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Hey guys, just been having some trouble starting my car after its been sitting in the sun all day. So it either cranks till the battery dies or i finnaly get it started and i got a sh*t load of black and white smoke come out of the exhaust.

I know its getting flooded with fuel, and i went to my machanic and he reckons its the water temp sensor (tells the computer its extra cold so it dumps fuel in there).
So i'll be changing that first.

My question is - where is the water temp sensor? is it part of the water outlet at the back of the engine? or part of the thermostat? or somewhere else?

Thanks for your help!
Dave

PS most of the time before it doesnt start, i turn the key to the on position without touching the start position and the car cranks over a little like there was fuel in there and a spark but no air.

I think it's the green plug on the back of the engine under the coil pack.

White smoke?

Is the oil residue under the oil filler cap a milky colour indicating a blown head gasket?

You have aftermarket ECU? (Could account for the extra cranks - getting it's sync signal before firing) And, have you done a compression test lately?

Sheck wrote:PS most of the time before it doesnt start, i turn the key to the on position without touching the start position and the car cranks over a little like there was fuel in there and a spark but no air.

Remind us what ECU/Piggy back you are using again? What you mentioned here sounds a little strange?

J

He is using greddy emanage blue.

Yea thats right, cheers boags.

Oil is fine in colour/texture, i'm guessing i got some ring/vale seal leakage from that start up smoke, but i never get any while the car is running properly.

When i was cranking it the other day i took out the plugs and they were absolutely soaked in fuel, had to change the plugs and crank it a bunch more times for it to start.

Cool i'll be looking at it when i get a chance, pull the temp sensor off the sparre motor and see if that helps.

Dave

I have a Flyin' Miata Link ECU in my 1.6l. I can see the H2O temp in my hand controller display. Is this something you can see, as it might point out if your are getting an incorrect reading from the temp sensor?


I can also manually adjust a 'hot start parameter', which I have had to do as the weather gets warmer and I gain more experience with the turbo/ECU.

Oh, and on the point about the engine turning over before you actually turn the key to the 'on' position. Could this be indicating some is wrong with the key barrel setup....could it be worn?

Just my 2 cents worth.

J

Thanks mate, nah the emanage doenst have any water temp display. It basically does nothing (except to compensate for the larger injectors) untill boost kicks in and it adds fuel. Could have something to do with the compensation..

But ye i had no troubles starting it today, but this time i turned the key very slowly and prayed that it would start - that worked. So it could be a combination of temp sensor and ignition problem.

I saw this morning that the stock water temp gauge stayed at a nil reading (ie where it sits when the car is off) for a little while whereas when i started it at lunch time today it was as C or just below it - but more than no power.
Could be the temperature but it could be something else.

Cheers for everyones help!!
I'll post if i get it fixed.

Dave

Yea i'm thinking its an ignition barrel problem cause its started fine the past 3 goes after sitting in the sun for half the day. All i did differently was turning the key very slowly. - weird

Dave

Sheck wrote:Yea i'm thinking its an ignition barrel problem cause its started fine the past 3 goes after sitting in the sun for half the day. All i did differently was turning the key very slowly. - weird

Dave

With my ECU I need to wait around 10 secs after turning the key to the on position, and before starting the car. This is to allow the ECU to boot up and the fuel pump to prime. If I forget and start it quicky, the car will stall after a few secs and then will partially flooded when I try again.

J

Had a mildly modded GTR which you had to prime the pump in the mornings or it wouldn't start. Just had to turn the ignition to the ON position, wait for the whirring of the pump to stop and crank it.

I tend to wait for the fuel pump to stop whirring and then turn the key. An ignition barrel problem sounds likely, Sheck. Fairly common for people with heavy keyrings, too.

Umm cant wait for the fuel pump as as-soon as i turn it to on it semi starts so waiting for the fuel to prime will just put more fuel in an already flooded engine.

Myy keys consist of my car key and my club lock key, al the others are on a seperate chain. But i'm still thinking its an ignition barrel thing.

Had it stuff up once at the end of a long hot day (friday), i turned it off right away and waited a little bit then started it - kept cranking but i noticed that it was kinda running at 300 rpm or so - so i let go of the key and pumped the throttle a bit and it got going. But then on saturday after the full day in the sun it worked normally - i just turned the key a bit slower and prayed that it wouldnt top an already crap day - looks like the car gods were listening

Might take the covers off and see if there is any obviously loose things on the barrel. Quite annoying..

Cheers for the ideas guys!!!!!!!
Dave

Sheck: have you tried the flood clear function on your car??
If you put your foot to the floor then turn the ignition to the run position and hold it there for a bit, then start, it will keep the injectors off for a few seconds allowing any flooding to clear. I have problems at high altitude with my Emanage blue and 330cc injectors as its too rich so i do a flood clear start to get it to fire.