‘95 5.7 runs poorly when warm. I’m reducing myself to being a parts-changer.

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xXxPARAGONxXx

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When your vehicle has warmed-up, the VCM is in closed-loop using the O2 sensor inputs for feedback to adjust the fuel trim. So, if your vehicle is running poorly after it has warmed up, you'll probably want to consider replacing the O2 sensors. I know you dismissed a closed loop issue, but still.
 

any4xx

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Well… God smiled upon me. The coil did the trick. Plenty of power now after driving all over the place for a good hour.

Now that THAT problem is solved I’m detecting an occasional, and ever so slight, stumble right off of idle. THAT is feeling like a fueling issue to me so I’m going to address that later. But for now it’s otherwise running great.
 

any4xx

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Over the next few weeks I will be replacing all of the other sensors. They are cheap enough and the truck is old enough that I don’t feel I’m wasting any money by doing so. Now that the big fire is out I can take my time and finally get to enjoying this new-to-me truck!

Thank you all for your suggestions.
 

HotWheelsBurban

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Coil is going in shortly. Dunno how I missed considering the module. That’ll be next if the coil doesn’t do it. Thank you.
I've been dealing with an idle and misfire issue with my crew cab, and I think I resolved most of it with replacement of the throttle position sensor and idle air control valve. Now it's down to coil, module and plug wires, or at least put some separators on the wires. But it doesn't do it near as bad as before I replaced those two parts.....
 

Schurkey

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Over the next few weeks I will be replacing all of the other sensors. They are cheap enough and the truck is old enough that I don’t feel I’m wasting any money by doing so.
O2 sensor(s)? Sure. They're known to not age well.

As for all the rest, the money you'll blow on quality sensors would get you near to buying a proper scan tool.

I'd rather have good used OEM-quality sensors than brand-new bottom-feeder Chinese-sourced sensors.
 

Komet

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I would suggest NOT replacing anything other than typical wear items (ignition, etc stuff you've already done) without testing them for proper operation. If nothing is wrong with your sensors and other parts, you're simply wasting time and money for parts that may not be manufactured to oem quality (regardless of what they say).

Stop putting a hurdle in front of yourself by saying things like 'I don't have a scanner' and start researching ways to get access to your data. I did it with my phone, aldldroid, and a cable from moates.net but there are many ways to do it.
 

any4xx

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I've been dealing with an idle and misfire issue with my crew cab, and I think I resolved most of it with replacement of the throttle position sensor and idle air control valve. Now it's down to coil, module and plug wires, or at least put some separators on the wires. But it doesn't do it near as bad as before I replaced those two parts.....
Something dawned on me later today. The ignition modules are absolutely prone to fail with heat. But my experience has always been that they either work great or not at all. I’ve never had a drivability issue related to an ignition module other than a complete no-run condition. The reason I started with the coil is that I HAVE had them run weak and change with heat. Cheap to replace in any event.
 

any4xx

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I’ve shopped online for OBD-1 scanners and have struck out countless times. As recently as this afternoon I found a part number for an Actron scanner, but kept striking out when trying to actually buy one.
All of my other vehicles are either pre-computer or OBD-2. Honestly, having an OBD-1 scanner would be convenient right now, but I’m not sure it’s enough of a priority for me to keep trying to source one. Sensors are easy enough to check individually with either a volt meter or an ohm meter.
 
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