93 4-Runner with a CEL Code of 71

[JLH911]

Anyone know where to start? I was told it could be the EGR Valve or the EGR Modulator. Anything else that it could be?

I did a search and didn't really come up with much.

Thanks in advance

[WristPin]

EGR VALVE MALFUNCTION--EXHAUST GAS TEMPEATURE BELOW SPEC. FOR EGR CONTROL
--EGR SYSTEM

--EGR GAS TEMPERATURE SENSOR/CIRCUIT


how does your engine run at idle? if it runs good at idle start with this:
when the engine is running, apply vacuum to the egr valve. if it dies the valve works. if nothing happens the valve is stuck closed.

do that, and ill type more later. im crunched for time...

[JLH911]

Originally Posted by WristPin

EGR VALVE MALFUNCTION--EXHAUST GAS TEMPEATURE BELOW SPEC. FOR EGR CONTROL
--EGR SYSTEM

--EGR GAS TEMPERATURE SENSOR/CIRCUIT


how does your engine run at idle? if it runs good at idle start with this:
when the engine is running, apply vacuum to the egr valve. if it dies the valve works. if nothing happens the valve is stuck closed.

do that, and ill type more later. im crunched for time...

Great, I'll try that, but it won't be till this weekend as this is my Dad's truck and that when he comes over.

I'll let you know!

[WristPin]

ok cool. remeber to check the FAQ!

here is a page you can acess when browsing the FAQ

http://personal.utulsa.edu/~nathan-b...18egrsyste.pdf

[JLH911]

Originally Posted by WristPin

EGR VALVE MALFUNCTION--EXHAUST GAS TEMPEATURE BELOW SPEC. FOR EGR CONTROL
--EGR SYSTEM

--EGR GAS TEMPERATURE SENSOR/CIRCUIT


how does your engine run at idle? if it runs good at idle start with this:
when the engine is running, apply vacuum to the egr valve. if it dies the valve works. if nothing happens the valve is stuck closed.

do that, and ill type more later. im crunched for time...

Okay, so we replaced the EGR Valve and the Modulator and we're still getting a code 71 after resetting the light.

What else could it be?