Hello again,

I bought my wife a 2007 chevy spark and it has been causing me some headaches. This is not a dire problem per se, but it is annoying. I have been driving for 20 years but I feel anxious when starting this car from a complete stand-still when uphill, as the throttle has a slight lag. I gotta shove the throttle all the way in and it still barely responds in time to prevent the car from rolling backwards into the car behind me; I feel that I am about to choke it. My wife is just learning to drive and seeing as I am barely able to maneuver this crap myself, it will probably lead to an accident for her if I don't fix it.

Have read that this problem is fairly common on chevies, but still, a list of common faults are made rather than "a" (singular) common cause. I know the catalytic converter rattles and is loose in its space in the exhaust system, and this might upset the second emission contrlling O2 sensor in the system. I also read that the MAF sensor as well as other O2 sensor may cause this, as well as the gas pump.

Fuel injectors are new, gas filter is new and air filter is new. Throttle body as clean as it can be.

Any clues on where to start / approach would be much appreciated. I am hoping to avoid changing a lot of parts "in the blind", ie. without knowing for sure. We already connected the diagnostic device and there are no fault codes.

EDIT: This is just a 4x1000cc engine, and I am starting to suspect that the underpowered engine is what's really causing this problem and not real throttle lag. The more people inside and the steeper the hill, the worse it is.

 

On a hill, use the "military style" technique. Hold the brake down with your left foot and hit the gas-pedal up some to rev the engine up when your going to move. If you have a hand activated parking brake, you could use that to not roll back. Just hit the gas and realize the parking brake They used to sell an attachment so the brake pedal is larger to the left, making it easier to do. Some/many vehicles came built that way,.but not anymore.
I think my old Chevy Nova had the leftward extended brake pedal.

 

Thanks, Henry!

Yes, I was thinking that I will have to teach my girlfriend to use the hand brake when doing uphill starts; there's no other way as it is really difficult to start on steep hills without it. It almost chokes.

 

No problem kjetil4455. My dads old 1948 Studebaker had a hill-holder clutch (its was a three speed manual) but they dont make those any more. Sure would be nice on your Spark. Yeah they are a bit low on horsepower for sure..Sharp looking little Chevy car however.

 

So, an update on this case. Turns out the alternator was only charging at 13.5 volts. Fixed the alternator and this problem resolved. It was basically stuttering at low RPM due to low power.