Live data readings differ from my two trucks same engine.
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Live data readings differ from my two trucks same engine.
Alright guys I have a tricky two part question so I have a 2001 Dodge Ram 1500 5.9 2wd runs like a top and a 1997 Dodge Ram 1500 5.9 4x4 few issues so I was checking live data to compare both cause the 1997 has had issues with weird idle on start up and kinda like a slight miss at idle in gear so the 1997 live data shows 14.5 for the tps (it’s brand new) but the 2001 shows 12.5? Could that affect the idle? Also the 1997 shows incomplete for catalyst and the 2001 shows complete? What would cause that?
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Joined: Apr 2010
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From: Clayton MI
So long as the PCM knows what the "zero" value of the TPS is, the 'actual' value doesn't really matter. PCM only uses it as a reference for if the throttle is closed or not. Did you reset the PCM after replacing the TPS? It needs to re-learn the zero value.
catalyst incomplete just means the engine hasn't been thru enough drive cycles for it's monitor to be 'ready'.....
catalyst incomplete just means the engine hasn't been thru enough drive cycles for it's monitor to be 'ready'.....
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Joined: Apr 2018
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From: Missouri (LOZ Region)
Hmnmm. Is the engine warmed up when it's giving you an incomplete reading? It's been a LONG time since I've messed with this, but I'd guess if it's incomplete, it's really saying that it's in Open Loop? In Closed Loop, the Oxygen Sensors before and after the Cat tell the computer to richen or lean out the fuel mixture. In Open Loop, it's running the engine at a fixed, fairly rich as I remember it, mixture.
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Joined: Apr 2010
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From: Clayton MI
No, it's an emissions thing. The engine can drop into close loop within 2 minutes of starting, even stone cold. I think the PCM wants coolant temp at like 108 degrees though..... but, O2 sensors on these trucks are heated, so, they are 'ready' pretty quick. The cat being incomplete just means the 'calibration' process for that particular monitor isn't done yet.