Revs dropping - Help? :-)

[Simmo500]

Hey,

I have a 1.0 12v 1998 corsa breeze. When I am slowing down and down-changing from 3rd - 2nd, or 2nd - 1st my revs drop below idle And I get a quick judder until I Put gas on and then It goes ok after this. This happens especially when changing down to turn a corner, or slowing to a standstill. Just wondering if anyone has any ideas what this could be? (it only happens when I brake, and depress my clutch)

Also, sorry to be a pain but when I am accelerating, I get a high pitched whistling noise from the engine bay (Maybe my 1.0 12v is supercharged! LOL!) but it gets progressively louder the harder I accelerate and the faster I go. Could this be an air intAke noise? Maybe I need to change the Air filter??

Any help/advice would be much appreciated!

Thanks in advance!
Mark.

[patersr03]

Hi there Simmo500
this sounds like a common problem, in cars in general especially japanese cars i know i own one.
and it sounds like your MAF Sensor.
taking an incorrect reading.
simple test for you to try, unplug you maf snesor cable drive around blocck, you will notice your engine management light on dont worry about that.
now car drives fine your MAF sensor cable needs a clean try some air duster in connections, if still the same then your MAF itself needs replaced.

If solution does not work let me know.

Thanks

[matty101]

your rev's problem could be your idle air control valve, and your whistling, pop the bonnet rev the engine and have a listen.

[Simmo500]

Hey there. Thanks for your replies! I replaced the MAF recently due to EML and power loss problems! This fixed these issues immediately. I had the AA out about a week ago, (Crankshaft sensor went) but before he knew this he unplugged my MAF and sprayed plenty of cleaning solution into the connections so I'm pretty sure it's not this? Is there a way to clean the IDle control valve or will I need a brand new one? And where is this located? Apologies, my car knowledge is quite limited!

The whistling can only be heard from inside the car, with the doors and windows shut? Really unsure as to what this could be!?

Thanks again in advance!
Mark.

[matty101]

yes you can clean it, check the FAQ

the whistling could be somthing like a broken/worn seal on the windows/sun roof/door? the only way to find out is listen for the noise and work ot where its comming from.