Jump to content
SAU Community

Recommended Posts

As usuall i get a problem that is sometimes there and sometimes not.

Sometimes the rpm will rise and fall as normal.

Other times when you turn the key to on (with the engine off) the rpm will jump to 500rmp and stay there. Then when you start the car it will just sit around 3000 or 4000rpm and not move, Even at idle. Then it may very slowly move between 4000 and 3000rpm, then even down to 2000rpm. And then it may just start working as normal.....

Now i have connected my laptop to the ecu while the problem is happening and the rpm is perfectly fine.

HELP PLEASE

Link to comment
https://www.sau.com.au/forums/topic/256469-rpm-stuck-on-tacho/
Share on other sites

As usuall i get a problem that is sometimes there and sometimes not.

Sometimes the rpm will rise and fall as normal.

Other times when you turn the key to on (with the engine off) the rpm will jump to 500rmp and stay there. Then when you start the car it will just sit around 3000 or 4000rpm and not move, Even at idle. Then it may very slowly move between 4000 and 3000rpm, then even down to 2000rpm. And then it may just start working as normal.....

Now i have connected my laptop to the ecu while the problem is happening and the rpm is perfectly fine.

HELP PLEASE

Hi there, if the rpm signal is clean from the source or somewhere downstream of the source as displayed on your laptop then perhaps the next area to check is wiring loom after that.

No doubt you have checked all connections, made sure they are clean (as in not corroded). Weird intermittent faults can be due to corrupted primary signal/power/earth paths for the circuit, whatever the item or system is, particularly if it has evolved rather than "happened" after some other work has been carried out. Next thing to check (if it was me) would be for dry joints on combination meter circuit board.

My 2c

Good hunting, GW

The only things that happened before this started was i got the car tuned and the CAS was swapped with another one to try and trouble shoot a problem we were having, Swapping the CAS didn't fix the problem we were having but the other one was left on the car. A few days later i started noticing this problem

Swap a dash cluster with someone, see if it's the problem.

You said;

"Swapping the CAS didn't fix the problem we were having but the other one was left on the car. A few days later i started noticing this problem"

Still got original CAS? Worth a shot I reckon although I have no idea were the source tacho signal comes from, never had to dig it up............yet.

Cheers GW

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

    • Pressure when IDLING, is meant to be 51PSi... So that amperage value needs to go up a fair chunk... I'd personally be factoring for more like 12amp at least on those runs, and at that point you need to hope the already there wiring doesn't drop you a volt or two, as that's a lot of fuel pressure flow drop off from 13.5 to 12V! Taking idle pressure of 51psi, means the pump will be drawing a MINIMUM of 9amps all the time based on your reading of the graph (3bar base, then allowing an extra 0.5bar for boost = roughly 51psi)
    • Hi all,  I am in the market for an R200 longnose diff out of a Z31 300ZX, or S12 RSX, DR30 skyline, or similar, in a 3.9 ratio.  Preferably a late model one with the M12 crownwheel bolts.  The only easy to find advert for one of these was my ad back in 2007 when I sold it on this forum.  I sold the diff as I had sold the car it goes to, but as it turns out, after 18 years I got the car back late last year, so now I'm looking for the diff !  If anyone knows where to find a longnose R200 LSD with the M12 crownwheel bolts, drop me a line at [email protected] - Bonus paid if soomeone comes up with the original diff (stranger things have happened !).  Cheers   Ben D    
    • Hi everyone, I used to post here a bit from 2004-2013, when I owned various Nissans, in particular my S12 RSX gazelle, which was sold in 2007.  As luck would have it, after an 18 year hiatus, the car found its way back to me last year, and over the past 11 months I have had the pleasure of restoring it with my kids.  One thing that I am after in particular is a 3.9 ratio R200 LSD for it.  I actually sold the one out of the car here back in 2007 , and it would be incredible if I could track down who I sold it to, so I can see how they have progressed over the years (and to be honest, to see whether I can get the diff back !).  Anyways, hi all and let me know "where are the R200 Longnose diffs all at these days ?  Cheers Ben D  
    • Arms will be the same as the G35 or 350Z, but as above, there was a change in the lower control arm where it connects to the ball joint.  That said, you can remove the ball joint cone from your old ball joints and fit them to the new ball joints.  To be honest, I didn't think the ball joints themselves were different. The main ball joint is a bit awkward to replace, you really need to remove the steering knuckle to press out the old one.  Some people have used tools to remove it in place, but it just seemed too hard to get to. If you are going to press out/in that ball joint, then you may as well just replace the bushings in the LCA and the compression rod.  You can buy the compression rod bushing from Nissan, but the LCA bushes, you will need to go aftermarket. Much cheaper than buying the whole arm.
    • Ha, well, it's been.... a bit of a journey. Things have taken much longer than I'd hoped. I'll probably put up a thread at some stage. Hopefully soon. The car's not done any kms since my update in June though, put it that way.
×
×
  • Create New...