My mech says my ECM is going bad or is it something else?

2000 SATURN
84,000 MILES • 3.0L • V6 • 2WD • AUTOMATIC
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
My car sometimes shifts hard like it slams into gear, there is a delay when I press the throttle and I don't have the acceleration I use to have, It doesn't down shift anymore when I floor it and my cruse control has stopped working. My mech first thought the problem was with the throttle position sensor, so he swapped it out with a new one and it didn't fix the problem so he refunded me the money. Do you guys think it could be something else?
Mar 10, 2014 at 7:49 PM
Advertisement
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
So do you have a 2000 LS2? if so you cant change the throttle position sensor its part of the throttle body assembly.Also do you have any codes in the computer? Most the time the hard shifting on those are caused by a bad line pressure control solenoid.
Mar 10, 2014 at 8:06 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
It's a LW2 and it possibly wasn't the sensor but something to do with the throttle and I don't have the codes but I could probably get them right now, hes like 2 mins away from my house.
Mar 10, 2014 at 8:10 PM
Advertisement
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
The lw2 has the same engine the throttle body assembly has two throttle position sensors built into it.The codes would really help though the exact code numbers not code descriptions?
Mar 10, 2014 at 8:56 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
I drove by and he was closed already, but I'll stop by tomorrow and get em.
Mar 10, 2014 at 9:08 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
Does the reduced performance light ever come on while your driving?
Mar 10, 2014 at 10:06 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
No I've never seen that light on before, just service engine soon is always on but the service light comes on only when it shifts hard which hasn't happened in like a month.
Mar 10, 2014 at 10:17 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
Ok so the code its giving is P1278 and the part that he changed was the Accelerator Pedal Position Sensor.
Mar 11, 2014 at 3:50 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
Sounds like you have a wiring issue.
Mar 11, 2014 at 9:43 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
Well my mech tested all the wires going in and out of the ECM and one of the grounds is not being detected by the ECM or something along t he same lines, he tried an external ground and it didn't work. So should I just replace it?
Mar 11, 2014 at 11:30 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
Thats a expensive guess the only reason I have replaced those ecms is for no starts and you cant link to the ecm with the scan Tool . I have seen guys test the wires and say there good and replace the ecm and end up having bad wires.Bad wires arent as easy as just ohms testing them in some cases yes.But when you have wires that have broken copper strands inside the insulation that work intermently thats where the fun begins.
Mar 12, 2014 at 7:05 AM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
So what do you recommend I do, take it to the dealership for a diagnostics?
Mar 12, 2014 at 2:41 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
How quick does the code come back?If the guy that replaced the pedal just wants to guess whats wrong with your money I would find someone else to work on your car.
Mar 12, 2014 at 7:59 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
As soon as you turn on the car it comes back.
Mar 12, 2014 at 11:59 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
That should be pretty easy to find then all you have to do is follow the trouble tree for the code and it should lead right to problem.
Mar 13, 2014 at 10:13 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
I wish it was that easy for me, I work on computers and like to think I know some things about car repair...I just called another mech and told him the problems I am having and he said most Saturn's have issues with the throttle body and says it will cost me 60 for a diagnostics.
Mar 14, 2014 at 2:06 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
Yes the 3.0 v6 has throttle body and the harness to it issues very common. But they set throttle position sensor codes no pedal position sensor codes.So dont let him replace those for those codes.I know these cars well iam a factory train saturn tech on those cars and worked for saturn for over 16yrs.
Mar 14, 2014 at 6:40 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
I even offered to give him the code but he wasn't interested and just talked about the throttle body issues. He's not available till Monday or Tuesday so I guess ill take it to him.
Mar 14, 2014 at 7:41 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
The throttle body doesnt set throttle pedal position codes the throttle body has the throttle position sensors two of them.This guy doesnt sound that great sounds like a parts changer.
Mar 14, 2014 at 8:10 PM
Avatar
J05H_8O8
  • MEMBER
  • 11 POSTS
So what should I be asking for or what type of mech do I look for?
Mar 14, 2014 at 9:36 PM
Avatar
SATURNTECH9
  • CERTIFIED EXPERT
  • 30,869 POSTS
One that will diagnose the throttle pedal issue not a throttle body issue you dont have.
Mar 15, 2014 at 12:02 PM