Jump to content
SAU Community

Recommended Posts

Yesterday, whilst driving my car and stopping at the lights, ocasioanlly the car would get into a sort of "rev Spasm".... It would drop revs almost to zero on the verge of stalling, then bounce back up to 1200rpm, and this would cycle over and over until I iether switched if the engine and started up again, or nursed the Idle( very hard to get idle back to normal by accelarating)

My AFM hasnt ever been playing up, however i am going to clean this tomorrow...

Is there anything else which can cause this? will the AAC Valve, be having an effect?

I also noticed on my boost gauge as it was trying to recover idle, the vacuum pressure would should up all the way up to zero, perhaps a little under. Which seems extremely wierd to me? does this signify a vacuum leak allong the lines somewhere??

Any help apreciated

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/
Share on other sites

before i got my car tuned my car did this, way to stop it havin a spazz, was to rev it so you got boost and vent the bov, and then it stoped serging, but it was really gay because at a set of lights you look like a tool reving ya car ahahah spechly if theres some shit hot car next to ya.... but thats how i solved my serge before i got the safc and tune so yeah....

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1729646
Share on other sites

I had the exact same problem yesterday, but it went away once I turned the air conditioner off.

It was really strange as the car drove fine with the air con on for about 5 mins, then it started to idle really rough and drove like a dog. Once I turned the air con off and gave the car a few small revs, it seemed to rectify the problem and the car drove fine again. I thought perhaps it was a bit of bad fuel or something, but when I drove the car later in the day with the air con on again, it did the same thing again.

Car's going back to the workshop this week for a few other things, so I'll be getting my mechanic to have a look at it for me while it's there.

Anyone got any idea what may be causing this?

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1729662
Share on other sites

Cleaning your MAF meter should help. If switching the car off and then on again fixes the problem I would point towards a faulty MAF meter. Try other things like cleaning the throttle body and AAC valve at the same time and see if these help.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1730646
Share on other sites

Mine started doing this revving thing when i got my power fc installed

drives perfectly, but at idle just does this stupid down to 500 then to 1100 and yeah keeps going

it does look pretty stupid when ppl look at ya and they think you doing it. i just want to put the window down and say its the car ,

im takin it back to fist at wacol and they are going to have a look at it

let yas know what it is, if they do fix it.

Also on wednesday i turned my car off and when i went to turn it back on again, it just made a click sound and didnt start i had to wait abit till it would start again, a bit weird, but hopefully that will be sorted out too

and i went down the quarter last wednesday and the check warning light for the engine came on when the car is under load.

I'll post back on wednesday

THanks

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1730772
Share on other sites

Sorta. An AFM is an Air Flow Meter and measures Air Flow via air flap and needle.

A MAF meter is a Mass Air Flow Meter and measure Air Mass via hotwire.

They both virtually do the same thing and essentially achieve the same results but through different methods.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1730960
Share on other sites

Yeah i have my car do that idle thing too.

Ive noticed its always on a hot and muggy day that when i start the car its idle rate will go up and down and some times even stall . But it seems to iron it self out after it gets running for a bit.

I will have to check my MAF. Good to hear that my car isn't the only one :D

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1736351
Share on other sites

i went to fist

had the hand controller hooked up on the car

idle was put up to 900 instead of 850

some base setting was low and , didnt catch the other thing he said

but it was high, so he made it so it equalled out .

i drove it tonight , seems to go pretty good , havent noticed the idle go whacko yet but let yas know .

I'll try and find out what the things on the hand controller exactly were

i think i might have to get one,

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1736465
Share on other sites

Hi Guys,

I had the problem a few months ago, not s much at idle but always before turbo's kicked in, it would cut out and gve a sharp jerk, its been fixed, the problem was that there was excess oil inthe airflow metres, got cleaned out, and works fine, but if the problem continues its time to replace air flow meters.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1748766
Share on other sites

  • 2 weeks later...

Check your thottle position sensor. Tap it with a soft mallet while its running to check it's connections and internals are ok. Mine was fine when adjusted, but acted up after 5 minutes driving and drove all jerky and misfired and crap.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1770880
Share on other sites

Another thing you could try is check your alternator is putting out the correct voltage. Make sure you check it at the terminal on the back of the alt...not just at the battery. If your output voltage is low eg...11.80V, the battery light will still not come on but the fuel pump and ignition may not have enough to run them properly as the computer will only see about 9.5-10V of that.

