PPP STI struggles to start
 

Hi all, sorry my 1st post is a teccy one but Im old school and dont do a lot of forums/internet.

I have a 2004 ppp sti, totally standard car and when left overnight or the engine is cold it takes 5-10 seconds of cranking to start and splutters into life. Once started its fine all day, 1st turn of the key, its just the initial cold start. She has always been regularly serviced with decent products or genuine. The odd thing is, I also have a friend with exactly the same problem on a 2003 non PPP sti. They both start, eventually, its just strange.

I'm fairly competant around a car so have done all the initial checks like fuel pump, checked for split vac hoses and cant find anything obvious. Did a compression test on the engine when cold and came back at 130 on all 4 cylinders which I believe is on for a 2.0 sti. Am I right in saying that if it was the crank sensor it wouldnt fire at all?

Check spark plugs
or possible leaky injector.

Mines does it every now and then but has never not started.

It did it on my car before and after I changed plugs injectors and turbo etc.

No leaks from injectors, I did think of that but theyre all dry and sealed. Plugs look clean, not like its flooding or overfuelling. Someone did mention the fuel pressure regulator but even if I turn the key 3 times to prime the system is still struggles initially.

i also changed Fuel pressure reg and still happens.

there was another post about this not long ago must be common ?

I've not had the car long but my friends has done it for about 6 months. I just dont want to go replacing random parts trying to chase the problem. Theres no lights on the dash which makes me think its something mechanical rather than electrical.

ive heard of injectors which dont fully close and leak enough to be the cause
but as i says i replaced mine so can't be them.

if you find anything let me know :)

I've had the same problem on one of my STI's, I've just learned to live with it. Car runs spot on once started, so can't moan that much.

Same as both of ours, runs fine once started and starts fine after the initial sluggish start.

I will keep playing around with it, if I find anything that cures completely it I will let you guys know.

Thanks mate, its reassuring that someone else has the same annoying issue haha

Could a bad earth somewhere be the cause :wonder:

On classics it can be the coolant temperature sensor.

I asked a the same question a week or so ago as exactly the same and the answer that came back is its quite common. I've replaced and cleaned various parts to no avail so think I've just got to learn to live with it.

This has been the subject of a number of threads in the past.
My STi suffered from this for years. I finished up wedging the throttle open after switching off to vent the inlet manifold/head (don't forget to close the throttle before starting next time!) - perfect starting every time after that!
Do a search on the subject on here.

JohnD