KA24DE Hesitation Low RPMs Problem

[Drift N Dragg]

I bought a 1992 240sx with a KA24DE.. Runs good, Idles smooth. But it hesitated when you give it alittle gas between 2k and 3k .. Sometimes if I let off while crusing on the freeway it will do it too.. Also No off the line power.. Has Wonderful pull @3500 On up.. I dont think thios makes a difference but last owner put S14 Injectors in the car. But i did a complete Tunes up.. Oil, Plugs, Wires, Cap, Rotor, Fuel Filter, Air Filter.. and same problem.. Checked the Timing and its dead on.. 20 Degrees BTDC, Clutch is good.. Wondered if anyone could be of Help Please..


Thanks!:eek3d:

[Drift N Dragg]

No Ideas at all huh

[BigVinnie]

Check ecu codes.
Check knock sensor.
Check TPS, possibly adjust TPS.
Check fuel filter, possibly change fuel filter.
Check MAF and possibly clean maf.
Check fuel pressure.

[240sxScores]

Check Fuel pressure

Replace with walbro 255.

Ive been running one with stock fpr for like a year now.

[98s14inaz]

Are you sure timing is right? Try advancing it a little and see if it improves.

[SoguRacing]

i believe the s14 injectors flow more than the s13 injectors...not sure if we're talking domestic injectors or JDM injectors. please be more specific. the bigger injectors could be the culprit for your hesitation...too rich.

[Drift N Dragg]

Can I run a 255 Walbro and not run rich?

I advanced my timing 5 Degrees, then 10 degrees... I gain alot of power from 1200 to 3500 RPMS .. BUT I lose all power after that.. Like The engine does not want to produce..

I am not sure what S14 injectors, I bought it like this.. He just said S14 injectors..

I am also burning threw gas like no tomorrow.. maybe 65 miles to a 1/4 tank..and thats doing 70 mph on the freeway.. (I travel 75 miles one way, my Old 240 could usually go 90 to a 1/4 tank)

Also I am not throwing any Codes.. I changed Fuel Filter...

[BigVinnie]

Can I run a 255 Walbro and not run rich?

I advanced my timing 5 Degrees, then 10 degrees... I gain alot of power from 1200 to 3500 RPMS .. BUT I lose all power after that.. Like The engine does not want to produce..

I am not sure what S14 injectors, I bought it like this.. He just said S14 injectors..

I am also burning threw gas like no tomorrow.. maybe 65 miles to a 1/4 tank..and thats doing 70 mph on the freeway.. (I travel 75 miles one way, my Old 240 could usually go 90 to a 1/4 tank)

Also I am not throwing any Codes.. I changed Fuel Filter...


It would be nice to know the injector flow rate. If they are s14 sr20det injectors your engine is way to rich. All ka24de injectors are 270cc.

If it's not your injectors. Then you will want to check your TPS voltage, clean your maf, and possibly change your O2 sensor.

[Drift N Dragg]

I will Check my TPS Today sometime... and see what I come up with.

[Bigsyke]

Its your KS

Unplug the sensor from the main engine harness and insert I believe a 1M ohm resistor;

it should then run great

[Drift N Dragg]

Its your KS

Unplug the sensor from the main engine harness and insert I believe a 1M ohm resistor;

it should then run great

OK here it comes.. :mepoke: what is a KS?:eek3: and where is it located?:hyper:

[Leetheslacker]

OK here it comes.. :mepoke: what is a KS?:eek3: and where is it located?:hyper:

knock sensor. its on the block under the intake manifold.

[Drift N Dragg]

And where am I placing this 1 Ohm resistor? on the lead wire? and for the stupid, why does that fix my problem?

[Drift N Dragg]

Ok, I did the Resistor, didn't fix the problem. Replaced the the TPS, didn't fix the problem.. Could it possible be my Vacuum lines? I found a sweet spot on my throttle. if i push like a 1/4 way down I can go threw the RPM's fine. but if I try to go beyond that the car bogs like it aint got no power...

[rc1honda]

Please when you firgure this out please post it. Im having a very similar problem in s13 SR. It idles fine and revs freely past 3,000 rpm. But if i just push on the throttle and keep it at a certain point it will hesitate like it's not getting fuel or spark. Also it will almost be like a hunting idle. I will keep the throttle about a 1/4 of the way depressed and the revs will go up and down and sound like a hunting idle. If i rev the motor and pump the throttle it will rev freely and will pull strong. It's just when the throttle is 1/4 to 1/2 way depressed and you don't pump the pedal that it goes flat. I have a walboro 255, and sard FPR. I also have a pfc thats needs a tune, but the only thing is that the car was still doing this when i had a safc tuned with the dyno. So im kinda at a loss.

[Drift N Dragg]

OK.. Now the problem has INCREASED... The car wont stay on.. Starts right up and then 2 seconds later dies.. BUT if I take off the MAF it will stay running..... I SWAPPED the Maf same problem. Also the Injectore does not look like one that goes to this car.. can someone Identify the rail? I hella need help this is killing me.

http://i15.photobucket.com/albums/a373/sugerrrbear/Injector2.jpg

http://i15.photobucket.com/albums/a373/sugerrrbear/InjectorRail.jpg

[fueled by hate]

try cleaning out your egr ports and verify that the egr is working properly via the diagnostic tests in the fsm.

[wings_s13]

check your spark plugs bc if you are running rich then it could be dumping way to much gas and could be falling your spark, get nkgplugs and a new better coil try that. good luck.

[Drift N Dragg]

CAN YOU BELIEVE IT!! THE DAMN EGR!!! Talked to my Father.. Long time mechanic.. told me to spray penetrationg fluid threw the egr lines and rev.. over and over .. I did it 10 times.. its got better each time.. Now all power restored.. cleaned out all the carbon build up... EGR cause all those damn problems.. after I changed: TPS, MAF, Fuel Pump, Fuel Filter, Cap, Rotor, Wires, Plugs, Air Filter..Traced all wires, Vacuum lines... can we say HEADACHE.. but I am happy again.. thankyou everyone for your input on helping me trace this down.. ZILVIA and my DAD ROCK!!!!!