About 3 months ago my truck started to surge when idling, jumping from 300-1000 rpm and even died on me once at a stop light. I cleaned IAC and check the TPS voltage and reset the computer. All seemed well but it will still surge a bit, fluctuating 100 rpm or so.
The surging started up again about 3 weeks ago, so I changed the plugs and installed a new set of injectors since I had a set laying around and again reset the computer and seemed to run fine but would still surge about 100 rpms or so.
Well on the way home a few days ago, I was driving about 60mph and "all of a sudden" my truck paused, like I had hit a speed limiter, and the service engine light came on. Pulled over and got out while it was still running, and it was pouring black smoke out of the exhaust. This was with the service engine light on. I turned my truck off and turned it back on and all was fine, except the 100rpm surge. Even took it to autozone to get the codes read but there weren't any. They said the light has to come on and stay on for a code to be read.
It now does this to me 3 times in the last couple of days, and died on me 3 times in a parking lot. And the bad 300-1100 rpm surge is back.

 

Need more info.

How many miles?

Last fuel filter change?

Happened after a fill-up?

Do you have a ECU chip?

Changed the throttle body? MAF?

It could be fuel pumps, clogged fuel filter, contaminated fuel, etc.

We need more info to help!

 

Last fuel filter was 2500 miles ago.

Engine ('02) has 15k miles on it, but truck has a hair over 100k (O2 sensors are original).

I have a SCT chip for 4lb lower, volant air intake and custom exhaust (carsound cats and dynomax mufflers).

Plugs are TR6's gapped at .036 which I replaced along with the injectors a week ago.

Throttle body came with the engine and MAF is just over a year old.