04 Sierra bogging down?

[Wyatt Kokoszka]

Starting yesterday, the 04 is bogging down while coming to a stop. RPMS drop below 500 and it start missing really bad then after a few seconds it comes back up. Tried a new throttle body and cleaning the MAF to no success. Truck has 180k on it with a new trans, fuel pump and torque converter at 170k. Plugs , coils and wires were done at 160k. Any ideas what else might cause this?

[CamGTP]

I couldn't properly diagnose this problem without having a scan tool hooked up and possibly a fuel pressure gauge just to make sure I can see what is going on.

 

So I'm not sure what I can really tell you at this point.

[Wyatt Kokoszka]

28 minutes ago, CamGTP said:

I couldn't properly diagnose this problem without having a scan tool hooked up and possibly a fuel pressure gauge just to make sure I can see what is going on.

 

So I'm not sure what I can really tell you at this point.

I can tell you fuel pressure is normal, fuel trim is -4.7 long term with small short term adjustments less the 2. Pulling .62 inhhg at the MAF and rear o2 mil is on

[tlaw91]

Crank position sensor?
Also did you relearn idle when you replaced the throttle body


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