20 Most Recent 2002 GMC Sierra 3500 Questions & Answers

Sounds like a grounding issue, check all the grounds on the Truck, or you may have to change the signal switch!

The problem is probably manyfold - a general deterioration of several aspects that add up to poor cold starting, a time that makes greater demands of the systems than any other time and only checking A to Z and repairing as you go will restore reliable cold starting. A cold engine needs a good cranking speed without depriving the ignition system of enough current to produce fat blue sparks at the spark plugs. Worn spark plugs require considerably more voltage to make a spark... The fuel system is next - fuel must be presented into the cylinder in a form that will readily burn and that means there should be sufficient fuel in a finely atomised spray so ensure the fuel pressure is correct and the injector spray patterns are good and the temperature sensors are ok. The engine condition is important, especially the intake valve seatings...

So , what about it ? What would you like to know , what part to change or how to diagnose ? (TEST)

check battery voltage both sides of stop light switch if if none check fuse , if one side only replace switch, if ok check voltage at light bulb holder if ok check bulb or earth system

Are the bulbs good ? Did you check for B+ voltage at the lamp sockets ? The passenger and the driver side get B+ voltage from the same place . Do you know how to do automotive electrical circuit testing with a DVOM - digital volt ohm meter ? Do you know what a wiring diagram is ? How to use it to find testing points in a electrical circuit ? Here is a web site for free wiring diagrams . http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model and engine size . Under system click on lighting , then under subsystem click on exterior lighting . Click the search button , then on the blue link's . The light's on the fenders are maker lamps ! Now here is were it gets tricky , if you look at the diagram on the right you will see the back up lamps are controlled by the BCM - body control module . The BCM gets a turn on signal from the PCM -engine computer , because the transmission range switch is a input to the PCM . This can be very confusing to someone you doesn't deal with this sort of thing . Hooking up a scan tool that can view this type data would be the easiest way to trouble shoot . ECM Inputs and Outputs Diagnosis Electric Testing Techniques You Need to Know

What is it doing ?

It is inside the cab on the passenger side. First you remove the plastic coverings starting from the floor. You will find a box with the fan on the back and the heater core in the middle. Open the box and remove the two hoses. I would go to the junk yard and practice removal and then install the donor part.

have throttle body serviced may need to be cleaned

If the Obd says No Link you have a power issue.

Shift solenoid. Hard to tell with one is bad because there is no way to really test them. However your may have 4 solenoids in your transmission.

The starter is where the engine and transmission bolt together, under the exhaust manifold.

The first thing you would need to know is why it won't start on its own.It could be the key switch or a list of other things.Try to narrow down the choices, fuel, ignition, or compression.

sounds like the injectors are clogged