04 sti uk poor start warm and cold
 

Hi, thanks for looking.

Jumped in and bought myself a my 54 uk sti, over the moon with it to be honest. Have had it for around 2 month now but have discovered a problem i dont want to live with.

If the car has been left over night the first start of the day usually takes 5 to 6 cranks of the engine before it comes to life. (Always let the fuel pump finish priming) there is a very rich smell of fuel.

Once running runs fine.

If im at work i leave the car for 8 hours. Occasionally when trying to start after this time it can take a while to get going, engine will tick over but at very low rpm (low enough it dosnt read on the rev counter) for about 10 to 20 seconds then picks its self up to 1500 rpm, it almost sounds like it isnt firing on all cylinders.

If i leave the car for a few days then the first start of the day is considerably worse, up to 10 crancks of the engine and starts on really low revs but will eventually pick its self up.

This cant be (normal) can it?

Car is only run on v power and ive just had the spark plugs changed as i thought thwy could have been a cause.

Many thanks in advance.

is the car standard?

Yes all apart from a dump valve and hella horns

Just to add, the fault dosnt happen all the time, yesterday it started straight up after being parked at work all day, and again this morning i had no problems.

My MY04 UK STi takes a few turns to fire up. The engine has been rebuilt and it still does it even after that. I think there are a few people on here who have a similar problem, but once the car is running it's spot on.


I've checked sparks, vacuum leaks, earthing, fuel pressure, injectors, air sensors even the octane of the fuel in the car... just doesn't want to start up quickly!


My MY04 JDM STI fires up every time first turn on the key...


This might help;


https://www.scoobynet.com/general-te...injectors.html


Not sure how applicable if you're on standard injectors though.

What dump valve have you got on there?
You're not touching the loud pedal when cranking are you?

Thanks for that

I ever put the dump valve on, came with it but looks like a lump of aluminium, no make on it.

And no never touch accelerator when starting.

I will try to get a video recorded to show problem cheers

Take a pic of the dv too,sounds like an eBay special? Not good for the car if it is.

Common issue with STI's. Mine can be the same (although no where near as much as yours).

Been a few threads on the Essex forum, and basically there doesn't appear to be a one size fits all solution, and changing injectors hasn't been proven to work consistently.

Mine is lightly modified, and I get much better results if I switch the ignition on and wait for the fuel pump to prime, and re-do this process again (maybe even twice) before starting. Then it starts miles better.

https://www.scoobynet.com/scoobynet-...rt-issues.html

+1 bro but why does the op smell fuel is the question I'm thinking about:confused: are all fuel pipes checked for cracks while started under bonnet? Has the rear bench been removed and connections on the fuel pump lines been checked ?
Just my 20p's worth:thumb:

Yeah get that pile of crap off the car and put OEM back on.

Might also be worth double checking it is on original cat and back box.

Mine is on a half decat and Vortex Afterburner, and always smells of fuel upon start up. Smell should go very quickly.

Mines on full decat blitz nur spec and no smell of fuel at any given time only time I smelt fuel was when my fuel pipe going to the filter was ever so slightly cracked couldn't tell tell it was leaking there when on idle

It has the prodrive exhaust system but will take some pics later on today

I will make this my weekend job!! Have not checked fuel lines.

Joys of Subarus huh :s No consistent answers to these things.

True indeed my freind we can only assist with our past experiences and knowledge and hope the op resolves the issue without any more problems it's what makes us enthusiasts appreciate each other IMO and that's priceless:thumb:

https://cimg4.ibsrv.net/gimg/www.sco...45e04c5e01.jpg

The dump valve in question

https://cimg5.ibsrv.net/gimg/www.sco...1d399783c7.jpg

No make on it that i can see

Can't beat the standard recirc for me. Cheap enough off breakers on here as well

That is am eBay special bro as suggested previously I'd get it ripped right off its probably leaking its t!ts off can't see the idle or running of the engine being smooth neither this is not a chav rant that is a sh!t dump valve from China :cry:

+1 :thumb:
Needs to be installed into the nearest wheelie bin!

No problem, any one have the part no for the standard recerc valve?? Or any one got one for sale? Cant post in the wanted section yet..

Try Matty at MB Developments,he advertises in the breakers section.

A mate of mines had that very same dump vale on his and it blew the end cap right off stripping the 4 bolts. Bin that right away and switch it out for original or buy a more reputable valve like a Forge unit or HKS.

Update for any one interested, fuel lines checked over the weekend, all good. Fuel pump checked all good. Managed to get a hold of a standard re circ valve. Fitted on saturday, no problems so far, however i am letting tje fuel pump prime twice before starting.

What i have noticed which i think is down to the dump valve is that the car idles way better now, it settles at operating idle alot quicker too.

Cheers

Happy days!
The car will appreciate you losing that dump valve :thumb:

You shouldn't need to prime it twice if the problem persists go for an upgrade on your fuel pump :thumb:

The drive on it must be more smoother throttle wise etc without that thing on it

Same issue on my stock sti ppp blob