Pontiac Repair: 2005 gand stsrand prix 3800 v6, chevron techron, fuel pressure regulator

Question
My car seems to be really hard on fuel. Everyone i take it to can not seem to figure out why. Sometimes it starts  and stalls sometimes sluggish and sometimes works like a charm. weather does not seem to be play a part in this as it dose it whenever it feels like it. it leaves the full mark at 9-11 kms. I get around 200kms per half a tank, sometimes aprox 175 per half a tank. I thought the fuel filter for this car was in the tank (that's what I've been told) but I see you can buy a fuel filter for it. Where is this located and how is it installed. Check engine has never come on. What else could it be.

john

Answer
Hi John:

well it can be a few things going on here. I assume you in canada talking about milage in Kms. I don't know if the Canadian version of this car has a fuel filer or not the US version does not. It' part of the fuel pump module in the tank. As far as the starting it can be a few things. A simple thing is to clean the throttle body and throttle plate with carb cleaner or air intake cleaner. I also believe that there was a calibration for that model year car for a cold start stall or potential of a stall update for the engine computer but again that is here in the states.. You could have a fuel injector(s) leaking fuel it will do 2 things make the car run rich and cause a hard start especially on a hot restart more so then a cold one. You could have a fuel pressure regulator leaking the fuel pressure back into the tank when you turn the key off and that will make a hard restart HOT and a long crank when cold. I would take it to a shop and have them take a look at the engine data and pay particular attention to the fuel trim #'s if the fuel trim is in the (-) % then the engine is running rich causing you fuel consummation issue. You may want to try a product called chevron techron it's an additive for the gas tank that cleans the injector I don't know if you'll find it up there or not. If not stop at ANY GM dealer and get a bottle of fuel system cleaner in in a black bottle with a long slender neck. It is Chevron Techron just in a GM bottle and with the GM $ tag to boot. Good luck :)