Wideband readings

[dwh4784]

I finally got around to joining 2012 with a wideband and ditched the ol' narrowband gauge. Not surprisingly, my readings are not close to what I had been seeing.

I get a great bounce around stoich at idle and cruise, but at WOT it goes to hell. I had my boost set around 14psi and was getting a "safe" light with the old gauge, but the wideband was reading up in the 15-16 range. I've now got my boost all the way backed off as far as I can, 8psi and am seeing readings in the 13's at WOT. This is not good!

I figure either my fuel system is not up to snuff or I am flowing too much air for the factory MP computer to compensate for. The guy I got the SBEC from had the owners manual which is pretty neat, it clearly says that this is intended for a stock T1 engine with no modifications. I have an intercooler, larger turbo, modded exhaust and a boost controller. Could that really overwhelm the MP computer under WOT situations?

I will check the fuel pressure first, but if that checks out I might throw in my set of FFV injectors and see if they bump it up enough. I really thought it would be pretty close but I guess this is why people say to get a wideband in there!

[turbovanman²]

What wideband?

Yep, that will lean out a factory computer for sure, so you need to up the fuel pressure-not a good idea or run larger fuel injectors and turn down the fuel pressure to suit or get a custom cal.

Of course, this is if the fuel system is ok.

[GLHNSLHT2]

He's got an AEM.

[zin]

Those have a warm-up period, so don't take it too seriously for the 1st minute or so, after that it should be pretty accurate, so it would seem like you do have more air than the computer is expecting...

As a quick fix, since you probably don't have the means to do your own cals, is to add an adjustable fuel pressure regulator.

It adds fuel across the board, but the computer can can adjust in closed loop, and will keep the fuel there at WOT, so it should give you the means to make it safe under boost, and if it's annoying out of boost, you can get a cal made from Boost Button to make it "right".

Mike

[dwh4784]

It is an AEM Uego. It's been in there for a week and seems accurate based on the idle/cruise readings.

I do have a Shelgame cal that is set up for the FFV's. The old gauge always said it was dangerously lean, zero lights on a dawes device....I might throw it in there and see how close it really is.