Subaru poor starting.
 

Hello. I'm quite new to these forums. I've got an 02 bugeye wrx EJ205.

Basically, Every now and again. It struggles to start. Literally first crank of the key. It starts, but it's on the edge of stalling. But once it picks up, it runs fine, drives 100%. Secondly, sometimes when the engine is warm, and you try and start it. It misfires for about 10 seconds, then it clears and it's fine. But it doesn't always happen. I've given it a compression test and all the cylinders are all even. 15 bar I think that it was. If anyone could help I'd be very grateful.

Many thanks.

change your plugs to 7's and not 6's and clean your maf
you will need to gap to your boost setting

Use a code reader via eBay they are around 15 £ , car may not show a cel , it could be many things causing it , where are you based

I was in a rush to reply and see where you are now , definitely try a code reader , give the maf a clean if that improves it after cleaning maf then great , the maf will not normally show a cel so is it time to replace or swap with some one else's as they are not cheap , plus check fuel pump pressure

Not an uncommon fault. There have been a number of threads on these or similar, symptoms.
Do a search through the archives.

JohnD

Thank you for the reply. I'll have a look into the plugs. What do you mean by changing them to 7's? I've replaced them with the iradium ngk ones. They're gapped to the standard settings. The vehicle itself is standard apart from a backbox. I've scanned the vehicle and there's no codes present. I've cleaned the maf before, but it hasn't made any difference. Is there a way to check that the maf is at fault? I'm based in West Sussex.

Many thanks

No way to check a MAF, only substitute a known working one.

Some will tell you to unplug when the engine is running, don't bother, it's nonsense.

Photo your maf and post it with the part number and see if it's the same as any one local to you , fuel pressure is easy enough the guages can be bought on eBay for 12£ to your door , was it showing any 02 faults , on code readers there are extra monitoring menus did you find any thing there , do you have an air leak in intake system or any where else ?

I didn't think that there was a waybtp check the maf. I'll take a photo tomorrow and post it with the part number. I haven't checked for the right fuel pressure. What sort of pressure should there be? There are no codes present. I've looked at live data and there isn't anything that would indicate that there's a fault. What I'll do is I'll take a picture of live data and post it on here? There isn't an air leak which I'm aware of. I've sprayed brake cleaner all round the joins of the manifold etc. And it didn't pick anything up. The only other thing is I'm not 100% is that there's a cheap unipart battery on it. 450cc 60ah. To me that seems low. On my old scooby I had a bosch s4 on it. But I don't think that it would of made a great deal of difference or not?

Many thanks.

I bought a new maf and 02 sensor maf was 70£ , 02 from Subaru as they last , and was some where between 200 and 300 £ , the issue has mostly sorted itself , poor earth ? My 02 and maf were not showing faults , battery if voltage is bad is a possible , what's the battery before cranking during and when it's running , I would expect 12 v before , no lower than 9 v when you crank and 14 plus v when running , fuel pressure around 43 psi higher when fuel regulator air supply disconnected , other option do a reset , take battery lead off and pump brakes about 30 times and reconnect