[HyperM3]

I dont know whats going on but in the past month or so my car has been driving like garbage.

I havent made any changes in anything be it diverter valves, chip or intake(its all been the same for a while).

However when Im cruising in gear not only does it still do the "waa..waa"(my expression for it feeling like it slows down and speeds up over and over(like when people press the pedal off and on)), but now it will actually lurch. When I say lurch I mean that Ill be pressing on the gas and it will hesitate and then launch(while Im already moving).

This isnt something that only happens when the car is cold since it warms up very quickly in the recent 80+ degree weather. It happens when Im showing 240 on the oil temp gauge.

With the Attache I installed the switch to put it back to stock settings. Even when on the stock map I still get this lurching and "waa...waa" annoyance.

I have no idea what to do but its extremely uncomfortable to drive and embarrassing when I have passengers in the car. Cruising at 65mpg on the highway I see peoples heads nod forward and back from the movement of the car slowing and speeding up. This happens when the foot is virtually applying no pressure on the pedal. I can also verify that something is happening from watching my boost gauge. It will go from -8 to -7 to -9 to -6 repeatedly when this situation is going on.

I dont know whats up but I dont like driving this car anymore. Anyone else experiencing this??

PS- Before anyone asks, I use the same gas from the same gas station all the time.

[NPDAN]

You know what bro, in the last few months it's happened to me a handful of time... I dismiss it even though I shouldnt... The 1st thought that pops in my mind when it happens to me is the freakin HPFP... I dont look at my boost gauge quick enough to see the action that may be happening.. I will next time though...

[HyperM3]

Originally Posted by NPDAN

You know what bro, in the last few months it's happened to me a handful of time... I dismiss it even though I shouldnt... The 1st thought that pops in my mind when it happens to me is the freakin HPFP... I dont look at my boost gauge quick enough to see the action that may be happening.. I will next time though...

This is what Im starting to worry about. Ive only got 13k on the clock and I thought I was past the point of where it would happen to me. Guess it can happen anytime. The last thing I want to do is have the HPFP go on me.

[NPDAN]

Originally Posted by HyperM3

This is what Im starting to worry about. Ive only got 13k on the clock and I thought I was past the point of where it would happen to me. Guess it can happen anytime. The last thing I want to do is have the HPFP go on me.

Yea seriously... I have just over 15k on it... I dont think we're ever safe until it's replaced...Even then who knows...

[.:bHd:.]

Originally Posted by HyperM3

This is what Im starting to worry about. Ive only got 13k on the clock and I thought I was past the point of where it would happen to me. Guess it can happen anytime. The last thing I want to do is have the HPFP go on me.

I have 20k miles and same thing was happening to me (bone stock).. I just had the fuel pump replaced after having the car die on me..no more lurching

[HyperM3]

Originally Posted by .:bHd:.

I have 20k miles and same thing was happening to me (bone stock).. I just had the fuel pump replaced after having the car die on me..no more lurching

So you were experiencing the exact same thing I am? I havent read this as a symptom before.

[.:bHd:.]

Originally Posted by HyperM3

So you were experiencing the exact same thing I am? I havent read this as a symptom before.

Yupp, it wasn't constant though and it was usually at slow speeds.. I havn't felt it since I got the new fuel pump so I'm guessing its from that.

[NPDAN]

FU@# were doomed!!!!

[StarrDlux]

so the car doesn't throw a fuel trim too low code when the pump is dying? or misfires?

odd.

[scottp999]

Just happend to me today. I thought my foot must have slipped (wearing sandals), but then I realized nothing was wrong with my foot placement and that the car had just gotten more fuel when I was pressing evenly (slow speed) on the accelerator.

[HyperM3]

Originally Posted by StarrDlux

so the car doesn't throw a fuel trim too low code when the pump is dying? or misfires?

odd.

Apparently not all the time.

[bimmermansfl]

Any updates on this?

Hyper,

Are you still seeing this?

[HyperM3]

Originally Posted by bimmermansfl

Any updates on this?

Hyper,

Are you still seeing this?

Yeah, still seeing it. Gonna reset my ECU tomorrow and see if it still happens. Spoke to my SA the other day and he said hes never had anyone complain about that before. Told me to make an appointment if I want to have them check it out. I was too lazy at the time but I think I will at some point.

[galahad05]

Originally Posted by HyperM3

Yeah, still seeing it. Gonna reset my ECU tomorrow and see if it still happens. Spoke to my SA the other day and he said hes never had anyone complain about that before. Told me to make an appointment if I want to have them check it out. I was too lazy at the time but I think I will at some point.

Auto or stick? If auto, it's possible that there's something going on there with the tranny. If a stick, then it's fuel/engine related.

For fuel/engine related possibilities, here's a bit of history:
In the good ol' days (carbuetors and multi-port FI) surging was sometimes related to carbon buildup on the throttle plates (either), bad fuel pump/semi-clogged fuel filter (either, but usually FI), carbon buildup on intake valves (either), partially clogged fuel injectors (FI--duh), incorrect float levels (carburetor), more rarely problems with ignition advance...
The above was by no means an exhaustive list of possible causes of surging.

[HyperM3]

Originally Posted by galahad05

Auto or stick? If auto, it's possible that there's something going on there with the tranny. If a stick, then it's fuel/engine related.

For fuel/engine related possibilities, here's a bit of history:
In the good ol' days (carbuetors and multi-port FI) surging was sometimes related to carbon buildup on the throttle plates (either), bad fuel pump/semi-clogged fuel filter (either, but usually FI), carbon buildup on intake valves (either), partially clogged fuel injectors (FI--duh), incorrect float levels (carburetor), more rarely problems with ignition advance...
The above was by no means an exhaustive list of possible causes of surging.

Its a manual. However, your theory could be onto something. In the past two months my commute went from about 100 miles a week to 10. I barely get the car up to temp by the time I arrive at work. I never drive it past 5kRPM and I hardly ever go WOT. Could just need to be blown out a bit I guess. Sounds like a good time to hit the track.

[galahad05]

Give it a shot, can't hurt. I knew some old-school porsche 911 owners who used to "blow out the carbon" every once in awhile. They claimed the company wanted them to do it via the owner's manual...

[bimmermansfl]

Sparkplugs?

[Andrew@ET]

MINE DOES THIS !! i have a 328 stick. to me it happens like once a month. yesterday after driving it hard all of a sudden when in 3rd gear at aroudn 4k it would start to go then stop then go making me bobble head like crazy. 1st and 2nd were good but 3-4 and -5 with doing this i tried turning off for a sec but it kept doing it . then i tried a 5 min rest then it drove fine. it does this at random times about 3 times in total in 14 k miles .

[nj335i]

I had my fuel pump replaced last fall and am getting the same symptoms as described here...

[nj335i]

Anyone get a slightly uneasy idle at startup too?

[HyperM3]

So I reset my ECU on monday. Filled it up with a full new tank of gas(last time I filled up was May 31). Unfortunately, its still happening. I just feel too lazy to bring it to the dealer right now.

[Tag]

I don't believe it's carbon build up, the car is too new. All symptoms sound HPFP related.