Idle bogs down coming to a stop

[dareo]

When im driving and i have a stop ahead, often my rpms go down to 500 or less, a few occasions the motors died. It seems to happen more if im in neutral, and happens worse if i've just been driving hard. For example, i took a mountain twisty drive thats about 15 miles up and down, extremely fun road, drifted a few corners, but when i got back down and stopped the motor died. I do have a check engine light on, but i cant afford to get it diagnosed just yet, one shop wants $45 for a diagnosis and Autozone says they cant check an 89 nissan. Other than the idle issue only when im stopping, its a good running KA. It does burn a little oil when driven hard, but thats it. Is there any way, (besides unhooking the battery for 24+hours) to clear the check engine light?

Thanks!

[quiksilvia]

do an ecu diagnostic, go to http://www.240sx.org and under the faq the directions are there. check all of your vacuum lines, sounds like that could be the problem

[bmxruler4130]

you may have a vacuum leak. check all along the intake for any holes or disconnected hoses. my car did the same thing, because there was a hole in the intake.

[sammy]

be sure to check the AIV valve also........mine did that......I removed the AIV, and end of problem.....you will prob wanna clean it if it is gunked up

[dareo]

Thanks for the pointers guys, i did some more reading into the many causes of Idle irregularity on our cars and my vacuum stuff and the idle valves definitly need a look. I still need to aquire a service manual, and a job for that matter.

[lbrowne]

Wheres this AIV valve? I should check that on mine since I have the exact same problem on my 89 coupe.

thnx

lbrowne

EDIT: excuse me while I smack my head off my desk, I didn't even see the AIV sticky in this forum :thinker

[soilwork240sx]

i had the same problem on my 93 hatch. ended up being an egr gasket on the intake manifold

[leper421]

new fuel filter and a throttle body cleaning fixed it for me.

[xyster]

I'm having the same problem on my 92 hatch. I've checked and rechecked all the vacuum lines, removed the AIV and removed/plugged the associated hoses. I've also regrounded the engine and checked/cleaned all the grounds. The engine is fully tuned up too (all new: plugs, wires, air filter, fuel pump, fuel filter, etc etc). I think I'll just ignore it since my CA should be installed in about a month.

[dareo]

I fixed my car, as near as i can tell, by removing the vacuum hose that connects to the airbox and plugging the airbox hole. This hose just kinda sucks air into the exaust as needed right? So its not going to cause any problems if i leave it unhooked? Because my car runs much nicer now ildewise. So far i havent been able to get it to spike down at all.