Erratic idle speed
 

Would welcome anyones advice,My car is a my200 in basic form except for baily dump valve and ninja back box,.
my prob is this,
She was Running fine until this morning,but i had a impulse to do a ecu resset.i disconected negative bat terminal,then reconected after 90 mins,started up engine did not give her any gas,let her warm up to running temp.switched her off for 1 min then took her for a spin for 20 mins..but then when i let her stand was getting very eratic idling 300-900.
switched her off again repeated the ecu resset again .but prob still persists.
i would be grateful for any advice.
RDB

MAF sensor?

Yes Thanks chris my thoughts to!.

RDB - Almost certain its the MAF.

They are renown for showing up after an ecu reset. (The ecu can learn to live without the MAF).
Good advice is to change it as soon as poss.

Take a look at this thread for more info on failing MY99/MY00 MAF sensors.

Some excellent info on there, especially the 3rd post by "The Judge".

Carl.

RDB -

Took my battery off for a few days charging, then reconnected.
My Idle was "hunting" but after a good run settled perfectly.

If your idle doesn't settle after a run and a bit of town driving then as said already here probably MAF :(

It could also be your dump valve, if its a vta type, they can mess up the ecu a little as they are not designed for our cars (ours use re-circ).

Tony:D

Thanks you Guys for your help with my problem,i shall give it a good steady run ,plus do a bit of town driving to,if that fails to rectify the fault,il take it as soon as possible and get it checked...it seems that the ecu on the my99 &my200 are weaker than on the previous models.after you told me about the previous threads i checked them all.and the hunting symptoms and other symptoms of failed ecu's seem to be identical to mine....once again i thank you all for your speedy and helpful responses to my problem
thanks..Ray Bedwell

RDB - After reading up on the MAF faults and possible engine failure because of them, many people regard the MAF sensor as a service item - So I guess you have nothing to loose by changing it anyway.

I bought one a few weeks ago and it cost just under £80 from the main dealer.
It’s a cinch to fit - just have a look at it and make sure you have the correct Torx bit to undo the screws. Other than that its just an unplug - Replug in.

Just remember that in many cases a faulty MAF does not show up on the ecu error codes – even when you take it to the dealer.

Carl.

Good Advice Carl.i think in future il start to look at the MAF as a service item..£80 is a relatively small price to pay,when the consequences could be imensley expensive....

thanks carl and thank you all...
Ray.........

don't like the ninja back box:cry:

dont buy one then......... :cuckoo:

i buy a new maf m8 as it far cheaper than a new engine. i would not drive it until it had been swapped.



and yes i blew two my99 engines