Hi All,
I’ve searched through the forums but have had no luck. Can anyone tell me why there are two MAP sensors ? From the forums, it looks like MAP B handle boost cut etc. So which determines engine load ?
I am looking at connecting and intercepter to change boost limit and possible A/F mix
Thanks
Different function between MAP A and B
- James
- Moderator / Donating Member
- Posts: 3092
- Joined: Wed Apr 09, 2003 1:59 pm
- Location: Putaruru
- Contact:
Map A sense vacuum and small boost signals and map B sense low vacuum to high boost levels, they have some overlap which the computer checks, and if it isnt right then it throws an error code.
A fuel cut defender works sweet if you put it on Map B, an air fuel hack thingie should work aswell on map B but youll only be able to change the mixtures on boost.
A fuel cut defender works sweet if you put it on Map B, an air fuel hack thingie should work aswell on map B but youll only be able to change the mixtures on boost.
Thanks for the info. Had a feeling that would be the case based on the pressure/output curves in the manual. I actually thought about hacking the software on the ECu. Done this will a saab turbo I used to have. However, using one or more intercepters (Silicon Chip kits) will be much simpler for now.
Cheers
Cheers
- James
- Moderator / Donating Member
- Posts: 3092
- Joined: Wed Apr 09, 2003 1:59 pm
- Location: Putaruru
- Contact:
Both map sensors go through some funny thing in a plastic block and then go through an SMD LM358 buffer and then through a 1 of 8 analog multiplexer to an 8 bit ADC and then via digital to the MCU, thats the best I can tell from tracing the paths on the ECU.
MSM5204RS is the ADC, TC4051BP is the analog MUXer, The 358 has a funny chip number on it too, starts with J.
If you are interested in doing some research on the ECU function I have a whole pile of datasheets for some of the chips and a description for every IC in the ECU.
MSM5204RS is the ADC, TC4051BP is the analog MUXer, The 358 has a funny chip number on it too, starts with J.
If you are interested in doing some research on the ECU function I have a whole pile of datasheets for some of the chips and a description for every IC in the ECU.
Who is online
Users browsing this forum: No registered users and 135 guests