Mr samurai recent started running super rich.  It has what I believe is a fi system off of an early 90s tracker. Ran great a few weeks ago btw could run 80. (GPS 80, not speedo 80)Complete tune up within last 5k miles.  Plus wires air filter seafoam etc. Every thing is clean I have no vacuum leaks. I tried checking my fuel pressure regulator,  there is no gas in vacuum line, I did give it a test run with the vacuum line off just to try and there is zero difference it runs exactly the same if the vacuum hose is on or not. Posting pics of engine bay to help I'd things I need to check. Let me know what to check and how to check it. Thanks.

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No one?

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Since you have an EFI setup, it would be nice if the check engine light was hooked up...which I assume it isn't. It will sometimes help diagnose issues like this.

The one time I had a samurai EFI running rich, it ended up being the fuel pressure regulator. There was no gas in the vacuum line, but I am guessing the diaphragm was stuck. I replaced the FPR and that fixed the running rich issue. BTW, it did not trip the CEL, when I had this issue.

Another thing to check would be the O2 sensor. If it is sending incorrect readings, then that could cause it to run rich.

The fuel injector could be stuck open.

Could be the throttle position sensor is not adjusted correctly, or faulty. This would likely trip the CEL.

Those are my guesses.

Thanks I am letting to figure out how to test all these things. My repair manual is 4 hrs away so that kind of sucks. Uuugghhhh. Thanks for reply.

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Any idea where my map should be plugged in?  Trying to figure out the vacuum mess before I start throwing sensors at it.

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From what I recall, the MAP sensor vacuum line just attaches to a vacuum port/nipple on the passengers side of the throttle body.