Ok can i a gm 3 bar snesor with the fd stock ecu?



and i idle rich, and under load it leans out, and back fires. if i rev slowly it will go untill about 4k rpms and the go lean and backfire.

if i rev it fast it will just backfire pretty fast.



any help would be great.



Thanks a ton

Robert

 

OK, I think what you are trying to say is that you are using a gm 3bar MAP sensor with a stock ecu and having problems and you want to know if you can use the GM sensor or not.



The answer to this is that you can not just use the GM 3 bar sensor on a stock FD ECU because the voltage scale is completely different. You need the stock sensor back in there and all will work fine for ya.



Just out of curiousity...why did ya get the 3 bar sensor if ya have a stock ECU anyways?



Bob

 

isnt backfire usually caused by running rich?

 

that was my understanding of why our cars backfire so much

 

no no... i told him the 3 bar sensor works. i didnt know if you could use it with the stock ecu (i figured u cant but thats why he posted) his car currently has a slightly burnt stock fd sensor. i dont have a stock one to supply to him so thats why hes wondering if he needs to replace it or not...



at idle it is rich, higher rpms, it is lean after it backfires.



hes looking for a solution to this, he has intake and full exhaust on a stock ecu, one easy fix id say is get a power fc, but money makes it difficult to get one.



is the map sensor causing his rich condition and backfire? or is it that and the stock ecu not being able to keep up with his mods?

 

by burnt do you mean like engine fire burnt? Have you checked to see what the voltage is that the sensor is reading?

Sounds like the map sensor is f---ed, but check it out.

Also, by full exhaust is that dp mp cb? He should upgrade his ecu soon or atleast get a good boost controller and keep that boost around 10psi, but he will still be in a risky area.

Check the map sensor voltage and let us know if it is within spec.

If it isn't I may be able to sell ya mine cheap, I just gotta check with nopistons93 to see if he still needs it.



Lata

Bob

 

I'll trade you my perfectly functioning stock one for your 3bar.

 

funny part is that the oem mazda probably would cost more than the gm

 

ok i'll check the reading, today i replaced the mid-pipe with the stock cat, still backfires. if i step on the throttel fast it just backfires and goes lean, if i bring the rpm's up slow then it will hold untill about 4k rpms, then it leans out but with out a backfire. i have a manual boost controller and am keeping it about 7psi. and yes it was an engine fire, replaced everyhting axcept the MAP lol. oops. i'll check the voltage tomorrow and get back to everyone.



One other question. on the lower fuel rail ( if anyone has replaced it or put a new harness they will know what im talking about) the two plugs that plug into the injectors... the wire with the white stripe going around the two wires, does that go on the left of the right? i put it on the left if you standing on the driverside.



thanks again.

Robert

 

well, even with a power fc, you still have to program the ecu to run a 3bar sensor, so i would higly doubt it if your car's stock ecu will be able to read the 3 bar sensor