NA6 irratic idle & loss of power - FIXED

silvermiata · Postby **silvermiata** » Fri Mar 05, 2010 2:38 pm

i had a very similar problem and changed all the sensors just to find out it was actually the fuel pump playing up...

what sasso said about spark testing, undo one of the spark plugs, earth it with a thick cable to the car and put the lead on it, start the car and see if you get spark.try it for all 4... if you do not earth the plugs, you might damage your coilpack...

getting ideas from the forum is always good, but it will just make you more and more confused IMO, take it to mechanic that knows mx5, and get them to have a look at it.. it could be cheaper because you might keep changing various sensors/parts which costs $$.. just my 2c..

Dweezle · Postby **Dweezle** » Fri Mar 05, 2010 3:07 pm

gobsmax wrote:Thanks Mark. I'll give this a go this w/e. How much was your sensor? Still go the old one?

I get the problems regardless of engine temp

Yeah mate..
I have the old sensor still if you want to give it a try??
Just let us know, you can pick it up whenever you want if you wanna give it a go??

93_Clubman · Postby **93_Clubman** » Fri Mar 05, 2010 3:32 pm

gobsmax wrote:I get the problems regardless of engine temp

Alan, the temp sensor for the ecu is a common problem on the NA6, & went on my old one, but it's associated with erratic idling at cold start, so changing it shouldn't make any difference when engine is warmed up & idling erratically.

Have you recently, or at any time disconnected the battery & depressed the brake pedal a few times for 5 or so seconds a time to clear/ reset the ECU?

gobsmax · Postby **gobsmax** » Fri Mar 05, 2010 5:07 pm

silvermiata wrote:getting ideas from the forum is always good, but it will just make you more and more confused IMO, take it to mechanic that knows mx5, and get them to have a look at it.. it could be cheaper because you might keep changing various sensors/parts which costs $$.. just my 2c..

i was thinking of taking it down to mania, but just wanted the satisfaction of fixing it myself, even tho it probably has costed me more in petrol when the car runs rich (12L/100kms) :oops:

Dweezle wrote:Yeah mate..
I have the old sensor still if you want to give it a try??
Just let us know, you can pick it up whenever you want if you wanna give it a go??

Sweet, i'll give you a buzz on sat if im in the area

93_Clubman wrote:Have you recently, or at any time disconnected the battery & depressed the brake pedal a few times for 5 or so seconds a time to clear/ reset the ECU?

The battery has been disconnected in the past, but i never knew to pump the brake pedal. In saying that, when the battery was diconnected, the ecu error did clear but eventually came back :cry:

gobsmax · Postby **gobsmax** » Mon Mar 08, 2010 2:44 pm

FIXED!!!...I think

Removed the coilpack (three 12mm screws), the third screw on the bottom was a PITA to remove but got it out eventually, removed the engine temp sensor (19mm) and polish the tip with wet and dry, cleaned out the contacts and connectors with carby cleaner, reassembled and she been working fine since.

Will fill her up later this w/e and go for a good run and report back.

93_Clubman · Postby **93_Clubman** » Mon Mar 08, 2010 2:54 pm

Good to hear - hope it does the trick!

broady · Postby **broady** » Mon Mar 08, 2010 3:05 pm

gobsmax wrote:FIXED!!!...I think

Removed the coilpack (three 12mm screws), the third screw on the bottom was a PITA to remove but got it out eventually, removed the engine temp sensor (19mm) and polish the tip with wet and dry, cleaned out the contacts and connectors with carby cleaner, reassembled and she been working fine since.

Will fill her up later this w/e and go for a good run and report back.

Yay!