MAP sensors generally

alexander · Post by **alexander** » Thu Feb 19, 2009 2:24 am

i note that the MAP sensor in theMJ can be purchased from digikey in the US for USD10. in australia, the part will cost you AUD30. a delco GM type 3 pin MAP sensor found in your average american car cost about USD60. a new Denso MAP sensor for my partners 1994 toyota corolla? AUD500!!
i had a second hand one put in yesterday when the car was being repaired....

the delco, and the Denso sensors are both 3 pin sensors. they both have a Vcc supply ( which i think is 5v) an earth, and an output which varies from 0-5v. in short, they seem to be essentially identical save only for a different plug, and a massive price difference.

question: is there any reason why a delco sensor could not be substituted for the denso one?

regards
alexander.

Post by **brentp** » Thu Feb 19, 2009 4:22 pm

I've been thinking of providing a low cost 'external' map sensor. Perhaps this might be a good alternative to the expensive OEM modules, as you allude to? Once concern is making it weather tight for mounting in the engine bay. This kind of stuff always increases cost and complexity. In any case, feedback is appreciated.

MartinM · Post by **MartinM** » Thu Feb 19, 2009 4:38 pm

I have had good success wiring s/hand OEM MAP sensors into a TPS MJLJ - with of course, not being able to use a throttle position sensor at the same time.

MAP or TPS inputs are just a voltage that has to arrive at pin 11 of the processor and represent engine load...

alexander · Post by **alexander** » Thu Feb 19, 2009 6:22 pm

brentp wrote:I've been thinking of providing a low cost 'external' map sensor. Perhaps this might be a good alternative to the expensive OEM modules, as you allude to? Once concern is making it weather tight for mounting in the engine bay. This kind of stuff always increases cost and complexity. In any case, feedback is appreciated.

brent, i am not sure which one you think might be a good alternative? the MAP sensor in the MJ IS the really cheap one; the delco sensor, which is of course OEM in GM cars, is almost as much as the whole MJ kit, and the Denso sensor is just plain robbery. i say "the delco/denso one" even though there are many different part numbers, because it seems to me that they must all have almost identical characteristics ie 3 pin, 5volt, 1 bar. how could their outputs differ??

martin, do you have some insight into that? if you have already been wiring OEM MAP sensors into TPS MJ, you must know more. do tell! (gosh, dont you feel important using all these esoteric acronyms?).

regards
alexander.

BRUCEROE · Post by **BRUCEROE** » Sun Mar 07, 2010 3:19 am

I started using a very compact MAP sensor, an 8 pin surface mount chip with a small side port. I picked one that goes a little higher than 1 BAR, puts out about 4 V at 1 BAR. Cost $7.77 in small quantities from MOUSER; MPXAZ6115AP. I believe the technology is the same as automotive units. I use them to repair the 70s Cad ECUs needing a replacement for the mechanical linear transformer unit, which fails a lot. An op amp rescales the output for the Cad ECUs. Bruce Roe

BRUCEROE · Post by **BRUCEROE** » Sun Mar 07, 2010 3:20 am

I started using a very compact MAP sensor, an 8 pin surface mount chip with a small side port. I picked one that goes a little higher than 1 BAR, puts out about 4 V at 1 BAR. Cost $7.77 in small quantities from MOUSER; MPXAZ6115AP. I believe the technology is the same as automotive units. I use them to repair the 70s Cad ECUs needing a replacement for the mechanical linear transformer unit, which fails a lot. An op amp rescales the output for the Cad ECUs. Bruce Roe