hey all have you ever had one of those days where the Z is running just fine and then it decided "hey i think ill stuff up today, havnt done that in a long time" well i just had one of those days... i know what the issue is but dont know how/why it happend nor how to fix it i dont know the technical terms so bare with me.....on the throttle body you know the small metal part the throttle cable connects to which in turn pulles to open the butterflies??? well that small metal part is whats causing my high idle i think for some reason...see when i just turn on the car it idles fine but as soon as i rev the engine that matal part dosnt go back to its original position, it stays "pulled" by about 5mm hence the high idle...i push it back down with my finger and it goes back to normal...this just started last night i thought it was the cable tention so i adjusted that a bit, alas no joy!! dose anyone have any ideas how to fix this?? cheerZ lads :biggrin: edit: i wouldnt consider this a major issue but when your sitting in traffic with 1100 rpm at idle shes gonna drink fuel like its her favourite beer!!
Sounds like you may have a frayed accelerater cable causing it to stick inside the outer cable. Cheers Grahame
Artin,have you checked the cond of the throttle springs,they may have stretched another thing is have you cleaned inside the throttle bodies,if they are gunked up this may be causing them not to fully close or to stick http://tech.aus300zx.com/throttle/throttle.htm
Yep clean the inside off the throttle bodies, behind the butterflies also, as best you can. To do this job properly, its best to remove them.
not recently, no i havnt checked them...when i get home today ill give it a good clean and see if the problem persists in responce to zedsr4me reply: they actually did stick for a few seconds when i accelerated hard, although this was a long time ago, still could be one reason as well
Not uncommon for the T/B actuators to Bind on the intake cam cover breathers. It sounds like something like this on yours. As you said you can manually reurn it to a proper idle. You have to find whats binding. Could be a multitude of things from pedal/cable/ cruise control/breathers/springs/TB's.
yeah... i started having one of those days every day for a while then i pulled the engine out that was a bit over 6 months ago... it's still not back in *sigh* good luck
my idle is also rather intermittent after doing a plenum pull. I'm just wondering if a dodgy TPS could cause the idle to get stuck anywhere between 1000-2000 RPM? I give the throttle a big blip it'll go back down to around 1.1k - 1.4k (still high). also doing that sitting in traffic tends to give out the wrong message unless of course you're simon (hot300) :biggrin:
Did you just throw the tps on without adjusting it properly? If so then that can definately mess with your idle. The other obvious thing is vacuum leaks...
yeah thats the 1st thing i checked when i got home last night mike: TPS need to be at 0.44 mine was at 0.38...but then again nost of my electrical cabling is all shit n cracked in most places...this could be another reason....i prolly need a full harness lol
the TPS voltage is spot on @ 0.44 when idle but could that vary when driven around if the TPS is playing up causing idle to change? checked for vacuum leaks & cleaned the TBs already.
Another possible cause for your problem I have experienced something similar, the throttle rod mechanical jam. Check on the linkages on the rod for interference with a black breather tube at the very top front edge both sides of the engine. This can cause intermittent jamming of the throttle, dont ignore it. Your next experience could be wide full open throttle jam. Very nasty. My guess is it occurs because of blow-by of pressure past the pistons and valves into the upper head. The hoses are there to relieve such pressure but I think get pushed out when the blow by is excessive. I tapped them back in with a rubber hammer then two large cable ties to keep them in place. Rough but quick fix.
crisis over lads...idle back to normal :biggrin: i gave the throttle bodies a good clean over the weekend and it was actually pretty dirty, guess thats why it wasnt closing fully the springs are ok as well as far as i can tell they havnt stretched or anything, not a big issue, ill show my mechanic just to make sure though
yeh any idea why that happens?? mine dose that as well sometimes, dont know why ...then i have a heart attack thinking something is wrong!!! lol
i have a similar problem.. after i give it a good down shift the idle will change from normal 800-900 to 1500 and will stay there constaly.. i measured the tps voltage on datascan it chages from 0.45 normal to 0.56 when the idle changes .. crazy lol.. i dont think its the tps cause the voltage would fluctuate which would show an erratic idle not a fixed position.. Will try to hunt it down soon Cheers James
High Idle. Have a look at the online service manual with particular attention to EF & EC-64. Diagnostic Procedure 1 - High Idling after Warm-up.
yeh im gonna try and figure this out as well keep us updated hmm u think it might be a gear box issue....maybe it dosnt shift down properly, and gets stuck....im just guessing though
