Rb25 Won't Run With Afm Plugged In

[Simon-S14]

hey this 33 im working on i cant get it to run with an AFM plugged in at all.. runs fine with AFM unplugged but the min you plug it in it stalls and wont start, fires but wont run. has a known working afm on there and then tried the one off my other car.

have searched for air leaks.. nothing found.. any suggestions?

[discopotato03]

When we fitted a Z32 MAF we had the outer two wires wrong way round and it was a bit like that . Is it std or been played with ?

A .

[Simon-S14]

Stock loom, stock Ecu. All that's been done is an engine swap

[GTSBoy]

Try another AFM. The faulty one might have cracked joints or a really dirty sensor.

[Simon-S14]

Nah the one I tried works in my car but not this 33

[AngryRB]

series 1 and 2 have different air flows i think, what colour is the tag?

[Simon-S14]

Green sticker. Its a s1 loom and Ecu

[WMDC35]

engine swap/conversion? was car running with these elecs before engine swap? not something unusual like ecu plug not pushed in properly?

[89CAL]

series 1 and 2 have different air flows i think, what colour is the tag?

I dont think they are interchangeable however. Different plugs

[WMDC35]

I dont think they are interchangeable however. Different plugs

yeah, s1 green sticker 22680-02u00 5 pin plug (usually uses 4 pins), s2 pink sticker 22680-31u00 3 pin plug

[Simon-S14]

engine swap/conversion? was car running with these elecs before engine swap? not something unusual like ecu plug not pushed in properly?

Just another motor cause previous one blew up. Ecu check is next on cards

[GTScotT]

pin trace, my money is on damaged wiring

[Simon-S14]

so frustrating.

continuity test on the power, signal and ground wires all tests out ok, with the engine off afm plugged in its reading 0.5 volt on the afm... if i blow into the afm it goes up in volts to 1 volt ish before i run out of breath haha. when i crank the car it doesnt drop volts on the power side and on the signal sie it goes up slightly with the extra air its sucking in while cranking.

tested both at plug and ecu. fine.

im suspecting its possibly fuel pump at this stage. with afm unplugged and the fuel return line off the hose im getting no fuel coming out the rail when idling.. when i raise the revs some fuel comes out but then as i raise the revs til the point it cuts out with no afm plugged in (about 2500 rpm) not much fuel is coming out again.

am thinking dodgy fuel pump, which is what caused the previous motor to blow. however why wont it run with afm plugged in?!

[Dan_J]

with it unplugged the default maybe at certain revs to the so injector duty goes up etc so it just idles on the bad pump, when you rev more it leans out and stalls?

just throwing ideas around

also try unplugping the ecu coolant sensor

Edited September 3, 2012 by Dan_J

[DVS JEZ]

Does it blow alot of black smoke?

I have an s13 just come into shop thats had an rb25 wired in. Similar issue's but choofing black smoke, found the tps wiring has 5 v to signal so ecu thinks its foot flat

[Simon-S14]

nah no black smoke\

solved it... its a f**ked fuel pump.

got a mate to unload a can of areostart into the AFM while i was cranking it and it runs and revs as long as there is an areostart supply haha, fuel pump lacks pressure