2000 454 rough idle and acceleration while cold

[00CrewCab]

I’m stumped and hope someone can help. 2000 454 k2500, hard starting, will crank forever unless you give it some gas and it’ll stumble to start, but once it does it idles at 750-850 rpm (normal?) but seems to have a misfire and you can smell gas out the exhaust. While it’s still cold (100-120 on gauge) it stumbles and backfires on acceleration 1000-2500 rpm then clears up and drives fine. Fully warmed up it’ll start with zero issues and drive perfectly fine. Had a pending code for too rich one bank one at 1500 rpm, cleared code and hasn’t come back (about 500mi ago). What should I be looking for? I planned for a full tune up, basic sensors, all filters, plugs, wires, cap and rotor, and coil pack(s?). Truck isn’t driven daily, I’ve got a work car, but it’s used for towing on weekends and I don’t want to be stranded away from home, thanks!

 

[Spareparts]

My first guess is injectors.

 

[ChRoNo16]

Plugs wires cap and rotor make sense, filters ok- esp fuel filter if this sits. I would run some fuel system cleaner through it. Gas gets nasty quick these days.

I wouldn't jump to sensors right off, unless you find one thats bad, but check your O2 sensors, make sure they are working.

 

[00CrewCab]

Plugs wires cap and rotor make sense, filters ok- esp fuel filter if this sits. I would run some fuel system cleaner through it. Gas gets nasty quick these days.

I wouldn't jump to sensors right off, unless you find one thats bad, but check your O2 sensors, make sure they are working.

How do I check 02 sensors? No codes on the truck so I kinda just figured they were working lol

 

[ChRoNo16]

I would have to say the best option is to pick up a haynes repair manual, it should have instructions, but making sure you have voltage at the connections and then checking the resistance of the sensor should tell you for sure that its working well

 

[fancyTBI]

I would have to say the best option is to pick up a haynes repair manual, it should have instructions, but making sure you have voltage at the connections and then checking the resistance of the sensor should tell you for sure that its working well

Haynes is garbage. The service manuals are on the forum for free.

 

[Grimpalahat]

What's a good data logging/scanning software/tool for these trucks?

 

[Schurkey]

I would have to say the best option is to pick up a haynes repair manual,

Haynes, Chilton, Clymers--they make excellent emergency toilet paper.

What's a good data logging/scanning software/tool for these trucks?

I use a Snap-On Solus Pro. There's other possibilities. And using a scan tool to verify sensors, computer outputs, fuel trims and misfire counts is enormously faster, easier and does a better job than using a multimeter to check sensors individually.

Don't forget to verify fuel pressure at prime, at idle, and under load.

 

[Erik the Awful]

How do I check 02 sensors? No codes on the truck so I kinda just figured they were working lol

In my experience, O2 sensors rarely throw codes. Check your O2 sensor voltage with the engine revved up to about 2000 rpm. You should see the O2 sensor voltage swing between high and low (0.1v to 0.9v) at least seven times in ten seconds. A scan tool is the easy way, but you can backprobe the sensor with a meter if you need to.