Your problem is probably elsewhere but it doesn't hurt to check as it will cause idle probs.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1772701
Share on other sites

any way it could be an Idle port prolem on ur throttle body? it can have trouble switching from air going through the throttle body, to it switching totally to the idle port. If it gets blocked up with gunk or carbon it can make that car act a bit like that at times or eventually make the car stall. just a thought.

Link to comment
https://www.sau.com.au/forums/topic/95562-rough-idle/#findComment-1772866
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


  • Similar Content

  • Latest Posts

    • I did end up getting it sorted, as GTSBoy said, there was a corroded connection and wire that needed to be replaced. I ended up taking out the light assembly, giving everything a good clean and re-soldered the old joints, and it came out good.
    • Wow, thanks for your help guys 🙏. I really appreciate it. Thanks @Rezz, if i fail finding any new or used, full or partial set of original Stage carpets i will come back to you for sure 😉 Explenation is right there, i just missed it 🤦‍♂️. Thanks for pointing out. @soviet_merlin in the meantime, I received a reply from nengun, and i quote: "Thanks for your message and interest in Nengun. KG4900 is for the full set of floor mats, while KG4911 is only the Driver's Floor Mat. FR, RH means Front Right Hand Side. All the Full Set options are now discontinued. However, the Driver's Floor Mat options are still available according to the latest information available to us. We do not know what the differences would be, but if you only want the one mat, we can certainly see what we can find out for you". Interesting. It seems they still have some "new old stock" that Duncan mentioned 🤔. I wonder if they can provide any photos......And i also just realized that amayama have G4900 sets. I'm tempted too. 
    • Any update on this one? did you manage to get it fixed?    i'm having the same issue with my r34 and i believe its to do with the smart entry (keyless) control module but cant be sure without forking out to get a replacement  
    • So this being my first contribution to the SAU forums, I'd like to present and show how I had to solve probably one of the most annoying fixes on any car I've owned: replacing a speedometer (or "speedo") sensor on my newly acquired Series 1 Stagea 260RS Autech Version. I'm simply documenting how I went about to fix this issue, and as I understand it is relatively rare to happen to this generation of cars, it is a gigantic PITA so I hope this helps serve as reference to anyone else who may encounter this issue. NOTE: Although I say this is meant for the 260RS, because the gearbox/drivetrain is shared with the R33 GTR with the 5-speed manual, the application should be exactly the same. Background So after driving my new-to-me Stagea for about 1500km, one night while driving home the speedometer and odometer suddenly stopped working. No clunking noise, no indication something was broken, the speedometer would just stop reading anything and the odometer stopped going up. This is a huge worry for me, because my car is relatively low mileage (only 45k km when purchased) so although I plan to own the car for a long time, a mismatched odometer reading would be hugely detrimental to resale should the day come to sell the car. Thankfully this only occurred a mile or two from home so it wasn't extremely significant. Also, the OCD part of me would be extremely irked if the numbers that showed on my dash doesn't match the actual ageing of the car. Diagnosing I had been in communication with the well renown GTR shop in the USA, U.P.garage up near University Point in Washington state. After some back and forth they said it could be one of two things: 1) The speedometer sensor that goes into the transfer case is broken 2) The actual cluster has a component that went kaput. They said this is common in older Nissan gauge clusters and that would indicate a rebuild is necessary. As I tried to figure out if it was problem #1, I resolved problem #2 by sending my cluster over to Relentless Motorsports in Dallas, TX, whom is local to me and does cluster and ECU rebuilds. He is a one man operation who meticulously replaces every chip, resistor, capacitor, and electronic component on the PCB's on a wide variety of classic and modern cars. His specialty is Lexus and Toyota, but he came highly recommended by Erik of U.P.garage since he does the rebuilds for them on GTR clusters.  For those that don't know, on R32 and R33 GTR gearboxes, the speedometer sensor is mounted in the transfer case and is purely an analog mini "generator" (opposite of an alternator essentially). Based on the speed the sensor spins it generates an AC sine wave voltage up to 5V, and sends that via two wires up to the cluster which then interprets it via the speedometer dial. The signal does NOT go to the ECU first, the wiring goes to the cluster first then the ECU after (or so I'm told).  