? will Lucas fuel cleaner richen up the fuel?

[qwik219d9]

car 99 WS6.

after the FAST intake swap from LS1 intake tech2 tester reads SES light as lean on banks 1 &2 car was not retuned after FAST.

without the Lucas fuel injector cleaner SES light comes on for a 20 or 30 miles then stays off for several hundred miles.

if SES light is on I add the Lucas and a few miles later the SES light go'es off.

? will Lucas or any other fuel cleaner richen up the fuel and cause the SES light from not coming on?

I did a search no results.

Thanks

[farmtruc]

If it does have any effect on the a/f ratio, then it will be very subtle. I've never noticed it.
If the Lucas stuff is making the a/f ratio change (which I don't think it is), then the fuel trims must be on the edge of setting a SES light anyway.
If you just put a FAST intake on your engine, and you're getting lean codes, you'll want to check for a vac leak.
The best way is to use a smoke machine, where there's smoke, there's a leak.