Originally Posted by tabetha
I would say you have a problem with the closed loop not falling, ie not cancelling out and leaving a lean cruise mix when it should not.
Closed does not work all the time, like accelerating, high speed/load etc.
If these go too lean the ECM will detect a stall about to occur and raise revs, check your CO at idle, which will NOT BE IN CLOSED LOPP AT IDLE anyway, at least it should not be.
Stu is a very very clever chap and knows what he is doing without a doubt, so it might also be wise to seek his help, but I would check baseline CO, set at around 2- 2.5%
tabetha
I disagree but see where your coming from.
No matter what you set teh fuelling to, if your throttle is closed it simply will never reach 2500rpm. If you go back to basics you will realise that to run a 2litre engine at 2500 rpm, you need an abundance of 1 item... AIR.
Look for:
1) Sticky throttle cable/butterfly.
2) ISCV sticking.
(Unplug it when teh idle problem is there, so what happens... If it stays high, give it a clump with a spanner, see if it drops.)
If unplugging it fixed it, its possible your ecu thinks the TPS angle is actually open when its not, as the ecu opens the ISCV once the throttles open.
(contrary to popular opinion. It does NOT stay closed... it stays open. )
Also, your ecu SHOULD be closed loop at idle of course, unsure why you think it shouldnt? Expect CO emissions with one of my chips to be <1%
(with HC's of sub 500 normally) no matter what injectors your conversion runs.