1jz overfuelling ... any suggestions?

[1jzfanatic]

possible reasons for a 1jz to overfuel
i have had it with the TERRIBLE economy that im getting

its a 1jz cressida, stock boost, stock everything, manual,... 3 inch exhaust from cat back, stock turbo's(although theyre smokey sometimes) stock jzx81 exhaust from turbo's to cat.


sometimes it gets so bad that im changing gears and flames are shooting out the exhaust... and it misfires on idle, i originally thought it was spark, but not i believe its cause the cylinders are so full of fuel, they just CANT fire....(it mnakes me believe that cause i can see fuel leaking between the gaskets on the back of the turbo's when it misfires badly)

any ideas / similar experiences? ive tried searching, but no deal.

cheers

[EldarO]

check your MAP sensor vac line.

[1jzfanatic]

ok i will check it out. failing that, any other suggestions?

[JZX083]

coolant temp sensor for the computer???

[JZA70 R]

if its not throwing any codes put it on the dyno to see how its actually running. (check AFR's)

could have a problem with injectors or your fuel reg...

[jzx81mx83]

It could be many things man
but try the map sensor first,Then Give the engine temp sensor ago ( the Green plug on the water neck ) unplug it and if the car runs worse then u no its working But 1jz's dont have a cold start injector and they rely on the temp sensor to let the ecu no when its warm enough and if the ecu thinks the engine is cold it will keep the mixture Rich as and cause it to fuel up.

One or a few injectors could be sticking open
What cylinders is it missfiring on ?
Or the O2 sensor could be no good as well

Failing that ure ecu could be F#$@%d man see if u can borrow another one and see if that works.

i had the same problem with a 1jzgte at work and it was the ecu

Cheers nick

[Herus]

Sounds like an ECU to me.

My car was holding injector 3 and 5 open, flooding them with fuel.