Ka24de swap wont rev up

[wdyrland]

I did a ka24de engine swap into my 1990 240sx. i had to set the intition timing and it seems to be all timed up but it wont rev up past 2500 rpm unless you start it up when cold it will rev up for a couple seconds then stop. it has a small exguast leak but i dont know if that would affect it



AAny ideas will be usfull. i am at the piont where i am willing to try anything.I thought it might have been the MAF sensor but i got 2 of a 240sx at the junkyard and a altima for a yard aswell and that did not affect anything. i can unplug it and plug it in when its running and it does not change anything.



thiere was one clip that was brown and had green wires to it that came out of the fuse box but i couldnt find anything to plug it into.



the plugs are black and it is really smoky.

here is a video link to show how it is running

http://www.youtube.com/watch?v=_8EV2ws8Tws

Modified by wdyrland at 11:58 AM 4/1/2009

Modified by wdyrland at 12:01 PM 4/1/2009

Modified by wdyrland at 12:02 PM 4/1/2009

Modified by wdyrland at 12:03 PM 4/1/2009

Modified by wdyrland at 12:04 PM 4/1/2009
Modified by wdyrland at 12:08 PM 4/1/2009

[wdyrland]

BUUMP

[wdyrland]

any suggestion is helpful...i have no clue what to do

[akira2_03]

double check all ur plugs are pluged in properly and check your timing to make sure it is proper and distributer wires are in the right spots. and double check ecu wires are all correct. i think its the distributer. plug wires may not be in correct spot.

[airman86]

i'm assuming there is no check engine light?

you say unplugging the maf does nothing? in most of my experience with other vehicles the cars will die as soon as you pull the maf...

in the video, did the engine seem to be hitting a rev limiter or was that you bouncing on the gas pedal?

honestly i'm going to say maf, but if you've tried 3 including the one that was on there to start, I don't honestly know. the fact that you unplug the maf and it doesn't make a significance says something strange to me though.

edit: 100th post....grats to me :P

[wdyrland]

okay i will retry the timing agian just to make sure and in the video the car is approx 2500rpm when it was bouncing like that it was doing it by itself...

also when i first start up the car when it is cold it will rev right up but shortly after drop down back to bouncing at 2500 rpm.

could the ecu be malfuctioning?

[wdyrland]

so i bypassed my MAF sensor and my car would rev right up but it wouldnt idle very well.

if i opened it up it would run good.

any reason why maf wouldnt be sending a singal

[airman86]

bad maf/bad wires/short somewhere

[JesterX18]

If your exhaust leak is before your O2 sensor then your O2 is going to dump lots of fuel into your engine because it reads as lean. (excess air) Its going to keep dumping fuel but your lean reading is still going to be there. That would cause blackened fouled out plugs.

[dopes13]

I recently swapped a KA motor into my 240 because i blew my original motor. It seems to me we are encountering the same problem. The car would SOMETIMES run fine loking at the tachometer. However SOMETIMES it will "bounce" at 2500 RPM not letting it go over. Did you ever figure out what the problem was? I also checked my MAF spark plugs and timing. My spark plugs also get really black and i have the repeatably buy new ones and keep trying over and over. Im really stumpped and getting really annoyed. The most annoying part is when it doesnt seem to have that restriction the car runs perfectly fine -____-;;

[kouki4silvia]

dude it sounds like a maf issue. trying asking for someones maf hook it up if it works you know you need another one. if its still doing the same thing your gonna have to check your wiring. are the plugs wet or dry? remember when the maf is screwed up the computer trys to compensate by dumping more fuel which will cause you to run rich. this is what you should do:

check o2 sensorgasketsand wiring.

did you do the swap yourself? could be your wiring....

bad maf equals no rev thats one and the trick with mafs ive learned is if there not grounded properly you will see those symptoms and bottoming out.