i just joined today i bought a 2000 cadillac sts 2 weeks ago i bought it with some problems in it checkengine light is on and some times it shakes and bad bad bad gas mileage the computer reads 15 mph avg the onwer said it needs coils i fixed the front coils my self but still i have a promblem and it still shakes i need help.

1-can i replace the back coils with front coils does it matter ?

2-how can i fix the gas mileage and if anyone knows how to fix any prolems i just mentioned?

 

Your description of shaking seems consistent with ignition coil problems or another misfire. If you get the computer scanned it will tell you whatthe Check engine light is about. You can get into control centre by following directions at the link below:

http://myweb.accessus.net/~090/cadidiag.html#2000

You need a different part for the rear bank ignition coil.

City gas consumption will improve once shaking is cleared up but it is winter and mileage is generally poorer. I think you might get 16 or 17 mpg in City but not much more. It is a 300 HP V8.

 

thank you so much for your help i fixed coil myself its the same part for the front and the back bank no more shacking and gas milege is alot better but i still have check suspension system and change braek pads but i installed new braeks what could be the problem i hear a strang sound when i push my braeks do you think i still need replace them and suspension it says code C a friend of mine said it could be the sensor where is it located in the car and i can get it fix by myself money is tight now i can afford to take it to a shop if i can see a picture that will be awsome so i can know where it is and what is it called