge areas in the TT. Not bad, but a few here and there even after lag.
I had lags here and there in my 964 until I got the top end rebuilt . . .
Recently I experienced a similar scenario where the car felt like it didn't want to push at around 5K RPM. The check engine light then came on, and the mechanic told me that it was the mass air flow sensor that needed to be replaced.
Sure enough, after the job was done (and a couple of days for it to regulate itself), the car accelerated like it did when I first got it.
I really do not hink it is the limiter. It is happening way before that. It is just odd.
I had to replace the battery the other day and thus had power off the ECU for a while. To my understanding that should have reset any adaptive values. But that is based on my BMW knowledge.
I don't think the '99s had Variocam. I believe it was introduced in '02. I had a '99 C2 cab and traded it in for an '02 and there is a difference. With the '02 there is a little bit of a surge at about 3,200 rpm.
The '99s had Variocam, it's Variocam Plus that was added for the '02 models. I believe the difference is the Plus version can change lift while the original Variocam could only change timing. And assuming the 996 change for the 3.6L is similiar to the change made for the '03 Boxsters the amount the timing can be changed was increased.
On WOT, there should be NO surges or hesitation. If you go WOT, you should come close to redline before you upshift. The next gear then will still have the revs fall on the power band of the Variocam. Hence, there should be no variation, and no surges or hesitation, since the variocam will not change. I'd have the car checked. It may be a fuel delivery problem or an ignition problem. It certainly is not normal.
going on mercedes experience i believe you need to look at the mas......especialy if you run non stock air filter. merc owners with k&n had some eary failures with mas systems.
