93 240sx KA24DE Issues at idle

[I Am Chris]

Okay so for starters I have a 93 240SX with a pretty much stock KA from a 91. The only thing not stock would be the Test pipe instead of the Catalyitic converter.

As of now my car has issues that are most noticeable when the motor is warm. I have a hunting idle/rough idle, back fire through the exhaust ( believe I have a leak at the header ), running rich, And a shake in the motor. Also when the car is running it has a sputtering sound from the exhaust.

What I have done so far are as follow. I have checked compression and am at around 155 on all cylinders, I have changed my CTS, checked my MAF, fixed an exhaust leak at the test pipe, checked for vacuum leaks with starting fluid.

Not sure if its of any help but the car is a auto to 5-speed swap and running an auto ECU.

Tomorrow I am going to to be checking the timing and cam position. Also will try to fix the possible leak at the header. Any input from you all is appreciated. Thanks for your time.

[rps13ka]

from what i've read, the issues you're having are common for auto to manual swaps with auto ecu's. something about certain codes the transmission is giving out not matching with the codes in the ecu so it goes a little haywire. biggest and most important solution would be for you to find a manual ecu and swap it out asap!!!. it even give you a cel on occasion because of the overdrive feature not being held accountable for in the auto ecu. try that and see how it works out.

[PapaSmurf2k3]

Has it ever run correctly for you?

[rps13ka]

i personally havent done it yet but ive done an @ssload of reading up on this because im planning on doing a 5 speed swap myself. so after i found instructions, i started looking for common problems and issues doing the swap and rough starts with an auto ecu.


something to live by if you are a DIY kinda person: learn anything and everything that you can about what you're gonna do because, anything that can go wrong, will go wrong. so if you ever run into one of the known issues/problems, you'll know how to handle them.

[shiro_neko]

Look into the neutral switch.