EVP test #'s What is causing code 34 in M

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Dec 16, 2021 | 03:16 PM

sandymane

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Joined: Oct 2016

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From: Houston/Sugar Land

EVP test #'s What is causing code 34 in M

Mine.............................................. ........Normal
VREF SIG RET. 4.84V................................5.0
VREF EVP 1.043 OHMS............... Less than 5K ohms
Sig RET EVP 10.42 OHMS............. More that 100 ohms

I am getting OBD1 code 34 in MEMORY ONLY
EVR - (O, R, M) EVP sensor is/was high - EVR
PFE - (O, R, M) PFE sensor is/was out of range - PFE

I know how to clear memory
I applied vacuum to the EGR and the truck died as it should I believe.

Dec 16, 2021 | 05:07 PM

torq'ta 5 8

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From: N.W. Alabama

329.4k Ohms is way out, unless that was 329.4 Ohms
old fuel injection says, need to check closed voltage, on EVP

Dec 16, 2021 | 06:21 PM

sandymane

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From: Houston/Sugar Land

With all my new found knowledge over the past few days, I guess i'm losing it. Please see the new ohms numbers in post one. Thanks for the help bud I really need it on electrical and decimals. Is this the current procedure to check the EVP for closed voltage? "At idle with the engine warm, pull the vacuum hose off the egr valve. Nothing at all should happen because at idle there should be no vacuum present at that hose. If you pull it off (hold your thumb over the hose), and the idle smooths out, then it's likely either a problem with the egr vacuum switch (firewall), the wiring harness has an issue, or the ecu is sending an errant signal"

Earlier I did pull the EGR green hose off with a cold running engine, and there was was vacuum at the vac hose.

Also getting a pretty strong fuel smell on start up of a cold engine.