DsmEvo87

Dear all,

I have a problem that is bugging me lately did a few searches kinda got some threads kinda like my problem but not exactly, I have an idle/afr's problem when my car gets to operating temp.

Rpm's go a lil up (just like compressor kicks in) wideband goes rich then climbs back to normal feels just like someone blips the throttle, now sometimes it does this in succession 2 to 3 times then goes back to normal. Driving is ok pulling is ok it's just when the car gets to operating temp and idling.

Weirdly enough if I go to a not well ventilated area lile a drive thru car goes crazyy with this problem, managed to film it on my phone:
Things that I tried are : new oxygen sensor, check the iacv (this and throttle body was very clean) checked with a multimeter and the ohms where in tolerance, checked plugs and verified the gap, cleaned maf with maf cleaner but problem is still there.

Have a friend that'll come over in a couple days to swap out coils, maf and temperature sensor as I've heard this could lead to some idle problems and last I would guess injectors?? So now Im here maybe some1 can shoot some inputs my way would be really appreciated.

P.S.: forgot to say car is a evo5 only mods are hks mushroom filter,decat,backbox muffler,dualport bov, turbo timer, boost&wideband gauge & sorry for my typing as english isn't my native language.

turboed350z

iTrader: (1)

sounds like a leak. have you check all the piping, and exhausts?

DsmEvo87

Thanks for your input, hmm never thought about that one and this DID start happening a week after I went to the muffler shop to fit a muffler so will deffinately check this out .

But wouldnt it affect me all the time instead of just when the car gets to a certain temp?

turboed350z

iTrader: (1)

could be the gasket leak in the exhaust piping or bolt not tighten. all metal expands and contracts with heat so i would check the exhaust if it started happing after you got it back from the muffler shop.

DsmEvo87

Just to give update I did find 1 leak fixed it but problem is still there when I run with AC on it will happen less frequently than with AC off

Any other input guys?

roni4g63

iTrader: (1)

you need to do a boost leak test, its most likely a boost/vacuum leak, since it happens at idle, get 2 cans carb or brake cleaner, and spray the **** ouf of the intake manifold, all the hoses, turbo inlet and turbo compressor. if idle goes up or down when u spray at a certain spot, this is your leak.

ps: exhaust leak should not cause that idle problems.

DsmEvo87

Thanks for your input!! Now I read about boost leak tests etc. but unfortunately dont have a compressor at the moment but will bo looking at getting one.

Now for the carb/brake cleaner test just have the car running let some1 monitor idle while I spray it at said locations? That way I know where the leak is coming from? (Just want to make sure I understand)

Thanks in advance!