MR2 MAP Sensor problem, i had problems Options

[Celiracer18]

so today i received my 2BAR MAP sensor from a 93 MR2. When i got it put in and started it up i got this-

i checked the wiring diagrams and they should be the same so im not sure what to think. Any suggestions?

BTW heres a pic of the 7A bracket modified to fit the 3S sensor

it wasnt too hard to bend it to the right position but the MR2 bracket might just bolt right on im not too sure.

This post has been edited by Celiracer18: Apr 11, 2007 - 5:56 PM

[hurley97]

I'm surprised Manny hasn't explained it to you the way he explained it to me yet... it went something like this...


they work by sensing vacuum and/or boost using voltage then depending on that reading tell the ECU how much fuel to add or subtract. the 7A MAP sensor and the MR2 MAP sensor read off the same voltage scale, but the 7A sensor only senses vacuum while the MR2 sensor read both vacuum and boost (so trying to fit more in the same scale it's obviously more compressed/less accurate/harder to tune than the 7A).

(I'm making up numbers for example purposes) so when your 7A sensor reads 3.5v it tells your ECU your at 10psi of vacuum and tells the injectors to take out 7% fuel. but when your MR2 sensor reads 3.5v its at 10psi of boost and tells your ECU which isn't sure what to do with that information. thats why you have to add/subtract fuel with the SAFC so the SAFC tells the ECU what to think.

so *in theory* if you're using a MAP sensor thats twice as big, putting in injectors that are twice as big should make the car run normally... although I'm pretty sure that won't be the case


...or at least thats what I got from what Manny told me. does that make sense?