[philbo9]

I recently installed a new head unit into my 04 mach 1 about a month ago. Ever since then my car has been acting strange. It will idle at around 1300 rpms and drop way down to 200 rpms and sometimes just turn all the way off, also while i am accelerating the car is hesitant and feels as if the whole engines timing is off. I dont know if it is coincidence that these problems started right after i put the new radio in or not, all I know is it was running like a dream before and now its not. I was just wondering what some of the causes could be for this problem or if it is indeed related to the head unit instillation.

 

[Rosco]

Did you install the head unit or did a shop? Check lines in the engine. If you got it installed they might have disconnected a vacuum line.

 

[BigB227]

Check alternator, battery, COPs and spark plugs and move on from there

 

[1996mustang]

Does it have engine codes? If so i would start there go to autozpne and get ur codes read free then post them up so we can help. Ps.....autozone isnt ase certified so i wouldnt really listen to them they may sell u something that wont fix the problem and may make it worse. I.e that coolant stop leak crap.....doeant work amd creates more problems like clogged water passages.

 

[philbo9]

@Rosco- I installed the head unit myself and all the vacuum lines are still intact.
@BigB227- I will check them today, thanks!
@1996Mustang- There is no check engine light at this point so I don't think there would be any codes.

 

[jjsg09]

Idle air control valve? Throttle position sensor? Check those

 

[philbo9]

I Put in a new throttle position sensor today and reset the battery. The idle is already running back to normal. I am going to put in new plugs as soon as I get the chance because the engine is still hesitating. What kind of plugs do y'all recommend?

 

[jjsg09]

I Put in a new throttle position sensor today and reset the battery. The idle is already running back to normal. I am going to put in new plugs as soon as I get the chance because the engine is still hesitating. What kind of plugs do y'all recommend?

Always factory Motorcraft and don't change them when the engine is hot or even warm wait for it to be cool. You can possible damage threads in the spark plug holes if you don't wait.

 

[philbo9]

ok will do, thanks!

 

[FordFan]

Check your oxygen sensors and your mass airflow sensor also, they control how the idle and acceleration respond.