TSB EG047-04 Applies to Gen I Prius?

[treet007]

Hi there. My 2002 Prius with 129,146 miles (and a new HV battery) has a strange problem in which my mechanic believes the PCM needs to be reflashed per TSB EG047-04. Attached are the check engine codes (P3190 and pending P0302) and the diagnosis. All of the possible causes were eliminated, so the only answer was to reflash the PCM.

Question: Does TSB EG047-04 apply to Gen I Prius? I have only read about this TSB being applicable to Gen II Prius and other vehicle lines, not Gen I Prius.

Thanks in advanced.

[Patrick Wong]

It's not possible to "reflash" the Classic engine or hybrid vehicle ECUs. This is why a number of Classic owners had to get new engine ECUs installed as the firmware evolved (my 2001 also benefited from this.)

When was the last time your iridium spark plugs were replaced? If not recently, I'd start with a fresh set of correct NGK or Denso iridium plugs. Then, clean the throttle body interior and throttle plate. Make sure the engine oil is 5W-30 viscosity and not overfilled.

Hopefully this will get rid of the P3190 and P0302 DTC. If not, then you'll have to replace the engine ECU with the latest revision, which will probably cost ~$300 if you buy it at a salvage yard. TSB EG011-03 provides more info, I have posted this previously.

Also see:
2001, 2002, 2003 Prius P3191 and P3101, out of gas

[bwilson4web]

This is what I do to clean my throttle plate each fall:

Cleaning Prius Throttle

Bob Wilson