Jump to content
SAU Community

Limp Mode

Barras

By Barras,
in Four Door Family & Wagoneers

 Share

Recommended Posts

bigkevracer Grand Master

bigkevracer

Posted
Posted

I seem to be having the same problem, except more intermittent.

Car threw a code on the dyno for TPS, without completely killing the throttle.

I didn't have great throttle response afterwards, but the throttle _always_ worked.

We cleared the code, throttle response was better.

Now twice in the last few days it has suddenly lost all throttle response, just idles. This wasn't on WOT or taking off, just normal street/highway driving. I pull up ASAP, turn the car off, turn it immediately back on, and throttle is fine.

No code clearing, no mucking about: Goes bad, turn off, turn back on, goes good.

I think it could be one of four things:

  1. TPS sensor - most sensible thing given that's the code it threw
  2. Cruise control, which has a T piece in the throttle - both times it's happened so far I've had the cruise control on and I've either been using cruise or just turned it off
  3. F-con throttle map
  4. Throttle wire on the ECU, where I had to splice in the wiring for the EVC

None make sense to me given the weird behaviour. I'm thinking of disconnecting the throttle T-piece for the cruise and seeing how it goes. If it continues, replace the TPS sensor.

Anyone else noticed anything similar?

scotty nm35 Grand Master

scotty nm35

Posted
Posted

I had to disconnect a cruise the other day for the same fault, I have also seen the throttle assembly being the issue. (tps)

Mine did the same thing with the pivot throttle controller plugged in, any resistance difference between the two throttle signals will trigger limp mode.

Try disconnecting the cruise for a while, it may well be the answer.

Daleo Grand Master

Daleo

Posted
Posted

I seem to be having the same problem, except more intermittent.

Car threw a code on the dyno for TPS, without completely killing the throttle.

I didn't have great throttle response afterwards, but the throttle _always_ worked.

We cleared the code, throttle response was better.

Now twice in the last few days it has suddenly lost all throttle response, just idles. This wasn't on WOT or taking off, just normal street/highway driving. I pull up ASAP, turn the car off, turn it immediately back on, and throttle is fine.

No code clearing, no mucking about: Goes bad, turn off, turn back on, goes good.

I think it could be one of four things:

  1. TPS sensor - most sensible thing given that's the code it threw
  2. Cruise control, which has a T piece in the throttle - both times it's happened so far I've had the cruise control on and I've either been using cruise or just turned it off
  3. F-con throttle map
  4. Throttle wire on the ECU, where I had to splice in the wiring for the EVC

None make sense to me given the weird behaviour. I'm thinking of disconnecting the throttle T-piece for the cruise and seeing how it goes. If it continues, replace the TPS sensor.

Anyone else noticed anything similar?

I have just had this happen on mine too, throttle hasn't failed, but response is really lazy below 3000 rpm, with basically no boost.

I actually thought it might've been a camshaft position sensor.

Reset once, was fine for a couple of days, then lazy again. Reset, but noted the code, which was 1705; throttle body.

I'm running cruise control also, but I have been for well over a year now with no issue. I don't think that's the issue.

Going to have a poke around tomorrow, check plug & pins are clean & plugged in; but I would think the next step is a spare known tb to see whether it returns.

I'd be interested to hear what you come up with Ryan.

bigkevracer Grand Master

bigkevracer

Posted
Posted

Cheers guys.

I'm with you Dale, don't think it is cruise control. Doesn't make sense after a year of fault free running.

On the other hand it is the easiest thing to test, and of Scotty thinks it could be a signal problem I'll give it a try.

Just weird the problem didn't appear until the fcon went in...

Daleo Grand Master

Daleo

Posted
Posted

After another look at the fault code listing, mine is actually; P1705 Throttle Position Sensor Circuit A/T

This could also explain why mine didn't want to kick down, or unlock the converter with a small throttle input.

I might be looking elsewhere...

bigkevracer Grand Master

bigkevracer

Posted
Posted

After another look at the fault code listing, mine is actually; P1705 Throttle Position Sensor Circuit A/T

This could also explain why mine didn't want to kick down, or unlock the converter with a small throttle input.

I might be looking elsewhere...

Easiest thing is to replace the sensor though, or that's what my thought was...

Commsman Veteran

Commsman

Posted
Posted

You've had some stuff going on with your car lately, hey Ryan.

