Adjustable MAP sensor

You guys have hear of adjustable MAP sensors , Right?
http://www.go.jeep-xj.info/HowtoMAPsensor.htm
http://www.turbocity.com/product_info.php?products_id=413

http://www.angelfire.com/my/fan/MAP_adjuster.html

Does anyone have experiance with this MOD?

Can it save fuel?

Yes.

I built one, but I never installed it because I don't think I'm running lean yet.

Can it save fuel? Yes. But only if your running rich with bigger fuel injectors.

I save fuel with mine as it was running too rich.

i was discussing the Adjustable MAP priniple with a friend.

Ok ,, so,, if you put in a cooler thermostat , lile 180, 160 degrees ,, the fuel mixture will remain too "rich" ( higher fuel to air ratio) because the ECU will think the engine is still cool.:shiver:. therefore the plugs will foul faster and the fuel economy suffers..

However,,, if you adjust the MAP to run "lean" (higher air to fuel ratio) , then you can run the cooler thermostats with out fouling the plugs and keeping the fuel economy from suffering.

Well, thats the theroy , anyway:idea:

Does that sound right, or reasonable to you??

how would I know if my car was running lean or rich ?
all I know is that i have very little carbon in my muffler tip , I think this is a good sign ?

I have been running one in my 90 for a couple of years (5). It has been a god send for passing DEQ. I replaced my stock injectors after 150K and was running about 5.45V to pass DEQ with my Borla exhaust system, head to tail. When I put new injectors in, I had to adjust to 4.34V and use hotter plugs, Splitfires, to pass. My Jeep never ran this good new!

karim_gabra said:

how would I know if my car was running lean or rich ?
all I know is that i have very little carbon in my muffler tip , I think this is a good sign ?

Click to expand...

i would guess that a clean tail pipe is a good thing too

Possibly also, by looking at the condition of the spark plugs.

There is a chart with pictures in all "Hayes" manuals that show spark plug conditions and what they mean.

Very hard to tell via the exhaust now a days with lead free petrol. Was so much easier just looking for the right shade of grey before.
I use a wideband o2 sensor and digital display that I borrow from a mates workshop.