Jump to content
SAU Community

Recommended Posts

SKYLINE WON'T drive normally

So after thrashing it down the road, my car went into a LIMP mode, now when I drive, it won't go over 2000rpm, even when parked I can't rev it pass 2000, it's like hitting a rev Limiter. So I suspected the AFM, spark plugs and Coils so, I cleaned the AFM (sprayed it down) and replace all my coils and spark plugs. Car starts up great but the problem is still there, what could it be? 

I have reset my ECU already.

Before the limp mode starts, the car will drive fine till about down 3mins after it will just LIMP MODE the whole way, once I start my car again it will be normal for abit and then again LIMP

My Skyline is R34 Triptronic.

My engine light has always been on before this occur so I can't tell if another problem popped up so I have to check on that. 

I think also my A/T flashes before I start my car

IMG_2500.MOV

Link to comment
https://www.sau.com.au/forums/topic/467992-skyline-wont-drive-normally/
Share on other sites

  On 03/12/2016 at 9:40 AM, ADDSKI said:
If your Mass Airflow sensor is broken the car won't exceed 2000rpm

This thing is when I start the car it will drive normal and goes over 2000rpm but after about 3 mins or so it will just start to choke and chug and can't even drive over 40kms :(
  On 02/12/2016 at 8:58 AM, Jonic said:

My engine light has always been on before this occur so I can't tell if another problem popped up so I have to check on that. 

Expand  

It was on for a reason - there's something wrong. **Sigh**

So God only knows what might have broken to cause your current situation. (but I'll back the AFM as the chief culprit)

  • Like 1
  • 4 weeks later...

Car runs fine now and I didn't do anything really, just reset the code and I can finally drive it pass 2000rpm. Problem now is when I'm driving, at a red light my idle drops and sometimes the car dies, but starts right back up no problem. Any clues because my mechanics are clueless. The cel code was A/T and ABS fault but that has nothing to do with my current problem zz

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Ha! well, there's your problem!  Guess the last person in there didn't have great attention to detail....
    • It seems like you guys want to behave like rabid dogs, rather than gentlemen... Knowing one has jumped in on a fellow comrades near done deal, and sniped it at the last second, how can one sleep at night?
    • My wifes says we have a spare set.
    • Good news!!! Changed the O ring today and I’ve got the “pssshhhh” back when I open the fuel cap 😂🙌🏼🙌🏼 It was 100% the O ring because that bloody thing was inside the fuel tank 😂😂😂😂😂 Fitting new fuel pump was a pain as always since the DW is a bit longer than stock. But she’s running!!! ❤️
    • PWM quite literally just chops the ful 12V voltage on and off at whatever duty cycle you're running it at. If you're running it 100%, then it is on full voltage all the time, same as if there was no PWM. If you run it at 50% duty cycle, it is only seeing the full 12V half of the time. This is broadly equivalent to running it at 6V. But the crucial difference is that motors (and a lot of other loads) don't like being powered at low volts. They will either fail to start rotating, or draw a shit ton of current, or other undesirable things. But if you give them the full volt, and then a short period of no volts, and then some more full volts, then the times when they are seeing power they are seeing all the voltage, and they are happy. But you get the performance out of them as if they were only seeing that fraction of the full voltage. It is not really easy to answer your question about what flow you will get out of it at 50% duty cycle. I can tell you that it is not as simple as you think. For a start, that 460 L/h pump is not going to flow 460 when you're on boost. When you're on boost you will be somewhere down the sloping part of that red line. If you have 15 psi of boost, then the pump can only deliver about 95 gal/h, which is <380L/h. So your simple 50% on 460 = 230 wasn't going to work anyway. But also, it won't deliver 50% of 380 either, because when you devolt or PWM trim th epower being fed to the pump, it is not able to deliver flow or pressure in the same way. 50% duty cycle will probably produce <50% of the full voltage flow. The way to find out what duty cycle you need to run it at at low load (ie, at idle) is to idle it and turn the DC down until you start to lose fuel pressure, then turn it back up above that with some extra for safety. And then you do the same thing at full load, in case it doesn't need anywhere near 100% DC. And if you're careful/caution/prudent, you will also do it at a couple of loads in between so you can shape the DC map against load. It might not be linear between the two end points.
×
×
  • Create New...