I am having a crazy map sensor problem.
I can boost to my normal 7 pounds in first gear.
In second if I boost to or past 5 to 6 pounds I get CEL code #3
In third if I boost past 4 pounds same thing
fourth I get to 2 pounds same thing
fifth if it even thinks it see's boost I get CEL

The set up is a LS/Vtec drag gen 3 kit runing a FMU, missing link, and Vafc

bad map sensor?
any input?
thanks

 

sounds like possibly hitting boost then vac. then boost then vac. etc... casues your missing link to screw up. After sitting for a second w/ no boost it goes back to normal then ou can boost to 7. try driving normal no boost for a while then try and boost in just 3 gear. This is just a thought.

 

Thats a thought. will try it and see what happens. anyone else

 

missing link is probably a bit dirty... clean it and see if that helps.

 

Nope and nope. its brand new and i cleaned it. and it does it from a seady vacume to full boost
this sucks

 

this is easy, you cant run a missing link with a vafc, the vafc modifys your map sensor voltage. having the missing link on there is causing all ur problems. pick either the fmu w/ the missing link, or just the vafc. your welcome

 

Hey guys,
The problem is fixed thanks for all the input. The problem was the VAFC was bad. In the process of messing with it it turned off and never came back on. swapped it with a new one and it works just fine. go figure it was less then a week old. and yes the Vafc WILL work with a Missing link. but thanks for the useless, incorrect info platty9.

Everyone else thanks much

 

Does that mean my VAFC is bad?? it works fine.

i have the same setup and im getting code 3.

fmu missing link vafc

 

I personaly had a defective VAFC in my car.

 

tell me how your car can run corectly with a missing link and vafc. a vafc modifies the map sensor voltage fooling your ecu into thinking there is no boost present. if u have a missing link on there then your vafc wouldn't scale the map sensor voltage correctly.but yeah i guess i don't know what i'm talking about. don't listen to me. post pics of your motor when u destroy it. just trying to help.

 

hey i notice you wrote something about the vafc not working with the missing link awhile ago...just wondering would it work with 5 check valves instead of using the missing link. Currently i am having problems at 5500 rpm...the map sensor check engine light comes on and there is a burning smell so i just shut off the car so it resets the check engine light.

The setup:
1995 GSR with Greddy turbo, VAFC, hayama cam gears,internal wastegate, vortech rising rate, and intercooler.