'94 Code 71, EGR Bypass and redneck technique.. (1 Viewer)

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Jan 26, 2009
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My heads spinning with all this egr info.

So looking for a few simple answers regarding this..

which resistor/wattage seems to be the right choice for the 94 OBD1 trucks? (I saw 1k ohm but never mentioned wattage, saw many different wattage ranges when I went to order some)

Or does the paper clip suffice?

Thank you in advance!!
 
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Jersey, 07740
Still curious if none of you have to get emissions checks? If so, do you pass? Reconnect? Or what? Thanks.

its possible to pass emissions with no egr, i have done it before. because my truck was obd 1 it got the tail pipe test and i didnt have any issues passing, there was also no visual inspection of the emission equipment but i doubt that anyone would notice it
 
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So I did this EGR redneck bypass on my 94 with a shortened paper clip (couldn't confidently get a short wire to fit into the plug contacts) and all was good. Or so I thought.

Then after a few short drives I got a CEL for about 15 seconds and then the light went back off. Once I got home I decided to pull the codes and had code 25 (lean condition).

I cleared codes and took a longer drive.. After about 5 minutes on the highway the CEL came back on. Once home, I read the codes again and it showed code 71, but no code 25.

I reset the codes again. Took it for a another highway drive and only got the code 71 (no code 25)

I continued to check the temp of EGR tube after each drive, the tube was only slightly warm to touch, and not hot at all. (so I'm assuming it's not stuck open?)

So my questions are

Would a 1994 California fzj80 be different from other states? My 80 came from California. Would this mean I need a resistor (like obd2 80s need) instead of a simple jumper?

Could bypassing the EGR cause a brief code 25 lean condition?

Perhaps I should put everything back as stock, and start inspecting and cleaning the actual components of the EGR instead of bypassing to see if the code 25 returns. This code has never been present before the EGR mod and only popped up for a few seconds.

Thanks guys for any info. Greatly appreciated.

Kevin
 
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So I did this EGR redneck bypass on my 94 with a shortened paper clip (couldn't confidently get a short wire to fit into the plug contacts) and all was good. Or so I thought.

make sure that the paperclip is making good contact with the pins in the connector,

I continued to check the temp of EGR tube after each drive, the tube was only slightly warm to touch, and not hot at all. (so I'm assuming it's not stuck open?)

the tube will always be warm due to its location and being bolted up to the head, if the egr was open or partially open the tube would be hot

So my questions are

Would a 1994 California fzj80 be different from other states? My 80 came from California. Would this mean I need a resistor (like obd2 80s need) instead of a simple jumper?

It should not be different cali or fed emissions, just the jumper wire should suffice

Could bypassing the EGR cause a brief code 25 lean condition?

No, probably the o2 sensors starting to go, the ecu is looking at the o2 sensors for fuel trim feedback. egr is emissions only and is used to control nox by cooliong the combustion chamber

Perhaps I should put everything back as stock, and start inspecting and cleaning the actual components of the EGR instead of bypassing to see if the code 25 returns. This code has never been present before the EGR mod and only popped up for a few seconds.

check the o2 senors. for what its worth i have driven my truck around with a 25/26 code for a while with no problem. connector for the o2 sensor got corrosion in it so after a wire repair and ne sensors no codes

Thanks guys for any info. Greatly appreciated.

Kevin

responses are italicized
 
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responses are italicized
Thanks that makes me feel a little better.. I will do... I replaced my both 02 sensors a month ago with Denso sensors. Only to find out I had a bad wire in the o2 circuit and probably didn't need O2 sensors to begin with (lesson learned). Once the wire was fixed I haven't had any 02 codes since (until tonight).
 
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Thanks that makes me feel a little better.. I will do... I replaced my both 02 sensors a month ago with Denso sensors. Only to find out I had a bad wire in the o2 circuit and probably didn't need O2 sensors to begin with (lesson learned). Once the wire was fixed I haven't had any 02 codes since (until tonight).

check farther up the wire harness from the connector for any additional issues in the harness. i replaced pins in the connector only to fine someone else had done a "wire repair" that consisted of electrical tape and a poor soldering job so i had more wire repairs to do. the harness that had a problem was the rear sensor, looks like the harness was rubbing on the front ds and was poorly repaired after that
 
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i did the egr bypass myself today on my 94. Not sure why everyone uses a paper clip or a wire jumper. Just cut the wires on the egr side of the connection and splice them together. unless you want to hook it back up again some day.

WP_20171123_17_53_14_Pro.jpg
 
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Anyone have a link for a guide to do this on a 96? All of this is kind of confusing, everyone seems to have their own twist to it, not sure which way to go. :S
 

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