I also don't think it's the cruise as mine hasn't given me that problem either (although I don't drive it much ;) ), but like you say - it's easy to rule out as it only takes a minute to unplug the throttle harness.

If the fault appears semi-regularly now, it shouldn't be long before you know. Hopefully it's not the F-Con but a TPS as that's means the F-Con is OK (as the last 'electrical' mod you've done it has to be high on the list of possibilities). It could also be the cruise control interacting badly with the F-Con, but I don't know anything about how they wire in so just throwing it out there...

The timing of the fault is a bit of a coincidence with the F-Con going in though, & I have a hard time believing coincidences, so good luck with the fault finding.

bigkevracer Grand Master

bigkevracer

Posted
Posted

I have Leon, although most are my own doing so can't entirely blame Mr Nissan.

I find it hard to believe it would be the F-con, but like you said it is one of the last electrical mods. Scotty has been running the F-con with the cruise for a while now without issue, and I also find it hard to believe it'd be the mapping for the throttle in the F-con if the throttle completely dies.

They wire in by plugging in between the ECU plug and the ECU, entirely piggy back, except for a MAP and IAT sensor harness in my case.

Daleo Grand Master

Daleo

Posted
Posted

dale, I have a spare TB and pedal sensor if you want to try them on your car for a few weeks

Thanks Iain! I'm going to see if it comes back this week, and I'll be in touch.

I still have to get the name of the shade sail place for you too.

Cheers, Dale.

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

    • kevboost7
      Magnetic Drain Plug Snapped in Half

      By kevboost7 · Posted

      Update: I got the magnet out. I bought 3 different flexible magnetic reach tools, but none of them worked. The magnet on the tip was all less than 2lbs of force, so i had to buy a special cylindrical magnet that had a pull force of 9lbs.  The magnet finally came in the mail yesterday, so i got under the car to get to work. The super strong magnet isn't that long, so i only have about 1 finger pinch lengths to hold it. I was so scared when i was going in the hole, that the 9lb magnet would just fly away inside the oil pan never to be seen again, but i had my butt cheeks clenched and finger gripped on that thing so tight, i managed to get it to suck the other magnet out.  It was a victory for me last night.         
    • MBS206
      New fix for low tyre pressure from bmw

      By MBS206 · Posted

      Yep, pretty much what you said is a good summary. The aftermarket thing just attached to the rim, then has two lines out to valve stems, one to inner wheel, one to outer wheel. Some of the systems even start to air up as you head towards highway speed. IE, you're in the logging tracks, then as speeds increase it knows you're on tarmac and airs up so the driver doesn't even have to remember. I bet the ones that need driver intervention to air up end up seeing a lot more tyre wear from "forest pressures" in use on the highway!
    • sunsetR33
      Anyone know this frontpipe?

      By sunsetR33 · Posted

      Yes, but you need to do these type certifications for tuning parts. That is the absurd part here. Meaning tuning parts are very costly (generally speaking) as well as the technical test documentation for say a turbo swap with more power. It just makes modifying everything crazy expensive and complicated. That bracket has been lost in translation many years ago I assume, it was not there.
    • dbm7
      New fix for low tyre pressure from bmw

      By dbm7 · Posted

      Hahaha, yeah.... not what you'd call a tamper-proof design.... but yes, with the truck setup, the lines are always connected, but typically they sit just inside the plane of the rear metal mudguards, so if you clear the guards you clear the lines as well. Not rogue 4WD tracks with tree branches and bushes everywhere, ready to hook-up an air hose. You can do it externally like a mod, but dedicated setups air-pressurize the undriven hubs, and on driven axles you can do the same thing, or pressurize the axles (lots of designs out there for this idea)... https://www.trtaustralia.com.au/traction-air-cti-system/  for example.... ..the trouble I've got here... wrt the bimmer ad... is the last bit...they don't want to show it spinning, do they.... give all the illusion that things are moving...but no...and what the hell tyre profile is that?...25??? ...far kernel, rims would be dead inside 10klms on most roads around here.... 😃
    • joshuaho96
      Anyone know this frontpipe?

      By joshuaho96 · Posted

      You're just describing how type certification works. Personally I would be shocked to discover that catalytic converter is not in the stock mounting position. Is there a bracket on the transfer case holding the catalytic converter and front pipe together? If so, it should be in stock position. 
×
×
  • Create New...