Question-------------------------
Followup To
Question -
I have been the happy owner of my Mustang for the past 4 years. When I first got my car I had transmission problems. My husband and I changed out the tranny with a used one. (That last about a month) We then decided to have AAmcco rebuild my original. Tranny is an EAOD with a high proformance shift kit and torque converter. I then noticed that I was having idleing problems and sometimes my check ingine light would come on. Ok I basically lived with this but in Oct. I was talked into get the three basics done on my car: oil change, air cleaner changed, coolant flushed, and fuel system flushed. I was warned that my car would run funny for the whole tank of gas. The next day the freeze plug rusted out. Fortunately I was at work which is next door to an engine shop. My husband and I decided to have my enginge rebuilt. We also decided to have an E303 cam installed. I had them change my o2 sensors (about the last thing on my list for check engine light) I got the car and it was terrible at first. (Remember the fuel system cleaner?) About 2 tanks of gas later it is running better, and no check engine light but....
Most of the time it seems to idle ok. But once in a while, especially if I am low on gas or have used the lower octane, the car accelerates fine but when I take my foot off the gas my engine chugs. Sounds like it wants more gas. I have increased my idle up to 1000 rpm. Sometimes it idles at that sometimes it is 600-800. BTW I changed my battery out last week. I haven't had the pronounced chugging occure. But still the idle is spuratic. Alot of people have told us that we made a wrong call with the E303 cam but I don't agree. I think the cam is in the car all the time so I should have a constant problem. I would appreciate any insightful wisdom you maybe able to offer. (Even if you agree it is the cam, could you suggest ways that I can modify my car so that it would work.) Thank you sincerly, Toni
Answer -
Toni-
Well...I can tell you right away that the cam is most likely NOT the problem. Thousands and thousands of people have used Ford's E303 cams in everything from stock to big power street motors. The cam could have been installed wrong...but that's pretty rare unless the engine builder has no clue what they're doing (in which case the cam is the least of your worries). What strikes me as odd is that you mentioned an EAOD (by which I assume you mean AODE) transmission. If that is indeed the case, I'm suprised the car's moving at all. An AODE is an AOD that is electronically controlled. The computers that controlled these transmissions weren't in Mustangs until '93. If the car's shifting properly, you most likely have an AOD (unless you're using some kind of external controller like the Baumann TCS system). All of this aside, the most common cures for a bad idle would be to clean out the throttle body and mass air meter as well as checking the idle air control valve. The throttle body and mass air meter can be cleaned with carb cleaner (it's best to do it with the parts off of the car since carb cleaner is flammable) and idle air control valves are relatively cheap. If that doesn't clear it up I would suggest having the fuel injector's checked and possibly serviced. Hope this helps.
Steve
Steve,
Thank you so much for your reply. I am also relieved you too don't believe my problems to be the cam. I have cleaned my throttle body but must admit that it seems to be kinda gunky after a bit. I should take it off and clean it. I have also considered getting a new one. (You know maybe get more power!) OK real quick. Sometimes when I am driving and I begin to brake I feel my car down shifting and then right as I am about to stop the idle slightly increases. -this feels good to me. - car running good. Others when I begin to brake (I can't remember if I feel my car down shifting) but I do know that the idle does not increase and that is when it idles chuggy. (During these times my brakes don't respond as well and I have had some nervous stops) Do you know what causes the engine's idle to change. Could it be my computer?
BTW- I thought I had and AOD tranny, hubby told me different. =) and getting the fuel injectors serviced and or replaced is definetly on my list.
Thank you for being there.
AnswerToni-
The idle problem sounds a bit like a vacuum leak...which would seem strange because intermittent vacuum leaks aren't too common. But vacuum problems could effect the idle and the brakes. It could even cause problems with the transmission. In fact, reading over your last question as well as this one, a vacuum leak could explain a lot of the problems you're having...especially if the engine performs strong at higher rpms (where vacuum would normally be low anyway). It may be wirth having your vacuum lines checked. Hope this helps.
Steve
