Jump to content
SAU Community

M35 With Issues

stagea-and-skylines
 Share

Recommended Posts

stagea-and-skylines Apprentice

stagea-and-skylines

Posted
Posted

Hi all first time poster,

i have a 2002 m35 stagea car broke down the other night and when called the raa they said fuel issues most prob fuel pump took to mechanic who ran some tests and thought same prob so swapped the fuel pump but car still doing the exact same thing will idle fine but for some reason when you give it throttle is does nothing besides try and die the mechanic said for some reason the pump is only getting 1/4 of the voltage it should be and the injectors are dumping three times as much fuel as they should be, he has no idea why has been troubleshooting for a week now, any one else with this issue and how they fixed it ?

Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/
Share on other sites
conan7772 Mentor

conan7772

Posted
Posted

How did he establish fuel pump? Did he put a pressure gauge on it?

Also, 3 times the fuel is a weird statement, and unmeasurable. Time to take it somewhere who knows what they are doing.

+1, take it to someone who knows the car..

Both my mechanics have never seen a VQ25DET before.. and it's 14 years old

Don't rush into process of elimination.

Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/#findComment-7604940
Share on other sites
BoostdR Mentor

BoostdR

Posted
Posted (edited)

Fuel pump runs lower voltage at idle to reduce noise and heat.

Symptoms sound like the Air Flow Meter could be stuffed. Unplug it and restart your car a couple of time so the ecu knows its unplugged and will enter limp home mode(won't allow revs much over 2,000rpm which is normal). If it then idles smoother the AFM sensor may need replacing. I replaced mine with a genuine Nissan item after my Chinese sensor lasted 4 days but others say the Chinese copies are more reliable. Maybe talk to scotty about which one he has had good reliability with. I'm sure he will chime in soon.

*a loose intercooler pipe or charge system leak will also give the similar symptoms as a blown AFM. So check them before buying a new sensor if limp home mode works.

Matt

Edited by BoostdR
  • Like 1
Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/#findComment-7604976
Share on other sites
scotty nm35 Grand Master

scotty nm35

Posted
Posted

It's ferked, and the ecu has no way of telling it's ferked.

Scanners don't tell you the fault, they only tell you what the ECU thinks the fault might be, perhaps.

Edit, does it run the same if you unplug the AFM?

Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/#findComment-7605202
Share on other sites
scotty nm35 Grand Master

scotty nm35

Posted
Posted

Does it drive the same in AFM limp mode?

If it idles fine, then it obviously isn't the fuel pump, slap a known good AFM element in there and try it out, it's the only way to rule the AFM from the equation. The AFM's rarely fail where the ECU actually throws a code in my experience, and I have changed literally hundreds of them.

Once it's sorted, get a new mechanic. I suspect he just wasted your time and money changing a perfectly good pump. Do you know what pump he put in there? it might need to be re-wired if it's an aftermarket Walbro or similar. They don't like that low voltage at idle/cruise (that all cars do these days.)

Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/#findComment-7605210
Share on other sites
stagea-and-skylines Apprentice

stagea-and-skylines

Posted
  • Author
Posted

The pump he put in was a walbro pump yes, the mechanic has only ever dealt with upgrading parts on m35 stageas before so it all one big learning process unfortunately he never had one with this problem before like most mechanics I've spoken to before him

Link to comment
https://www.sau.com.au/forums/topic/459758-m35-with-issues/#findComment-7605223
Share on other sites

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      NC MX5

      By MBS206 · Posted

      My guesstimate, with no real numbers to back it up, is it won't effect it greatly at all.its not a huge change in position, and I can't see the air flow changing from in turbulence that much based on distance, and what's in front of it. Johnny and Brad may have some more numbers to share from experience though.
    • dbm7
      Automatic Power Button Light Flashing

      By dbm7 · Posted

      Which solenoid? Why was it changed? Again, why was this done? ...well, these wear..but ultimately, why was it changed? Did you reset the idle voltage level after fitment? I'm just a tad confused ~ the flash code doesn't allude to these items being faulty, so in my mind the only reason to change these things, would be some drive-ability issue....and if that's the case, what was the problem? Those questions aside, check if the dropping resistor is OK ...should be 11~14 ohms (TCU doesn't throw a flash code for this) ~ also, these TCU designs have full time power (to keep fault code RAM alive), and I think that'll throw a logic code (as opposed to the 10 hardware codes), if that power is missing (or the ram has gone bad in the TCU, which you can check..but that's another story here perhaps).
    • The Bogan
      NC MX5

      By The Bogan · Posted

      Question for people who "know stuff" I am looking at doing the new intake like the one in the picture (the pictured is designed for the OEM TB and intake plenum), this design has the filter behind the front bar, but, the filter sits where the OEM duct heads into the front bar, and the standard aperture when the OEM ducting is removed allows the filter to pulled back out of the front bar into the engine bay for servicing, a simple blanking plate is used to seal the aperture behind the filter This will require a 45° silicone hose from the TB, like the alloy pipe that is currently there, to another 45° silicone hose to get a straight run to the aperture in the front bar Question: how will it effect the tune if I move the MAF about 100-150mm forward, the red is around where my MAF is currently, and the green would be where it would end up Like this This is the hole the filter goes through  Ends up like this LOL..Cheers    
    • Duncan
      R34 Plug Identification

      By Duncan · Posted

      Despite the level up question, actually I do know what that is....it is a pressure sender wire.  So check out around the oil filter for an oil pressure sender, or maybe fuel pressure near the filter or on the engine. Possibly but less likely coolant pressure sensor because they tend to be combined temp/pressure senders if you have one. Could also be brake pressure (in a brake line somewhere pre ABS) but maybe I'm the only one that has that on a skyline.
    • joshuaho96
      Automatic Power Button Light Flashing

      By joshuaho96 · Posted

      Pull codes via the self-diagnosis procedure. As far as I can tell this is just a sign of transmission issues but not a code unto itself.
×
×
  • Create New...