94 F250 Code 334

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Sep 26, 2018 | 08:21 AM

steveamann

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From: Paris

94 F250 Code 334

The check engine light came on and it ran rough for about one mile went. Did key on Engine off test and got 334 10 512. Any help would be appreciated.
94 F250 5.8

Sep 26, 2018 | 08:56 AM

ZombieF150

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From: NC

334 = EGR closed valve voltage high
10 is a separator
512 = KAM test failure (Keep Alive Memory) which usually indicates your PCM is bad and needs to be repaired/replaced. That is the one I would concentrate on first.

Sep 26, 2018 | 09:16 AM

steveamann

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From: Paris

If the PCM is bad would it do it all the time or intermediate times?

Sep 26, 2018 | 09:42 AM

ZombieF150

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From: NC

Quote:

Originally Posted by steveamann

If the PCM is bad would it do it all the time or intermediate times?

It can give wonky codes and make the CEL come on yes from what I have read.

Most posts I have read about it, it is caused by 3 capacitors leakig due to age and corroding the connections. Some replace the capacitors themselves. I bought a reman PCM as I needed the truck on the road ASAP. I am pretty good with electronics and soldering but it was a time is money situation.

Sep 26, 2018 | 09:52 AM

steveamann

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From: Paris

Thank for the help.

Sep 26, 2018 | 09:57 AM

rla2005

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From: Kentucky

Code 512 can be triggered by removing the battery cable then re-installing it. Some do this to clear the stored codes from Continuous Memory. The proper way to clear CM codes is to start the KOEO tests, then remove the ground on the STI connector as the codes are flashing out.