munoz2121

i just drove my car home for the weekend from college. its about a three hour drive all on the highway and then when i got home the car started acting funny. when ever i have to come to a stop the rpm's drop to like 600 and the car starts vibrating heavily, it shakes the whole car and makes a funny rattling noises. When i put the car into nutral the rpm's go up to like 900 and it stops vibrating, im thinking i might just need to change the idle speed faster?, there obviously is a problem though because it didnt do this before i left for home... PLEASE I NEED HELP ANYONE???????THANKS

l_shizzle_l

It should idle a little lower after you've taken it for a long drive, but shouldn't shake.

munoz2121

yea, well its been a full day and it keeps doing it. i would almost say its a gotton a little worse???

munoz2121

and the reason its shaking is because the rpms drop down soo low, but it hasnt stalled yet???

jthorn9

One of the sensors is out. Things to check:

Idel Air Control Valve - long shot, but may be the source
Mass Air Flow Sensor - good culpriate as when they get dirty the car will run like poo poo, easy to check and clean
EGR Valve and or Sensor - when these go out, clog up, or fail, your car will not run right after it heats up
Throttle Air Positioning Sensor - very long shot as this would cause pretty much only a poor idel, but......

munoz2121

the only one i know how to check from the things you listed was the idle air control valve, i took it off this morning and cleaned it with throttle body cleaner and put it back on, adjusted the side of it and its not doing it anymore, but i have to go back up to school today so i guess well see if it does it again, but just incase, where are those other things you mentioned, and how do i clean them/fix them??? thanks so much for the info

jthorn9

Mass air flow sensor is inside your airbox, it's that aluminum looking piece on cold air intakes just behind that first bend in the front, can't miss it. The sensor is a black box that's mounted ontop of the mass air meter, you need a special torx head to get it off.

The EGR valve sits on the passenger side of the engine, see a haynes manual for it's exact location on your car. I know where mine is, on the passenger side behind the upper intake, but I also have a totally different car.

Throttle positioning sensor is that black box thing mounted onto the throttle body.

The MAF and TPS do get dirty over time, which can cause their reading to go heywire, you'll know if they're dirty or not when you get them out because they'll either be clean or dirty, but they're easy to break so be very careful. Use contact cleaning solultion, and a pair of needle nose plires with a little bit of cloth on the tip to clean the MAF, the TPS may be a little different.

i_drive_stangs

mine is doing the same thing and the check engine light is on. my problem is the cam positioning sensor.

munoz2121

thanks for the help guys, ill try check both of those today before i leave, THANKS

l_shizzle_l

http://rpm-mustangs.com/articles/how...alignment.html
That should help you out.