Engine cuts off/dies at WOT.. :(

[Aust162]

Hey everyone, I've just got my conversion running. I've put an EP82 GT 4EFTE into an EP91. (fyi Ep91 originally have a 4efe)

I've set the timing at 10 degrees, its running the stock 4efte ecu, stock turbo injectors, new filters and fluids, stock 4efe fuel pump.

The car idle's smooth and drives well. it comes onto boost (6psi set atm) and makes all the right noises.


The problem is i cannot floor the gas pedal! as soon as i stomp the pedal (in any gear at any rpm) the engine lights comes on, the car stops abruptly (feels exactly like boost cut on 3sgte, 1jz etc engines). the motor is still running, it just cuts out until i lift my pedal, then i can drive it like normal.

to build boost i have to gradually feed in the throttle and slowly slowly rev it up

the engine light only stays on for 5-10secs and it WILL NOT store the code.


If i floor the throttle while the car is idling stationary it will do the same thing. so the issue is not really load dependant.if i keep the throttle down and dont release it, the car actually stalls out.


Anyone have problems like this? any help appreciated. i just want to hoon in this car lol!

[dumbass]

Make sure u have battery backup power to ecu
This might be y its not storing the codes

[oldcorollas]

TPS issue?

[Aust162]

Dumbass:cheers, I have battery backup working . I had water temp and knock sensor codes coming up when I left these connectors unplugged.

Oldrollas; I think it is tps or throttle body issues. As soon as the throttle body butterfly is wide open , it cuts out. Almost like it looses voltage or resistance to the throttle sensor. I have a spare tps to try and ill make sure it's adjusted/calibrated correctly

[Hen]

I'd also look closely at TPS. I'm not sure what a 4EFTE runs, but having the WOT and IDL wires swapped could send it into overrun fuel cut at WOT.

[Aust162]

I found out what I did wrong. For some reason I confused myself on the pinouts when making the loom. I connected the map sensor pim wire and vcc tps wires together at the ecu plug. I think this made the voltage rise (5v sensors)at full throttle which triggered the map sensor into thinking it was hitting boost cut.. Either way I ran a new wire to the tps and connected it to the right ecu pin (pin 17 on 26 pin plug). Pin 18 is for map sensor. Car runs good now

[dumbass]

That's similar problem I ran into many years ago when wiring a honda

The shop had plugged the map sensor plug into tps and tps plug into map sensor
Dumb fk honda did a bad design

So map sensor signal was climbing as u open throttle then it hits map sensor cut like boost cut but for non turbo
Took me awhile to figure it out

[Aust162]

That's similar problem I ran into many years ago when wiring a honda

The shop had plugged the map sensor plug into tps and tps plug into map sensor
Dumb fk honda did a bad design

So map sensor signal was climbing as u open throttle then it hits map sensor cut like boost cut but for non turbo
Took me awhile to figure it out

ha! far out man. very similar to my problem. as if honda didnt make a different shaped plug connector to avoid things like that happening.

[oldcorollas]

I found out what I did wrong. For some reason I confused myself on the pinouts when making the loom. I connected the map sensor pim wire and vcc tps wires together at the ecu plug. I think this made the voltage rise (5v sensors)at full throttle which triggered the map sensor into thinking it was hitting boost cut.. Either way I ran a new wire to the tps and connected it to the right ecu pin (pin 17 on 26 pin plug). Pin 18 is for map sensor. Car runs good now

so apart from WOT, it didn't run too bad on TPS -based load?

[Aust162]

It ran pretty much spot on which was really strange.. it had a slight hesitation on low/medium load around 1800-2500rpm.

-based load.?