91 4runner wont start, injectors not working
#1
91 4runner wont start, injectors not working
i picked up a 90 or 91 4runner 3vze 5spd 4wd that the motor had already blown up in, he swapped in a newer 3vze in and could never get it started, iv replaced the main relay, fuel pump, dizzy, plugs and wires, and the main relay, when i got to turn it over it starts for a second or two then shuts off and wont start again till i turn it all the way off then it still dies every time, if i unplug the cold start injector it doesn't even do that much. i hooked up a scanner to it and it is getting a no rpm to crank sensor code 12, which is why i got the new dizzy but still the same i had gotten a diff ecu from a wrecking yard but its the wrong one. the only things i can think of is the COR or the ecu, any ideas? thanks.
#3
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Punctuation would help, but it sounds like you installed what you knew was the wrong ECM. Any reason to think it will work?
Since you're getting a code 12, I would take a cue from the FSM and look at the NE and the STA signal at the ECM.
But if those signals were out completely, I would expect no ignition at all. A common cause of "start and run a few seconds" is a problem with the VAF switch to the COR. Fortunately, this is trivial to diagnose: hold the fuel pump on with FP+ terminal in the diagnostic plug; if it runs then it is either the VAF or COR.
Otherwise, I would still suspect the ECM is telling the truth, and go from there rather than replace parts randomly.
Since you're getting a code 12, I would take a cue from the FSM and look at the NE and the STA signal at the ECM.
But if those signals were out completely, I would expect no ignition at all. A common cause of "start and run a few seconds" is a problem with the VAF switch to the COR. Fortunately, this is trivial to diagnose: hold the fuel pump on with FP+ terminal in the diagnostic plug; if it runs then it is either the VAF or COR.
Otherwise, I would still suspect the ECM is telling the truth, and go from there rather than replace parts randomly.
#5
never mind im stupid, so i put a jumper in the b+ to fp and the fuel pump turns on with the key but it still starts for a second then dies, its getting fuel to the fuel rails but the injectors are not pulsing. what other than the ecu controls the injectors?
"Punctuation would help" ya i spell werds rong too lol. and thanks for the help!
"Punctuation would help" ya i spell werds rong too lol. and thanks for the help!
#6
Okay so it was the ecm/ecu i plugged in the 91 specific ecu and it fired right up! thanks for the grammar lesson but i think i still suck at it.
edit, the wrong ecu i got was for a 90 which is what the last owner said it was.
edit, the wrong ecu i got was for a 90 which is what the last owner said it was.
Last edited by zero503; 10-03-2011 at 06:13 PM.
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