Santro eratic idling ... urgent help required

[Naweed]

A have tied up a trip to murree with a friend next week but today he told me that his car is giving problem so he might not go .. i need urgent help .. details as i he told me are given bellow

2006 santro with cng
works fine on cng
engine is a bit weak

idling problem started a year back
occassionaly it goes into low rpm where it stalls or shuts down and sometimes itss rpm race up like 2000 -2500
diagnostic test didn't reveal anything
iac was declared the culprit sometime ago .. it was replaced and no improvement

one odd thing when it reaches a mechanics garrage it doesn't give any issue ...

my guess

-- the problem lies in items/adjustments in throttle body
-- iac is dirty
-- iac is not housed properly
-- throttle position sensor requires adjustment
-- iac voltages or signals are disrupted (less likely or diagnostic would have brought out

i've excuded these (since the problem is not continuous

-- MAP sensor
-- Injectors

[waleed80]

Does it have a maf sensor

[Naweed]

i guess map and maf sensors are same ... yes it has one ... and this sensor senses the air pressure or it quality and inturn make the mixture lean or otherwise .. but this will not result n sudden stalling or high idle because those are controlled by iacv .. yes, it might result in a very lean mixture which increases fuel consumption and a smell of fuel

my areas of focus are iacv
the idle adjustment of tps
fitv .. fuel intake vavle (fon't know its location on santro but must be near intake or throttle body

[Naweed]

Problem resolved .. it was the position of TPS which needed to be adjusted and then everything smoothed out