Wrench lights comes on the the truck runs rough and loses acceleration.

and it will have scanned for the trouble code so you can correctly repair problem

Get it scanned to see what code is stored in the PCM and come back and let us know

diaconnect the battery for 2hrs so it loses its memory-the wrench symbol means service is due not something wrong -Denny

Rough Running Engine - James on Engines #2 - Bell Performance

https://www.bellperformance.com/blog/rough-running-engine

Apr 21, 2015 - When diagnosing an engine with a rough idle, there are certain things that must be ... If the problem does not reoccur, the codes will be erased by the computer. ... when accelerating the vehicle, which causes a higher fuel demand. .... it was water in gas...added added Gas LineAntifreeze/Water Remover.

If this is a deisel then it's probably some sensor malfunction. It could be one of the sensors in the exhaust system or a simple electrical fault - I have been told it can happen if even just one brake-light bulb is broken

Throttle actuator system stuck closed. Throttle body valve stuck/tight

It's bad enough to have a steady engine light, but to flash...really not good. A flashing engine light means the vehicle is in "limp home mode". Enough to get you somewhere to have it fixed immediately.

All sorts of issues could be the cause here from plugged injectors, plugged fuel filter, bad spark plugs, bad coils. You need to find out what the codes are that are stored in the computer to provide more detailed clues as to what's going on.

Do you have a check engine light on? Is this a 4.3 with central port injection? If it's running real rich it might have a fuel leak inside the intake, either a fuel pressure regulator leaking or a feed line to the injector.

Well for one you already paid them $90.00 so make them fix it right. Second of all it could be many things. What are the codes? If your service engine soon light is on there are codes set. Does the car run fine when cold then as it warms up does it start to run rough and eventually die?