hey all, i searched around to see anyone else described something like this, couldn't really find anything

after starting the car in roughly -2C weather, it starts and idles fine, i let it idle for maybe a min, put it in drive, and it chugs... like choo-choo train chugging :D

i give it a little gas to pull away and it smooths out, but then if i come to a stop again before exiting the parking lot it chugs again.

is this an early sign of HPFP failure?

thanks!

 

would be my first guess, yup

 

yes

 

no cel or code?

 

At that temp, it sounds like it is just colds. These engines are cold natured.

 

but if its just the cold making it stutter one would think that the start and/or idle would be affected. Usually youll get a harsh idle. Doesnt sound like the 'cold-start' problem either especially since its a '10

 

yup. hpfp.

 

nope

thanks for the replies guys... my oil change is coming soon, i will mention this issue

 

My semi-studder issue may be what you have. In the morning not as cold here in FL) I start the car and back out of my driveway, put the car in drive and if I ever so slightly touch the gas it will seem to chug just a little. Now I usually give it just a little bit more gas and it drives just fine. I asked my SA this and he said it was normal and just fine. I think if it were a HPFP it would exhibit a loss of power at a higher RPM than idle and would happen more frequently and throw codes. It seems as if they god bad and take a dump, not just chug a little in the morning.

 

mine doesnt chug when it's cold, so I doubt it to be normal. runs like a car that needs warming up, but no chugging

 

I had similar problems with mine when the car finally stopped running and then needed a new high pressure fuel pump. At first it would start and idle just fine but chug after putting in gear and giving it some gas. Soon it was starting and idling rough and finally it wouldn't start and stay running at all.

I would take it to the dealership ASAP. Mine finally stopped in a parking lot 50 miles from the dealer.

Travis

 

This is the same problem I brought my 2010 MCS in for yesterday. They "haven't diagnosed the problem yet". To add though, as it started "chugging" and the needle was all over the place, it would just die after a few seconds of chugging. Very frustrating on a car with only 2400 miles!

 

So the dealer tells me it's a faulty oxygen sensor. They did tests on the HPFP and took gas samples - both came back fine.

Would it make sense that a bad O2 sensor would cause this??