I have just rebuilt my engine and reinstalled it, but it is extreemly difficult to get started, and when it does burst into life, I have to keep it above 2k RPM or it will conk out again and refuse to start.

I had this problem before the rebuild but nowhere near as bad as this, as it only used to do it in wet or damp conditions and always once it was warm it would be fine.

My car is a 2.0L WRX with a slight overbore, running an Apexi PFC.

Rebuild/upgrades consisted of:

ACL Race main and rod bearings
Wisco Forged pistons 92.5mm
Eagle forged rods
Cometic MLS head gaskets
ARP conrod bolts
ARP headbolts
Blouche td06-20g turbo


I have tried upping the injectors by 2% under the advice of JollyGreenMonster, but dont think this has made any difference. I have ruled out anything to do with the Lambda as I have tried running it closed loop with no change.

AFR is not excessivly rich or lean when it is running.

I have also changed the turbo to a Blouche TD06-20G, and this seems to be a lot louder than I thought, kind of a loud whining noise (difficult to explain)
almost sounds like a helicopter noise, but faster and higher pitched.

Can anyone please please help, I am pulling my hair out here!

 

You say it is not running excessively lean or rich - are you checking this with wideband or oe sensor?

Is the MAF faulty ?

 

I have a wideband installed. It may be the MAF, but I have no way to prove this short of changing it! Would a dodgy Maf cause these symptoms?

When she does start and I hold it at 2.5k RPM AFR is 14.7 or richer (upto 13's) so deffo not running lean.

Any thoughts?

 

Dodgy maf could cause that,but when it does start and warms up does it get any better?Could be coolant temp sensor

 

checked for any loose hoses? what injectors do you have, i have nismo 740's and she is crap starting since they went in

 

I got 740's too, but these were fine before the rebuild although idle was a little lumpy.

It has also been mentioned to me that the idle control maybe iffy ? dont know how to prove this without changing it for another!

Also, when it does run there is the loud whining noise, which seems to be coming from the turbo area but not 100% on this. It deffinatly doesnt sound normal!