car wont rev over 5000rpm

SON240sx Automotive
21

Parts replacer? No. Not by a long shot.

Diagnosing via internet is stupid hard.

I say CAS because I have repaired many cars (mostly Honda’s) that have had early cut off problems. 3k, 25k, 45k, and 5k.
90% of them has been crank sensors. the other 10% have been TDCS.

Yet, I would trace your CAS wiring straight to the ecm and grounds.

22

  1. check base timing

  2. check the tps for holes in the sweep

  3. “turbo still spooling” is not a definitive way to rule out a fueling issue

are you able to check your fuel pressure under load? what fuel pump? stock? walbro? new? used?

  1. since you changed the ignitor and plugs, try a different sent of coilpacks. also, it’s possible (but unlikely) that the coil drivers are weak on your ecu. try another ecu.

swapping parts is part of diagnosing… theres nothing wrong or “less technical” about it at all

23

good points mike, when farms called me a few days ago on this the first thing i asked was if the motor was taken apart, cuz i thought maybe his cam gears were off a tooth or something !! ( timing issue)

tps is so easy to check - great idea mike.

farms, if u aren’t sure how call me, ill help over phone.

24

ill be calling you later ^^

25

Check TPS. Should be at .45v closed. About 4v fully open.

I had an issue like that once, it was bad coil pack wiring. Check coil pack grounds while you are at it.

It seems to be only underload.

What does your wideband tell you?

26

**update **

so i messed around with the car today
i checked the tps sensor closed is .23v and wot is 4.34v, i did a sweep and there is no holes in the sweep to wot ( this test was done when the car was acting up )

I also noticed the car idle fp is 45psi, wand when the car is acting up under throttle the fp goes almost to 0psi, i went to the fuel pump and wired a constant 12v to the pump this symtom still presists, i looks to me like the injectors are dumping fuel into the motor causing to bog to occur at 5k ,

also another new thing i have noticed , the rev limit is going down as low as 3500prm at times

once the car is turned off and let to sit for 30 sec and started back up, i have the stock rev limiter back, but as soon as the car moves , the 5k limiter comes back

farmer

27

Try pming the people on zilvia that had the same problem, maybe they figured it out. Ive done that a couple times and it worked out in the end.

28

problem solved

farmer

29

what was the cause??

30

Another ziliva style thread?

What was it?

31

Bad fuel pump.

32

thats the first thing i told him to check weeks ago !

glad its fixed finally !

33

when i check the first time , it was operating normally, but the issue was very apparent a few days later , running a 300zx pump now and the car is running bullits

farmer

34

good stufffffff