ok lately i have been throwing this code everytime i go into boost.
0803
Manifold absolute pressure sensor circuit fault.


unsually when i gun it. any idea what to check. i am absolutly lost. guy at work is saying its coming from the boost sensor. others say its something else. this code us to come up once in a while. but lately everytime i get on it on the freeway i pop this code.

any one have any ideas.

99 maxima
sc
3.125 pulley
no particular speed in which this occurs.

any ideas will be appriciated.

Thanks
Frank

 

it has nothing to do with the tranny man....

 

I get this code all the time, but lately I have not got the code, when I get it is because a wire came loose or something, example, one of my wires were disconnected from the MEVI and as soon as I connected it I stopped getting the code. Any open wire will throw that code. The sensor thats at the corner of the elbow that comes loose as well but thats the ambient air temp sensor and when it doesnt get a good connection because my **** is rigged up it will also throw that 0803 code theres my two reasons for the code and I usually fix it right away.

 

see if replacing just that connector may help...that cant be too much $$$ for it...and let us know...I remember you having that thrown twice at Fontana...not last time but before that...

 

i tested the sensor it is bad.

POS sensor cost $160 my employee cost.
stupid POS they go for $250 list. :O

this is retarded. ill let you guys know if it goes away.

 

Any updats on this , I am throwing the same code

 

the code does not pop up as often after the 5 spd conv. but im not driving my car as hard either.

talking to a few people i guess it senses something wrong when it sees boost. well atleast thats the first thing everyone says. until i say 80% on the boosted guys on the org never see this code.

another thing i heard was that its a ghost code that is thrown when you have a bad KS. not to sure about that. i forgot where i heard that one from.

right now im just living with it. it does not harm anthing that i noticed. i just reset it when i get the chance. its annoying though cause your never sure what is really wrong until you chekc the code. i think the fed spec guys have it better the sensor is like $70 dollas my cost. cali spes its liek 160 my cost.

 

I use to 0803 when something electrical got disconnected. Like the power to the relay to the MEVI. My ambiet air temp sensor was not fully seated and I that would also trigger that code to come on. I fixed that problem and have not got another one. I am now boosting close to 10PSI once again and no codes up to date knock on wood.

 

strange.....does that mean that there is something wrong with my air intake sensor. or boost (map) sensor??? loose connection maybe i sould close the gap on all the electrical connects. the only time i get that code is under heavy acceleration. usually in 3rd auto or 5spd.