Power issues with mx5 mk2 in wet or cold conditions

[Milarepa]

When it is wet/damp I have been having problems when I start the car up. It was occasional but its become such a regular occurrence its now gone to a garage that specializes in mx5's.

The symptoms:

Starts first time but struggles slightly to start, like it coughs once. Until the car warms up, it loses power when I lift off the gas. Electrics go dull like its going to die. Once its warm its fine.

The problem got worse with the bad weather last week. The car seriously struggled like it was running on two cylinders. Major lose of power at junctions almost stalled 2/3 times, but once warmed up it was fine.

I've changed ht leads to mose colbolt 8mm. Switched cam sensor for a spare one I had. Garage have fault tested it but no faults arise. Ecu dry...

I've read millions of forum posts but no one seems to have a answer but it looks like a common fault.

Its fine when its warm, starts first time and drives really well. Its only an issue when its wet/damp

Any help or advice would be gratefully appreciated

[Robb F]

Squirt some WD40 in all the electrical plugs.

[Milarepa]

I've left it with them till sat with the hopes they will be able to replicate the issue depending on the weather. If they cant then I'll get them to wd40 everything.. hope it resolves it?


Is this common in the mk2.

Edited by Milarepa on Wednesday 23 September 17:53

[BIG DUNC]

Battery or alternator old?

They would be the first things I would change if the garage don't come up with anything

Ask them to check for fault codes (even if the engine light isn't on)

Edited by BIG DUNC on Saturday 26th September 15:52

[MX-5 Lazza]

Check the battery connections are secure. Remove, clean up the posts & rings and refit.

[tr7v8]

The wife's one had this a while ago, only when cold. After a lot of investigation it was the coil pack.

[Milarepa]

Got it back from garage last Saturday. Typically it was warm and didn't help which left them scratching there heads.

It did play up for them a little bit on one day so they fault tested it and it came up with an unusual code, they changed the mass air flow sensor and another one which improved the start up cough but its still there just not as bad, but then it hasn't rained or been really cold so cant say if what they have done has helped. I did get them to wd40 all the connection

It is still dropping its revs for the first 5-10 minutes of driving when pulling up to junctions but as soon as it warms up its fine

I will do a battery check and see what the connections are like. I did Consider the alternator path but they said it was unlikely.

Its really frustrating as I love my mx5 more then the wife sometimes but this is beginning to nag me just as much lol

Edited by Milarepa on Thursday 1st October 08:13

[Milarepa]

So on the way to work it seems to struggling in 2nd and 3rd, like its kangarooing, even when the car warmed up. No loss of electric's just struggling, revs kept dipping when doing it. Only at junctions.