Diagnostic Code 43 and 71 on 1991 Toyota Pickup?

Getting details for this two digit codes is not easy.But here are details for codes 43 and 71,which is showing on your Toyota car model.

Code 43 says starter signal not reaching ECM. Are you push starting the truck? If not, might be a bad wire from the ignition switch to the computer.
Code 71 is low EGR gas temp. Could be the sensor signal is not reaching the computer but more likely the EGR valve is not opening. May be stuck/clogged, has torn diaphragm, or is not getting vacuum. I believe the vacuum is controlled by a thermal valve. Check to see that the thermal valve is getting vacuum from the intake manifold and opening to deliver vacuum to the EGR valve when the engine reaches operating temp.

See the block diagram shown below:------

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If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

For more car error code details and troubleshooting,see the list mentioned below:----

Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

OBD code P0172 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

DTC Code P0321 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

Error Code P0471 on 2007 Dodge Ram 3500?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

P0304 Error code on Dodge Neon?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

How to Clear OBD error Codes on Acura Car Models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 2.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html