RPM Drop!!

[01svtcobraxx5]

Ok so i need some help. I own a 2001 Cobra with some upgrades. However about a couple months ago for some reason my Rpm will just drop all the way down to 0 and die. Just recently it started to get worse. Whenever i'm driving and I take it out of gear the RPM doesn't come down slow, and just falls all the way down until the engine dies on me, and it seems to wanna do it at the worst times like when im on the freeway or going down a hill. I think it might be my altenator but not sure. Appreciate any help thanks.

 

[COBRA90GT]

Who told you the alternator was bad? Have you had the battery tested? How did that person come to that solution?



It sounds like a faulty IAC would be a more likely culprit or perhaps a vacuum leak(s), IMHO.


Also, what mods do you have ?

Performed any recent work under the hood, especially along the air intake tract (air filter, upper intake piping, etc)? Perhaps a recent mod or work under the hood has caused this drivability issue...

 

[bditty50]

I bought my 01 cobra in Dec and had the same issues after doing my diablo predator tune to fix my gear change. So its when you come to a stop after the car is warm I'm sure it drops and you have to rev it or let it fall on its face. Well I was getting pissed with this and it made me not want to drive it. So long story short I replaced the IAC and it helped catch the drops alittle bit but, not fixed. So I updated the software on my predator and it is completely fixed. From what I've heard if you have a cold air intake the rush of air in the intake causes this and the IAC is stressed with the job of keeping idle. I also cleaned the Mass air sensor and that helped. So I would just recommend a tune and that should fix it.