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SRSmith · 09-25-2019, 05:27 PM

I spent a couple hours on it this evening. I'll try to make this as concise as possible.

I installed a Fuel pressure gauge. When idling (900 rpm), the pressure remained at 38 PSI (46 with FPR disconnected). Upon shutting off the engine, it immediately dropped to 32. Over the next 5 minutes, the pressure dropped by 10 PSI.

AFR started at 14 but moved up to 17 when the engine warmed up. The reading jumped around a lot, so the most precise number I could get was a whole number.

I took it for a drive. First acceleration was ok, but the rest of the time it lagged when I hit boost. When giving it throttle AFR went up to and Fuel PSI went up to 50.
https://drive.google.com/open?id=147...qUad81MeN7A9vD

When I got back , I got the CAS code from the ECU. I retimed it and the code went away.

At idle: AFR 15-16 PSI 38
I took it for another drive. It was a little better.
https://drive.google.com/open?id=13h...M1UG9liFK8jK0w

I got home and pulled the plugs. As expected, they're dry.
https://drive.google.com/open?id=13g...csVMwHYPM6GpSo

I replaced the iridium BKR6's with some new BCPR7's.
I took it for another drive. It ran even better. Now and then it was able to build full boost, especially after letting off the throttle for a while.

When it's working: AFR 12-13
https://drive.google.com/open?id=13R...rujT2t6pnKmopY

When it's not: Throttle is to the floor.
https://drive.google.com/open?id=13B...Z0O9gHoJQMw9Tc

Pulled off the fuel pressure gauge. It looks pretty restrictive (Harbor Freight).
https://drive.google.com/open?id=13B...M1wveXrt6Mm1MH
I ran it again and it seemed about the same.

I'm thinking I have a fuel problem. Or maybe a boost leak? Should I start with a smoke test? I still have the boost controller bypassed, so I should be at stock boost.

What do you guys think? I don't really want to drive the car any more when its lean.

And thanks so much for the input.

PS: Anyone want a Greddy Exhaust? I'd like something a bit quieter.

Edit. Had some of the videos mismatched. Fixed that.

09-25-2019, 05:27 PM	#9
SRSmith Leaky Injector Join Date: Jun 2019 Location: Wisconsin Posts: 91 Trader Rating: (0)	I spent a couple hours on it this evening. I'll try to make this as concise as possible. I installed a Fuel pressure gauge. When idling (900 rpm), the pressure remained at 38 PSI (46 with FPR disconnected). Upon shutting off the engine, it immediately dropped to 32. Over the next 5 minutes, the pressure dropped by 10 PSI. AFR started at 14 but moved up to 17 when the engine warmed up. The reading jumped around a lot, so the most precise number I could get was a whole number. I took it for a drive. First acceleration was ok, but the rest of the time it lagged when I hit boost. When giving it throttle AFR went up to and Fuel PSI went up to 50. https://drive.google.com/open?id=147...qUad81MeN7A9vD When I got back , I got the CAS code from the ECU. I retimed it and the code went away. At idle: AFR 15-16 PSI 38 I took it for another drive. It was a little better. https://drive.google.com/open?id=13h...M1UG9liFK8jK0w I got home and pulled the plugs. As expected, they're dry. https://drive.google.com/open?id=13g...csVMwHYPM6GpSo I replaced the iridium BKR6's with some new BCPR7's. I took it for another drive. It ran even better. Now and then it was able to build full boost, especially after letting off the throttle for a while. When it's working: AFR 12-13 https://drive.google.com/open?id=13R...rujT2t6pnKmopY When it's not: Throttle is to the floor. https://drive.google.com/open?id=13B...Z0O9gHoJQMw9Tc Pulled off the fuel pressure gauge. It looks pretty restrictive (Harbor Freight). https://drive.google.com/open?id=13B...M1wveXrt6Mm1MH I ran it again and it seemed about the same. I'm thinking I have a fuel problem. Or maybe a boost leak? Should I start with a smoke test? I still have the boost controller bypassed, so I should be at stock boost. What do you guys think? I don't really want to drive the car any more when its lean. And thanks so much for the input. PS: Anyone want a Greddy Exhaust? I'd like something a bit quieter. Edit. Had some of the videos mismatched. Fixed that. Last edited by SRSmith; 09-25-2019 at 07:46 PM..