vn misfire , higher than normal idle

[andy71]

Any thought on what would cause my 90 mod V6 to suddenly start idling 700rpm higher after a battery change. used to idle at 600rpm now idling 1200rpm.
The motor has a fair miss aswell between 3500 to 4000rpm then takes off.

Prior to changing out the battery I noticed there were two loose bolts on the passenger side ex manifold the one with the ox sensor. Tightened these up . The car actually seems to run slightly smoother now but not too sure what they should idle at.

Thanks in advance for your replys

[Shoxer]

On the 5ltr i know when the battery has been discconnected you have to start the car and hold the RPM at 3,000 for 10seconds. I think that calibrates your idel speed.

[immortality]

you need to reset the idle, as mentioned above, disconnect the battery for for 30 sec. reconnect, start the engine and rev to 3000rpm for 10seconds. then let the throttle go and it should reset the idle. do this with the engine up to running temp and all accesories turned off. if this fails, pull the TB off and give a good clean, especially the IAC valve and associated passages then try the above again. also check for fault codes if this doesn't cure the problem(search for threads elsewhere in this forum on how-to)

[dans_vz]

hey guys, where is the IAC valve located on a vn/vp?

[immortality]

on the side of the throttle body, next to the firewall on the V6, hasa four pin plug on it