Hey guys,

I was rocking the stock injectors @ 205k. 2005 MCS.

I decided to put a new fuel filter in, the black vacuum canister thing for the fuel vacuum line, and some new 380cc JCW injectors. The car seemed like it was doing fine, but then I started to get P0303 and once or twice, “Random missfires.” Also P2096, but then I went back in and saw my injector o-rings tore so I replaced them.

I got a P0172 yesterday, but I mainly just get P0303 now.

I’m wondering if I have a leaky injector, or maybe a fuel filter o-ring didn’t seat right.

I replaced my lower 02 sensor, fixed a minor exhaust leak, thinking this would fix my issues but no dice.

I am running a 90 bend spacer for the O2 because it was rubbing on the heat shield.

Im just looking for ideas here.

I did have Adrian tune the car after I put the injectors in but I got the rich codes before he tuned it. I thought I had them fixed but apparently not.

Only mods are 380cc, Detroit BPV, 2% overdrive, 15% boost, Alta intake.

My plugs have about 25k along with the coil and wires.

Any ideas?

 

Your engine tune must match the injector size or you will get fuel trim errors. Fix the tune or put stock injectors back in.

 

The car was tuned for the 380cc.

I did put the Injectors in and it threw the rich codes before the tune. Then the car got tuned, I fixed the exhaust leak, replaced the O2 sensor.

I’m wondering what to check. I’ve been through all the vacuum lines they are good. I might get a smoke tester but I’m thinking to replace my ignition parts and maybe compression test.

 

Just to confirm, you have the 90° spacer on the post-cat O2, right?

 

Yes. The one in the tunnel. It was rubbing on the side so I kinda have no options

I still have the stock cat and header. Stock exhaust until the muffler essentially.

 

I’m somehow running rich and lean. The car is driving ok, just not idling well. It never dies or anything just revs a bit.

 

At least this one gent had an issue with using a spacer. I replaced the exhaust gaskets and fixed the only leak I had so I’m thinking it a possibility.

 

I had a 2096 pop on mine, but i busted a weld on the flex pipe of the ebay header. Replaced it with Milltek non catted header, replaced both O2 sensors, reset all adaptations and havent seen it since. For my bottom O2 i have a spark plug anti fowler drilled out and O2 sensors in it, no codes before Adrian tune, and i didn't have him tune it out since everything was working. I do have one of those 90 degree bungs with catalyst, sitting at home collecting dust.

 

I used an open one. It’s just a spacer no narrow holes or anything inside.

I’m going to try and replace the other O2 sensor with the post cat one and get a shorter one, hopefully it will fit. I’m just trying to rule stuff out. I got new plugs and stuff on the way also. Will report back.