Hey guys, new user and new Focus owner here. I picked up a 2000 SE with the 2.0L SPI SOHC engine about 3 weeks ago. Everything went fine on the test drive, and then, within a couple of days of getting it home, I started having a problem with the engine surging. When I start the car, and whenever the car is in neutral (including between shifts, at stoplights, etc) the engine will race for maybe 5-6 seconds, then slowly fall back down to a normal idle. I can tell it's doing it when I'm in gear sometimes as well. Also, if I'm in neutral and blip the throttle, the revs hang for 5-6 seconds, just like when i star the car.
I pulled codes, and got P1506 Idle Air Control Over Speed Error, and P0171 System too lean, Bank 1. I know the idle control valves can sometimes be a problem on these cars, so I went ahead and replaced it, which did not solve the problem. I also cleaned the throttle body and MAF sensor. I unplugged the TPS to see if that might be bad, and it was much worse, so I'm guessing that's ok. I've checked as best I can, both with my ears and eyes, and starting fluid for a vacuum leak, but didn't find anything. The only other thing I can think to add is, when the engine surges, the throttle plate is not opening. Well, I say that, but I can't visually verify, since the car won't run if the MAF isn't getting a good reading, so I can't disconnect the intake to actually watch the throttle plate, but I can tell you the throttle linkage on the outside of the throttle body where the throttle cable and cruise control cable attach doesn't move when it surges.
Can anyone out there help a noob out? Not only is it annoying, but rather embarrassing at stoplights and in parking lots.
I pulled codes, and got P1506 Idle Air Control Over Speed Error, and P0171 System too lean, Bank 1. I know the idle control valves can sometimes be a problem on these cars, so I went ahead and replaced it, which did not solve the problem. I also cleaned the throttle body and MAF sensor. I unplugged the TPS to see if that might be bad, and it was much worse, so I'm guessing that's ok. I've checked as best I can, both with my ears and eyes, and starting fluid for a vacuum leak, but didn't find anything. The only other thing I can think to add is, when the engine surges, the throttle plate is not opening. Well, I say that, but I can't visually verify, since the car won't run if the MAF isn't getting a good reading, so I can't disconnect the intake to actually watch the throttle plate, but I can tell you the throttle linkage on the outside of the throttle body where the throttle cable and cruise control cable attach doesn't move when it surges.
Can anyone out there help a noob out? Not only is it annoying, but rather embarrassing at stoplights and in parking lots.