Problems/Roadblocks I first removed the part from the car on the underside of the transfer case (drain your transfer case fluid/ATF first, guess who found out that the hard way?), and noted the transfer case fluid was EXTREMELY black, most likely never changed on my car. When attempting to turn the gears it felt extremely gritty, as if something was binding the shaft from rotating properly. I got absolutely no voltage reading out of the sensor no matter how fast I turned the shaft. After having to reflow the solder on my AFM sensors based on another SAU guide here, I attempted to disassemble the silicone seal on the back of the sensor to see what happened inside the sensor; turns out, it basically disintegrated itself. Wonderful. Not only had the electrical components destroyed themselves, the magnetic portion on what I thought was on the shaft also chipped and was broken. Solution So solution: find a spare part right? Wrong. Nissan has long discontinued the proper sensor part number 32702-21U19, and it is no longer obtainable either through Nissan NSA or Nissan Japan. I was SOL without proper speed or mileage readings unless I figured out a way to replace this sensor. After tons of Googling and searching on SAU, I found that there IS however a sensor that looks almost exactly like the R33/260RS one: a sensor meant for the R33/R34 GTT and GTS-T with the 5 speed manual. The part number was 25010-21U00, and the body, plug, and shaft all looked exactly the same. The gear was different at the end, but knowing the sensor's gear is held on with a circlip, I figured I could just order the part and swap the gears. Cue me ordering a new part from JustJap down in Kirrawee, NSW, then waiting almost 3 weeks for shipping and customs clearing. The part finally arrives and what did I find? The freaking shaft lengths don't match. $&%* I discussed with Erik how to proceed, and figuring that I basically destroyed the sensor trying to get the shaft out of the damaged sensor from my car. we deemed it too dangerous to try and attempt to swap shafts to the correct length. I had to find a local CNC machinist to help me cut and notch down the shaft. After tons of frantic calling on a Friday afternoon, I managed to get hold of someone and he said he'd be able to do it over half a week. I sent him photos and had him take measurements to match not only the correct length and notch fitment, but also a groove to machine out to hold the retentive circlip. And the end result? *chef's kiss* Perfect. Since I didn't have pliers with me when I picked up the items, I tested the old gear and circlip on. Perfect fit. After that it was simply swapping out the plug bracket to the new sensor, mount it on the transfer case, refill with ATF/Nissan Matic Fluid D, then test out function. Thankfully with the rebuilt cluster and the new sensor, both the speedometer and odometer and now working properly!   And there you have it. About 5-6 weeks of headaches wrapped up in a 15 minute photo essay. As I was told it is rare for sensors of this generation to die so dramatically, but you never know what could go wrong with a 25+ year old car. I HOPE that no one else has to go through this problem like I did, so with my take on a solution I hope it helps others who may encounter this issue in the future. For the TL;DR: 1) Sensor breaks. 2) Find a replacement GTT/GTS-T sensor. 3) Find a CNC machinist to have you cut it down to proper specs. 4) Reinstall then pray to the JDM gods.   Hope this guide/story helps anyone else encountering this problem!
    • So this being my first contribution to the SAU forums, I'd like to present and show how I had to solve probably one of the most annoying fixes on any car I've owned: replacing a speedometer (or "speedo") sensor on my newly acquired Series 1 Stagea 260RS Autech Version. I'm simply documenting how I went about to fix this issue, and as I understand it is relatively rare to happen to this generation of cars, it is a gigantic PITA so I hope this helps serve as reference to anyone else who may encounter this issue. NOTE: Although I say this is meant for the 260RS, because the gearbox/drivetrain is shared with the R33 GTR with the 5-speed manual, the application should be exactly the same. Background So after driving my new-to-me Stagea for about 1500km, one night while driving home the speedometer and odometer suddenly stopped working. No clunking noise, no indication something was broken, the speedometer would just stop reading anything and the odometer stopped going up. This is a huge worry for me, because my car is relatively low mileage (only 45k km when purchased) so although I plan to own the car for a long time, a mismatched odometer reading would be hugely detrimental to resale should the day come to sell the car. Thankfully this only occurred a mile or two from home so it wasn't extremely significant. Also, the OCD part of me would be extremely irked if the