Hey guys I've been having a idleling problem with my evo 7 for over the past few weeks and just wondering if anyone has ever came across this and could help guide me on how to get it fixed

So originally I got a flat battery a few weeks ago and since then I've been having the idleling issue. Things I've done so far are replace the old battery with a new and bigger CCA, got a retune, replaced spark plugs, replaced all vacuum lines along the throttle body, checked and re-tightened all pipes, cleaned the iac sensor and maf sensor and it still is doing the same thing.

It does it on a cold start where it will kick over strong, but then the revs start to die so I have to keep the revs up for a minute or so before it can hold it itself and also when I'm driving with my headlights, foggies and high beams are on.

Im thinking it's an electrical issue since I think I've done everything else that could be done.

so like I said earlier if anyone has come across this before and knows how to fix it it would be truly appreciated!

Thanks guys!

 

Your alternator is going bad.

 

How can it be going bad? I checked it and it was getting still between 13-15v

 

it's intermittent. Mine was "fine" too until I finally caught it messing up. At idle it was good, even under load. I used an amp meter and it also checked out okay.
On the freeway is when I noticed it really dying.
my $10 Harbor Freight tester confirmed lol