wilson234

Purchased a 2007 turbo with 14k miles, have put on 3k miles over the last 2 months and have no regrets. One thing I noticed is when the car is cold (relative as I'm in southern California) it will lurch starting around 4k rpm. Meaning if I am lightly on the gas gaining rpm, the fueling seems off starting around 4k rpm, runs rough which can cause the car to lurch forward then power delivery lets off and then back on, causing a slight lurching feel. Once the car is up to operating temp, no issues with lurching. Just curious if others have similar experience, or if any suggestions on what it could be.

Also, I notice the passenger seat shakes quite a bit at freeway speeds ( no passenger), but also figure this is normal?

Any feedback is appreciated.

Zeus993

Hey Wilson - I've no data on what this could be. The did run across my mind that the 4000 rpm lurch you are experiencing is from the turbos kicking in! But I am sure you know that. . Sorry I can't help out. Hang in here and someone with more knowledge will post.

As for the passenger seat shaking, I would check under the seat. I had the strangest 'rattle' coming Fromm the passenger seat and was imagining all kinds of expensive repairs and it turned out to be a golf ball rolling around. Goofy. Simple fix. Wheel balance?

Coupe or cab? My cab definately squeaks more than my past coupe.

Macster

Well, IIRC Porsche advises not exceeding 4K rpms until the engine is warmed up, and yet you are exceeding 4K rpms with the not warmed up.

So, stop doing that.

As for the seat do you feel any vibration through the steering wheel?

The tires may be out of balance. Even if they were in balance at some point as the tires wear they can lose balance (as the tread density is not 100% uniform) and have to be rebalanced if the out of balance condition becomes intolerable.

phillipj

That is not normal.. You should have a tech see if he can read any codes. If you have a realationship with a Porsche tech he shouldn't charge you to do this... Where are you in So Cal? I'm in Pasadena. If you are nearby I have a great shop for you..

wilson234

When I purchased the car had a ppi performed, and there was no mention of any error codes. I'm in orange county.

Again the lurching occurs until the car warms up, I guess I'll keep it under 4k till oil is up to temp.

Thanks for the input!

Macster

Just so it is clear that I'm taking your post seriously, you are really doing something I almost never do and then when I do do it I do it by accident. Well, from just not paying as close attention to my driving as I should.

Also, the breach of the 4K rpm threshold with a cold (or even a cool engine) is not a large one just over 4K and concurrent with the realization is it happening I'm focused on getting my foot off the gas and not on how the engine reacts at least at the breach time. I certainly do focus on how the engine is running after, that it is not making any scary noises after.

Then as punishment I mentally kick myself for not adhering to proper cold engine driving.

As much as I like to help fellow Porsche owners I'm not about to subject my cars to this treatment. They being different models could react differently anyhow even if I could bring myself to subject my cars to what I would consider, well, mistreatment.

All I can say is absent any CEL, absent any other signs of engine trouble, and without knowing the severity of the symptom you are complaining about this is imho a self inflicted problem.

Oh, I assume the oil in the engine is reasonably fresh and of the right type and viscosity. Remember these engines have very sophisticated variable valve timing and lift systems that operate when cold and that of course are very dependent upon the oil for their proper operation.

But you are certainly free to speak to a pro tech and get his feedback. If he says OMG you are reving the engine too high with the engine temp too cold (oil temp is cold too remember) then you know.

But he could say that's not right and then cover some other things that can be done to try to get to the bottom of what then is not normal behavior.