tony tt Posted April 11, 2012 Author Share Posted April 11, 2012 I had a similar issue on my previous auto TT, it was sometimes idling low, mainly when it was warm. Turned out the throttle cable was a little loose (I mean ever so slightly). Just a thought Tony. Abz i never even thought of that if its as simple as that ill be over the moon cheers. Quote Link to comment Share on other sites More sharing options...
Abz Posted April 11, 2012 Share Posted April 11, 2012 Abz i never even thought of that if its as simple as that ill be over the moon cheers. Mine was, my mechanic nearly slapped me for not checking it myself! Quote Link to comment Share on other sites More sharing options...
tony tt Posted April 11, 2012 Author Share Posted April 11, 2012 Mine was, my mechanic nearly slapped me for not checking it myself! If it is that ill throw myself into my garage and give myself a sound kicking mate!! Quote Link to comment Share on other sites More sharing options...
Abz Posted April 11, 2012 Share Posted April 11, 2012 If it is that ill throw myself into my garage and give myself a sound kicking mate!! Can you record it please Quote Link to comment Share on other sites More sharing options...
tony tt Posted April 11, 2012 Author Share Posted April 11, 2012 Can you record it please haha ill try! Quote Link to comment Share on other sites More sharing options...
bigbloodyturbo Posted April 11, 2012 Share Posted April 11, 2012 How did the throttle cable cause your low idle? Surely if it was loose the throttle would just sit on the stop as it would in a normal situation? Quote Link to comment Share on other sites More sharing options...
Mattross1313 Posted April 11, 2012 Share Posted April 11, 2012 Thts a good point Abz. I was actually nosing around under the 'hood' yesterday evening and noticed a small amount of slack in the throttle cable. Ill check it out tomorrow Quote Link to comment Share on other sites More sharing options...
rider Posted April 11, 2012 Share Posted April 11, 2012 Are you certain the rev guage is reading the correct value as 300rpm is very low to maintain a steady tickover. Does the rpm increase by 300 when you engage the air con? It's easy to check if the guage is reading OK if you don't have access to a tachometer by running at a set speed in gear the rpm to speed will obviously depend on the gear selected and whether its an auto or manual gearbox. Quote Link to comment Share on other sites More sharing options...
Abz Posted April 11, 2012 Share Posted April 11, 2012 How did the throttle cable cause your low idle? Surely if it was loose the throttle would just sit on the stop as it would in a normal situation? I can't remember exactly as it was a couple of years ago, but because of the slack it caused the cable to return too much, can't remember if he adjusted the bump or not. Took him 5 mins. Thts a good point Abz. I was actually nosing around under the 'hood' yesterday evening and noticed a small amount of slack in the throttle cable. Ill check it out tomorrow Quote Link to comment Share on other sites More sharing options...
tony tt Posted April 11, 2012 Author Share Posted April 11, 2012 Are you certain the rev guage is reading the correct value as 300rpm is very low to maintain a steady tickover. Does the rpm increase by 300 when you engage the air con? It's easy to check if the guage is reading OK if you don't have access to a tachometer by running at a set speed in gear the rpm to speed will obviously depend on the gear selected and whether its an auto or manual gearbox. It's an auto box rev guage is reading fine. It's 300 borderline stalling. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 12, 2012 Share Posted April 12, 2012 You need to scope the feeds to the idle control valve and check they are all functional, plus you need to feed signals to the valve to check it moves correctly in response. If that all checks out you need to re calibrate the pot on the throttle body and scope ITS output. Without a scope or an original Toyota scan tool you can mess around for weeks with this sort of issue. The basics are it's either not getting enough air at idle or it has the wrong air / fuel ratio at idle. Fiddle with throttle stop screws at your peril!!!!!!! Quote Link to comment Share on other sites More sharing options...
tony tt Posted April 13, 2012 Author Share Posted April 13, 2012 You need to scope the feeds to the idle control valve and check they are all functional, plus you need to feed signals to the valve to check it moves correctly in response. If that all checks out you need to re calibrate the pot on the throttle body and scope ITS output. Without a scope or an original Toyota scan tool you can mess around for weeks with this sort of issue. The basics are it's either not getting enough air at idle or it has the wrong air / fuel ratio at idle. Fiddle with throttle stop screws at your peril!!!!!!! All of that sounds fairly technical. I have moved the throttle top screw ever so slightly and no idles at 600rpm quite steadily. When i have the money for a proper diagnostic i'll get it in. Thanks for the ideas chris i will get this looked at. Quote Link to comment Share on other sites More sharing options...
Mattross1313 Posted April 13, 2012 Share Posted April 13, 2012 Im going to be checking out the throttle cable tomorrow. Coming back to the AC comment earlier in the read. The car was warm idling this morning at around 3-400 rpm, so i turned on the air con, the revs went up to around 1100rpm. So if the car was idling at a normal range....the jump to 1100 is about right with aircon. Other than that im stumped..... Matt Quote Link to comment Share on other sites More sharing options...
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