borat52

Just changed my 380cc injectors for 440cc injectors, both phase 1 fuel rail types, on my 1993 WRX. 1 has sealed nicely but the other 3 are spewing out fuel when I pressurise the fuel system.
I did not change the O-rings, will this be the problem?
thanks
will

jim litten

I'm assuming that the o-rings were already on the injectors, or did you swap them off the 380s.

borat52

Already on the injectors, thought I'd be a arrogant sod and just pop them in without new O-rings despite what the consensus on this forum said. Would the O-rings alone be the cause of this?
cheers
will

jim litten

Did you make sure all the old ones came out with the old injectors, if any of the old ones were left in the rails then the injectors wouldn't seat all the way down and would leak, failing that you may have nicked them as you installed them, it doesn't take much to damage an o-ring, BTW you did re-install the little rubber bits that sit on top of the injector and under the cap.

borat52

All O-rings were checked as they came out as present and accounted for, and the little rubber bits also went back in too. Pretty sure I did everything right with the actual bits that went back in, just a bit miffed that one sealed and the other 3 did'nt(Of course being the first time that I have done this I put everything back together in the engine bay before actually pressurising the system). Going to have another look tonight/tommorrow now I have new Orings and some grease for them, will post back either with jubilation or complete frustration. Still got the FMIC to fit too which I rekon is going to be a complete and utter pig of a job.
thanks for advice

Area 52 Autosport

Injector seals are quite fragile, new seals each time you put them in and a nice even coat of light grease, twist them in carefully, you can see them start to roll if one catches.

borat52

Yes should have listened to that advice from word go. New o-rings all round and a small amount of grease and they went in a treat.

Now for the FMIC and remapped ESL chip and hopefully it will all be worth it.

To anyone who is thinking about a new set of injectors its a really easy job. I'm not very good under the bonnet but with what I read on here and by taking my time over the job it made it very staightforward. Took 3 hours initially to get the old ones out and new ones in then an hour and a half the second time (with new O-rings). Please dont skimp on the replacement O-rings as you will end up having to redo the whole job as I did!

Will do a proper write up on my state of tune when its all done as I have really enjoyed this car, a year ago it was a standard 1993 WRX wagon with just a cat back exhaust. Have since fitted TD05 turbo, Apexi induction, HKS DV, ESL chip, decat downpipe, and now bigger injectors, dawes device, knocklink, afr gauge and awaiting the FMIC. After all of that I have an ESL chip to take account of the injectors and FMIC and it should be good for around1.2bar boost and 300+bhp. All of this has been done for about £1300, which is pretty reasonable to take the car from about 220 to 300+BHP. Just crossing my fingers that its reliable up there!