KA24DE idle drops when I hit the brakes/comes to a stop

[s73]

I did a bit of searching on this topic but yet to find an answer to this question.

Here is the story, installed a new headunit today, took it out for a drive. The car idles fine at first (i was warming up the car, didnt drive it for days), but once a while it would bounce 100-200 rpms at idle....but still smooth...i dont see much of an issue here, after all....old car 175k, 92 240sx Se

The car drive fine, but every time i come to a stop (stop light/stop sign) when i pop it out of gear / step on the clutch the rev will drop to around 500rmps and bounce right back to around 900. The funny thing is that it seems like it would stall but it does not! Just dips to 500rpms and corrects itself back to normal.

Just wondering if this is a sign of things to come......Bad EGR? Bad IAC? Vacuum leaks? (i am thinking wild here.....bad ground?)

Please give me some ideas on what to look for, the car was driving fine before, just started to do this tonight.

I am pretty much a noob when comes to 240's, any input would help, thanks in advance.

[monsters13]

the same thing happend to me when i had my talon tsi.. it ended up being a vac leak...the smallest vac leaks can cause the biggest problems...the way i check for vac leaks is turn your car on and spray some carb cleaner around your vac lines and if your motor jumps up in rpms then u have a vac leak..hope this helps...also spray around your intake gaskets

[positron1]

Agreed, I had a vac line with a slit in it once and it caused my car to almost shut off unless I kept giving it gas. Replaced the line and fixed the problem. Also had a problem with coming to stops but cleaned the MAF and throttlebody and fixed the problem.

[Shift_Otaku]

If it isnt a vac line it may also be your idle adjustment. I had a similiar thing happen, except mines whould sometimes stall, and it turned out the idle adjustment screw wasnt set right.

But like stated above its probably a vac line.

[GO240]

i have a vacuum leak around my intake manifold and the car won't rev beyond 3gs its kinda annoying lol

[Razi]

i have a vacuum leak around my intake manifold and the car won't rev beyond 3gs its kinda annoying lol

That sounds more like a MAF sensor problem.