I have a 2002gmc sierra 2 wheel drive 5.3lit 8 cylinder

Part of the problem, code 1357 means random misfire, P8 means cylinder number 8. Your engine is an 8 cylinder, right? When the engine light
is blinking it means that the misfire is starting to do damage to the catalytic converters. With the engine getting hot, check the coolant level when the engine is cool to make sure it is full. Check it by taking off the radiator. cap and looking into the radiator. Be careful when taking off the cap. You could have a bad head gasket causing your problem. Have a mechanic have a look before alot of damage occurs.

The service engine soon light is on ? Did you have it checked for DTC'S - diagnostic trouble codes ?

uh oh computer malfunction

www.engine-light-help.com/generic-engine-check-light-codes.html

The problem may be the engine coolant sensor. If the sensor fails the engine will stop when normal operating temperature is reached . When engine is cold it will start.

Post your code s here and I can look them up in my service manuals .

If there is an Auto Zone or any other large auto parts store, have them scan the truck for the DTC codes. The DTC codes will identify the Issues that needs to be addressed in your engine and transmission that has set off the service engine light on. Once the issues has been resolved, the light will reset it self after the third start up and after 40 start up will erase it self from the history as long as there is no additional issues. Good luck and hope this helps, Shift suddenly become very hard. When going from park to either reverse or drive it slams into gear. 1-2 and 2-3 shifts are also harsh. All gears seems to work. Problem may be intermittent: Check TPS for smooth electrical response. If the response is jumpy or erratic at all, replace TPS.

it's a coil- these are commonly going out on audi's...it happend to me. it's like you are running on 2 cylinders instead of 4- you need to get it replaced- it's about 75 bucks.

Like to other guy said, give it a tuneup. Also try SEAFOAM to clean carb up of slug. Also check to make sure the butter fly for the choke has not come loose, causing it the choke it down. Failed choke pull-off.