KA24E sputtering?

[socaldatsun]

so I am almost done with my KA swap into my 521 but only problem is that the motor keeps sputtering and bogging once its on the gas.

This motor has been nothing but problems since day one. when we cranked it over for the first time the rods bearings were knoking. Then after that the wire harness was butchered up and verry dried out, so we pulled a better one from the yard.  changed gaskets and timeming chain. So ones everything is sealed and ready to drive this last issues pops up. Motor idles fine but once you start to rev it up a little the RPMS pulsates/sputters. When it comes to driving in first it just completly boggs. The motor is all stock, stock harnes with emissions deleted and a walbro 255 fuel pump.

So heres what we've done Changed out the injectors, the maf, Distributor, Coil pack, TPS, ECU with a stanza.

heres what we found out. When we disconect the top plug from the TPS it stops Sputtering, It also stopped with the stanza ECU. The maf, dis and injectors made no diffrence: although we did find one of the injectors sucking in air yesterday.

We checked the timing 3 times already aswel. this has me stumped.

one thing i am going to try is to get another 240sx ecu and a nother fuel pump to see if that does anything.

heres a video of whats going on.

 

 

[flatcat19]

although we did find one of the injectors sucking in air yesterday.

 

 

^

Ding.

 

Suck. Squish. Bang. Blow.

Which is awry?

[DAT510]

My 240 was doing the same thing, it turned out to be my fuel pump and some vacuum leaks.

Yeah make sure everythings sealed properly. I put a hose to my ear and use the other end around the engine to look for leaks.

[jesusno2]

First off what top plug on the TPS are you talking about? I had a similar problem with my ka it had bad throttle response and a hiccup off idle etc. my distributor was off a notch. And by a timing light I was able to dial it to 15 degrees,but it just wouldn't advance correctly. Ran pretty horrible really. Test your parts before you swap em. Sometimes you will swap good for bad and chase your tail even longer.

[socaldatsun]

Theres two plugs on te tps, top one that dangles off of it an one directly onto the body. So finally got time to pull that leaky injector and found out that the plastic nub on the bottom part was complete broken off. After replacing it and trying to drive it the motor will still bogging down, all o a sudden my motor will turn on strong for a few seconds ten completely shut off. Starting to think its a bad sensor or my fuel pump( highly doin since its a new walbro 255)

[sal]

Sound like your O2 sensor is done for i had my truck do the same chanched it and problem solved only 25 bucks.

[datzenmike]

Try it when the motor is cold and the O2 not in operation yet.

[socaldatsun]

Te o2 is new but the wires did seem a little crusty. Think I'm not getting a connection

[jesusno2]

Top plug on TPS is for automatics