EGR malfunction Code 71

logicalman · 07-29-09, 10:12 AM

my check engine light stays on when i do city driving but when i drive on the freeway for about 30 mins it goes off. i've cleaned the temp sensor, and the vacuum modulator filter a few times now and it still comes on during city driving. can you guys tell me what else can i do?

i've been looking into putting a resistor into the plug but i dont know what plug to put it into.

shajbot · 07-29-09, 10:24 AM

The plug that goes into the EGR temp probe, it looks like a mini o2 sensor goes from the the bottom of the whole EGR module on the side of the intake plenum...if you have a V8. Put a 10K resistor over it.

$C300 · 07-29-09, 05:24 PM

if i remember correctly there is only one plug by the EGR if its a 300, its right by the round vacuum actuator

logicalman · 07-30-09, 11:53 AM

Quote:

Originally Posted by $C300

if i remember correctly there is only one plug by the EGR if its a 300, its right by the round vacuum actuator

is this the actuator?

bangdangvn · 07-29-09, 10:45 PM

was it hard to remove the egr valve with the pipe attach to it? I've tried but do you have to pry the bar away from the valve to remove?

CLNSC3 · 07-30-09, 01:36 AM

Quote:

Originally Posted by logicalman

my check engine light stays on when i do city driving but when i drive on the freeway for about 30 mins it goes off. i've cleaned the temp sensor, and the vacuum modulator filter a few times now and it still comes on during city driving. can you guys tell me what else can i do?

i've been looking into putting a resistor into the plug but i dont know what plug to put it into.

A couple of years ago I had the same code, that time the modulator itself was the problem, replaced it and that took care of the problem.

Fast forward to a few weeks ago and I got code 71 again. I removed the EGR pipe and cleaned it out, no problems since!

-Josh

logicalman · 07-30-09, 12:03 PM

Quote:

Originally Posted by shajbot

The plug that goes into the EGR temp probe, it looks like a mini o2 sensor goes from the the bottom of the whole EGR module on the side of the intake plenum...if you have a V8. Put a 10K resistor over it.

you are sure if you put a resistor into the temp probe it will stop the check engine light?

Quote:

Originally Posted by CLNSC3

A couple of years ago I had the same code, that time the modulator itself was the problem, replaced it and that took care of the problem.

Fast forward to a few weeks ago and I got code 71 again. I removed the EGR pipe and cleaned it out, no problems since!

-Josh

seems like alot of work trying to take out the EGR pipe. how did you do it? imma try spraying some cleaner into the pipe and blowing it out with compressed air first.

Ali SC3 · 07-30-09, 12:36 PM

you dont have to take anything out to put in the resistor. on an sc300 it takes like 5 minutes to disconnect the old plug, cut off the wires, attach a resistor, and plug back in.

the ecu will be happy 100%, but as for solving the problem why it went off in the first place, it will not really do anything. but who cares if the egr works properly as long as its there. you got that code for having insufficient flow, which in my book is not a bad thing.

logicalman · 07-31-09, 12:00 AM

Quote:

Originally Posted by Ali SC3

you dont have to take anything out to put in the resistor. on an sc300 it takes like 5 minutes to disconnect the old plug, cut off the wires, attach a resistor, and plug back in.

the ecu will be happy 100%, but as for solving the problem why it went off in the first place, it will not really do anything. but who cares if the egr works properly as long as its there. you got that code for having insufficient flow, which in my book is not a bad thing.

ok so where do you put the resistor? on the temp sensor plug?

$C300 · 07-31-09, 02:34 AM

Quote:

Originally Posted by logicalman

ok so where do you put the resistor? on the temp sensor plug?

Ya thats it, im probably not calling it by its proper name it might be a distribution block, but it should be right under that, you can ither plug a resister in, or cut the wire in solder a resister in.

Ali SC3 · 07-31-09, 11:16 AM

Quote:

Originally Posted by Twan0690

How do you know if it is stuck open or closed?

if the egr is stuck open your car will not run... at all.
EGR only opens in 4th or 5th gear above 40mph (approximately, cant remember)
If It opens before then your car will not hold a smooth idle and run terrible.

it is almost always "stuck closed" as they call it.
what they really mean is so much doodoo is stuck in the EGR pipe that it actually gets clogged, not allowing air to pass.

Quote:

Originally Posted by logicalman

ok so where do you put the resistor? on the temp sensor plug?

yes, there is a probe that sticks into the base of the EGR pipe where it meets the intake manifold. it is a grey clip and it is right between the back of the intake manifold and the firewall. its best to get someone with small hands to do it.

AD_SC3 · 07-30-09, 10:59 PM

How do you know if it is stuck open or closed?

AyDee · 07-31-09, 01:18 AM

I want to know too, I have a SC400 94
help?

Mortal300 · 07-31-09, 01:44 AM

Egr mod!!

AD_SC3 · 07-31-09, 08:52 PM

Cool I reckon mine is closed. So I guess that would be the same as a block off plate?