steven975

Hi, former member, plan to re-join...haven't posted in a while.

Anyway, sometimes when going back to idle, the engine will drop a little below idle (600-800RPM), and shudder. It does not always do this, but it's enough to concern me (don't want the bearings to go).

I have a 2002 with 72K miles. MAP sensor is original. I definitely need a valve adjustment, and maybe new plugs.

I've tried an ECU reset, but it comes back. Should I get the adjustment done, and plugs, or should I just go ahead and get a MAP sensor?

suzuka-blue-s2k

It's normal.

zeroptzero

clean the idle control valve and the small orifice under the map sensor, using throttle body cleaner for both. You can try a map whack too, or clean it with some electronic parts cleaner.

s2cho

bet your filter is really filthy
i had this problem a LOT
and i installed my aem v2 intake 2 days ago and it took it all away and my shifter doesnt vibrate anymore,
seems like if the oem filter to the stock air box gets dirty it constricts a lot of air flow
and the car has to really try to get air into the engine.

so try a new oem filter or wash/spray/re-oil the one you have now

steven975

Did the filter about a month back...it WAS filthy.

The problem has decreased now that I think about it. It also seems to happen when I get a quart low on oil (down about to the L mark). I don't think starvation is occurring at a quart low (hope not, LOL).

I'm going to do a valve adjustment as I KNOW they are loose...they're very noisy. Also will try the MAP cleaning.

zeroptzero

If doing the MAP whack or cleaning do the Idle air control valve cleaning at the same time if you can.

steven975

Thanks, that's not a regular thing, though. I almost always have a spare quart in the trunk and check whenever I put gas in the car. Still, we all slip up sometimes...

jakestr

clean the IAC and Map. Makes a difference. In the end, its pretty normal dont be too concerned

SGTForti

This is some good info. Will clean mine too. Also what other synthetic oil burns slower than mobil 1? Thanks

amac2K

had similar problem that become worse and car was actually stalling at times. i replaced map, spark plugs were good. what fixed it was cleaning the throttle body.