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Hey!!

I have completed my installation of my double-roller timing chain, performance waterpump, and my 180 degree thermostat!! She's runnin great! ...

My question tho, I've driven it to work, and it runs wonderfully!! No more choppy idle, no more clanking from the chain, but... She still idles relatively low. Today at start up, about 800-900rpms, and after she was warm, about 450-500rpms!! Whats up with that?!

It's as low as when the chain was going bad!! Any input would be wonderful! Thank you!
 

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I have a 1996 dakota and when i first turn it on it runs great but when i go to start up again the idle drops down to around 400 and just dies.I have replaced idle sensor dist cap plugs and gaskets in head,,,,,,,,,,,,,,,,is there anyway of tuning up the idle speed or do I need to rpalce the TPS???
 

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I have a 1996 dakota and when i first turn it on it runs great but when i go to start up again the idle drops down to around 400 and just dies.
Cold start is ok? What is the idle rpm on the first cold start?
Is yours an automatic? Idle should be around 600rpm for an automatic.

I have replaced idle sensor dist cap plugs and gaskets in head,,,,,,,,,,,,,,,,is there anyway of tuning up the idle speed or do I need to rpalce the TPS???
Didn't realize that the magnum V6 has an "idle sensor"..my 98 magnum V8
has an IAC (Idle air control) which is a two stage stepper motor controlled
by the PCM.
This is not a sensor..it is an actuator solenoid/motor which controls the amount of idle air coming in when the throttle position is CLOSED, so no
air is getting by the throttle plates and the air coming in to maintain idle has
to come in from a bypass passage on the throttle body..maybe that is plugged
or carboned up?

http://www.2carpros.com/articles/how-a-idle-air-control-valve-works


Replacing the TPS, unless it's incorrectly installed in the first place is
not likely going to change it and you can actually check the o/p
of the TPS sensor right on the truck with the engine not runnning.

Leaking vacumn in the intake manifold, or any vacumn related hoses
or even a loose hose to a PCV valve can cause a rough idle.

There is no manual adjustment "idle screw" on the throttle body like there used to be on the older carbureted models.
The PCM sets the idle speed depending on engine temperature, engine load and
whether it's an automatic or manual shift transmission.
 

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Hey!!

I have completed my installation of my double-roller timing chain, performance waterpump, and my 180 degree thermostat!! She's runnin great! ...

My question tho, I've driven it to work, and it runs wonderfully!! No more choppy idle, no more clanking from the chain, but... She still idles relatively low. Today at start up, about 800-900rpms, and after she was warm, about 450-500rpms!! Whats up with that?!
It will vary depending on whether you have an automatic or manual transmission. With an automatic, it needs to idle higher so that the
oil pump in the transmission can maintain pressure as soon as you
go from park thru neutral to D.

Startup should be around 1000 rpm for an auto tranmission.
Provided there is no load such as cranking front wheels (power steering]
pump working hard) or turning on A/C compressor, the idle should stay around 900 to 1000 rpm until the engine reaches operating temperature,when it should
drop down to about 600rpm.

The ECT sensor (Engine coolant temperature) will send in a voltage
based on coolant temp to the PCM. The PCM adjusts the idle rpm
via the IAC (Idle air control motor) This is not a sensor but an actuator
to allow more air to come in to boost the idle rpm.

The idle air is dependent on the following sensors in this order..
1. ECT
2. IAT (incoming air temp sensor in manifold)
3. MAP (manifold absolute pressure) sensor

any or all of these are required to be in good working order for the PCM
to determine the idle rpm when engine is cold and warmed up to thermostat
temp rating.
 
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