ka24de not willing to rev past 4000rpm

[neverlift]

zerothread/273004

a breif run down of the problem, I got a jump the other day then went for a ride, my car wouldnt go past 4000rpm, this has been like the 4th day. I pulled codes, and got one for the speed sensor curcuit. I cleared the codes and it hasnt came back up, but the car still will not rev beyond said rpm, I can manipulate it past 4k but it doesnt want to go. this is a 90 240sx with a ka24de. Its kinda a hybrid, has a sohc maf and ecu, running the de motor and injectors, no thats not the problem, its been fine for months....

Thank you guys.

[My RB25]

Speed Sensor = CKP (Crank Position Sensor), is 4,000 rpm limp mode for the 240? If the sensor isn't bad I would check your wiring, make sure it isnt broken or coroded anywhere, also check the conectors for corrison.

[neverlift]

so code 14 caem up again for the Vehicle Speed Sensor Circuit so its the one on the transmission? time to rob the sohc transmission

[edward644]

hahah been there.............. i replace every thing that had to do with spark and fule.... make it short it is going to be the fule pump.... you lose fule PSI when it gets to 4k. I bet you were wasting lots of gas too... So i just end up getting a s2000 fule pump and boom work better then stock

[neverlift]

it a walbro.... on hotwire mod... maybe I'll switch out the relay and try that... I'm gonna be pissed off cause it doesnt even have 10000miles, its been on 58psi but that shouldnt be an issue, I for some reason dont think its the pump, my wideband reads rich straight into it, and stays rich till I decel.

[My RB25]

Ohh the VSS, I thought you mean ESS (Engine Speed Sensor). Usually the VSS is mounted on the rear of the transmission, but I could be wrong.

[neverlift]

yeah its the vss, it came up again so I unplugged it and re wired the thing, it was chop/splice job from previous previous owner, IDK its very strange, I needed yet another jump this morning, and the car has started four more times, I'll be going to the parts store for an alt test today... someone mentioned the fuel pump, I tested the pressure vs rpm it drops when boost falls off(tunrs into vac) and psi goes to normal for vac. I'm lost a bad pump normally is just that, bad meaning car wont start.

I replaced maf cap and coil as well as fuel filter(it was a good 300zx one) I'll be swapping my relay at the pump and hope thats it, as well as getting the sensor from my sohc transmission(vss) I'll be rewiring some of this rats nest I have(I would hav ebought a nother damn harness knowing what I know now) any more ideas guys need this fixxed.

[neverlift]

ok guys a blown VOLVNO IC is the culprit. end thread I'm pissed it only held 8psi and blew me. so does volvo