numbers that showed on my dash doesn't match the actual ageing of the car. Diagnosing I had been in communication with the well renown GTR shop in the USA, U.P.garage up near University Point in Washington state. After some back and forth they said it could be one of two things: 1) The speedometer sensor that goes into the transfer case is broken 2) The actual cluster has a component that went kaput. They said this is common in older Nissan gauge clusters and that would indicate a rebuild is necessary. As I tried to figure out if it was problem #1, I resolved problem #2 by sending my cluster over to Relentless Motorsports in Dallas, TX, whom is local to me and does cluster and ECU rebuilds. He is a one man operation who meticulously replaces every chip, resistor, capacitor, and electronic component on the PCB's on a wide variety of classic and modern cars. His specialty is Lexus and Toyota, but he came highly recommended by Erik of U.P.garage since he does the rebuilds for them on GTR clusters.  For those that don't know, on R32 and R33 GTR gearboxes, the speedometer sensor is mounted in the transfer case and is purely an analog mini "generator" (opposite of an alternator essentially). Based on the speed the sensor spins it generates an AC sine wave voltage up to 5V, and sends that via two wires up to the cluster which then interprets it via the speedometer dial. The signal does NOT go to the ECU first, the wiring goes to the cluster first then the ECU after (or so I'm told).  Problems/Roadblocks I first removed the part from the car on the underside of the transfer case (drain your transfer case fluid/ATF first, guess who found out that the hard way?), and noted the transfer case fluid was EXTREMELY black, most likely never changed on my car. When attempting to turn the gears it felt extremely gritty, as if shttps://imgur.com/6TQCG3xomething was binding the shaft from rotating properly. After having to reflow the solder on my AFM sensors based on another SAU guide here, I attempted to disassemble the silicone seal on the back of the sensor to see what happened inside the sensor; turns out, it basically disintegrated itself. Wonderful. Not only had the electrical components destroyed themselves, the magnetic portion on what I thought was on the shaft also chipped and was broken. Solution So solution: find a spare part right? Wrong. Nissan has long discontinued the proper sensor part number 32702-21U19, and it is no longer obtainable either through Nissan NSA or Nissan Japan. I was SOL without proper speed or mileage readings unless I figured out a way to replace this sensor. After tons of Googling and searching on SAU, I found that there IS however a sensor that looks almost exactly like the R33/260RS one: a sensor meant for the R33/R34 GTT and GTS-T with the 5 speed manual. The part number was 25010-21U00, and the body, plug, and shaft all looked exactly the same. The gear was different at the end, but knowing the sensor's gear is held on with a circlip, I figured I could just order the part and swap the gears. Cue me ordering a new part from JustJap down in Kirrawee, NSW, then waiting almost 3 weeks for shipping and customs clearing. The part finally arrives and what did I find? The freaking shaft lengths don't match. $&%* I discussed with Erik how to proceed, and figuring that I basically destroyed the sensor trying to get the shaft out of the damaged sensor from my car. we deemed it too dangerous to try and attempt to swap shafts to the correct length. I had to find a local CNC machinist to help me cut and notch down the shaft. After tons of frantic calling on a Friday afternoon, I managed to get hold of someone and he said he'd be able to do it over half a week. I sent him photos and had him take measurements to match not only the correct length and notch fitment, but also a groove to machine out to hold the retentive circlip. And the end result? *chef's kiss* Perfect. Since I didn't have pliers with me when I picked up the items, I tested the old gear and circlip on. Perfect fit. After that it was simply swapping out the plug bracket to the new sensor, mount it on the transfer case, refill with ATF/Nissan Matic Fluid D, then test out function. Thankfully with the rebuilt cluster and the new sensor, both the speedometer and odometer and now working properly!   And there you have it. About 5-6 weeks of headaches wrapped up in a 15 minute photo essay. As I was told it is rare for sensors of this generation to die so dramatically, but you never know what could go wrong with a 25+ year old car. I HOPE that no one else has to go through this problem like I did, so with my take on a solution I hope it helps others who may encounter this issue in the future. For the TL;DR: 1) Sensor breaks. 2) Find a replacement GTT/GTS-T sensor. 3) Find a CNC machinist to have you cut it down to proper specs. 4) Reinstall then pray to the JDM gods.   Hope this guide/story helps anyone else encountering this problem!
×
×
  • Create New...