Rich Idle Issue

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Chris28
Posts: 3159
Joined: Sat Jul 14, 2007 11:18 am
Car: 92 s13 KA-T
Location: 757/919
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This one is stumping me, I figured I'd post in here so it gets more traffic. Some background info on the engine, it's a ka-t, 550cc injectors, z32 mafs, EFI Specialist tune. I've been running this particular tune for almost a year and have been running my current turbo setup for about 5 months, never had any problems.

4 weeks ago I had a wastegate line blow off while drifting, ringlands got destroyed. I've since rebuilt the engine and it's back in the car, it's not running right at all though. It runs, but the idle is extremely rough and my AFRs are around 10.5:1. I can unplug any combination of 2 spark plug wires and there's no change in how it runs.

I've replaced the coolant temp sensor, replaced all the injector o-rings, swapped mafs, checked timing, moved around injectors and plug wires, boost leak tested, and it still idles extremely rich. I'm getting code 55 (all good) from the ecu, so there aren't any bad sensors that I know of. Next up is to replace the ignition coil and distributor, but the thing is everything worked fine before I pulled the engine out. I have the engine harness out of the car to check over, but I don't really know what I'm looking for seeing as it was running fine before this happened. Does anyone have any suggestions on what to check next?


User avatar
Chris28
Posts: 3159
Joined: Sat Jul 14, 2007 11:18 am
Car: 92 s13 KA-T
Location: 757/919
Contact:

Post

Fixed it, both cams were off a tooth.


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