Shakey idle and sluggish take off

[ryan445]

Wires, rotor and and coil are done. I noticed on start up and high idle, the computer was hunting the rpms a little. Maybe relearning with the new coil? It eventually smoothed out. Idling a little smoother. But still has a stumble. Will do the fuel filter later today or tomorrow and go grab some premium gas and put the treatment in. I scanned it to see if throttle body code has stayed away and it has this far. Here is a link to a vid I took you can see the stumble when I gave a little it and when it idles down.

PXL_20260523_145431353.mp4

drive.google.com

 

[rusty ol ranger]

Wires, rotor and and coil are done. I noticed on start up and high idle, the computer was hunting the rpms a little. Maybe relearning with the new coil? It eventually smoothed out. Idling a little smoother. But still has a stumble. Will do the fuel filter later today or tomorrow and go grab some premium gas and put the treatment in. I scanned it to see if throttle body code has stayed away and it has this far. Here is a link to a vid I took you can see the stumble when I gave a little it and when it idles down.

PXL_20260523_145431353.mp4

drive.google.com

Have you checked for vacuum leaks?

 

[ryan445]

Have you checked for vacuum leaks?

I have with the good ole spray carb cleaner at lines and stuff lol.

 

[SenorNoob]

My idle takes a couple weeks to settle down after I pull the battery cable. YMMV.

 

[PetroleumJunkie412]

The tps sensor on a 2.9 has an eccentric on the bottom bolt. You move it in and out for your "calibration"

You're showing some signs of ecm capacitor failure, but don't let me lead you down the wrong path.

 

[ryan445]

The tps sensor on a 2.9 has an eccentric on the bottom bolt. You move it in and out for your "calibration"

You're showing some signs of ecm capacitor failure, but don't let me lead you down the wrong path.

If it turns out to be. It will be the second time I've replaced the ECM in the 17 years I've owned this truck. When I first got this truck it always showed two codes. Egr stuck open when it wasn't and another EGR related error. Truck ran fine until one day it lost all power, would barely move and was running so rich I could smoke out the neighborhood. After lots of trouble shooting I ordered this OEM ECM from eBay and fix all issues. So it could be this one is just slowly starting its demise.

 

[ryan445]

Does anyone know how to test the MAP sensor? I unplugged it while idling and it did surge on the idle a little but, I noticed when I blipped the throttle, it didn't fall flat on its face and when returning to idle is also didn't stumble as much. Could smell it went to the rich side when I unplugged it.

Also definitely got a leaky injector somewhere. When I went to bleed the pressure off to do the fuel filter. There was little to not pressure in the line.

Edit: Map seems fine. I did the ole suck on the line and see if engine responds test. My multi meter doesn't read hz so it the best I can do.

 

[ryan445]

Unless I'm missing something in those photos, that cap and rotor doesn't look much worse than what I usually pull off mine when I finally get around to changing it, and electrical misses haven't been a problem for me. The bad plug wire sounds like it could have been an issue. Still, one bad plug wire would not explain 3 fouled plugs.

If you've been running fuel system cleaner regularly you may not have dirty injectors, but if you're a DIY'er this is worth knowing about. If everything electrical checks out okay but you still have cylinders running rich and lean, this may be worth doing. You'll find YouTube videos showing different versions of this process. You hold the injector open using a 9v battery and test leads. 12v will damage the injectors. Then using something like a syringe you force cleaner through them. First you can test if they don't close completely by leaving the battery off. Catch what sprays out the pintel end so you can see if it's dirty and see when the cleaner flows through clear. I've used throttle body cleaner because it's better around electrical components than carb cleaner, but you'll see videos with people using carb cleaner. A couple of years ago you could get a kit with new screens, pintel caps and o-rings for about $25. The Injector Shop has an EBay store.

@89longbed

Is this the kit your referring to?

RockAuto | All The Parts Your Car Will Ever Need

Auto Parts for Your Vehicle at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.

www.rockauto.com

Thinking I will give it shot, it will be a chance to learn something new. Also, it will allow me to see which ones are good or bad and see if that coincides with the cylinders that had the fouled / lean plugs and if one or two don't clean up I can buy just that one or two.

Do you clean first and then rebuild the injectors with the new gaskets and caps?