I have a 93 22re Toyota sr5 pick up. Truck stalled while driving on freeway, got it towed to my house and have done some trouble shooting on the system. Gas tank is half full, motor will crank over fine but not start. If i hold open the volume air sensor door on the air box the truck starts and runs, i even drove it around the block and it ran OK. I tried a new volume air unit and it still will not start, i check the connector plug to the unit and it is getting 12 volts. what else should i check or change out ? Truck has 202,000 miles on it and was running fine before it stalled on me.Any help would be appreciated. Thanks

 

did you try another air flow sensor?

 

is that intake pipe not worn through?

 

Check opening circuit relay under dash buy kick panel think on passenger side . They had a corrosion problem/ heat opening the Maf all the way triggers the fuel pump/ecu efi open circuit wire.. tricking the truck to start thru full voltage ........you can also jump the connectors n toyotas to bypass this relay but its been a minute sense. Recall doing that

 

Tried a a new relay same thing will not start. there is 12 volts going to the relay, open the door all the way truck starts right up. What should i try next?

 

Opening circuit relay tested good
Check efi relay there wired in sequence on connection 4 then check tps for voltage battery on motor off

 

efi relay good. i have no voltage to tpi sensor with key off, and 4.0 on the green with yellow trace and 10.0 on the white with blue trace wires with key on.

 

could be the reference signal from the air meter not going to ecm -tells the ecm when to turn fuel pump on.

...so... when u hold the afm door open, it sends extra fuel = starts vehicle.

check ALL VOLTAGE SIGNALS from afm.

just a thought.

 

Try the jumper test I listed jump b+ and Fp with wire then key on reach under Mas sensor and push door open should here the fuel pump run try closing door se if it cuts off ......these are just some elimination testing this bypasses the ecu control over the fuel pump .

 

did that pump turns on. Voltage at connector to the mas sensor was 4.0 for ref. and 12.0 for power.

 

Hmm and your not getting any check engine lights/codes

 

Reference wire seems kinda low did it change when you swung the Maf door open say like 5 to 9 volts

 

No check engine lights or codes. Will recheck ref sig voltage and let you know.

 

Also check your ecu if you can get it open look at the circuit bored for hot spots mainly the little brown capacitors they bust and leak onto the bored causing problems . I no some of the capacitors are related to voltage flow to the maf sensor