Car wont start! Help!
#61
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is your fuel injector harness even plugged in?
the white/red 12v wires for the injectors are shared with the CAS and other components, like the ECU, powered directly from the MAIN relay. So if the CAS and ECU is working...
do you have 12v on the B+ in the diagnostics box?
the white/red 12v wires for the injectors are shared with the CAS and other components, like the ECU, powered directly from the MAIN relay. So if the CAS and ECU is working...
do you have 12v on the B+ in the diagnostics box?
you said you had no power at the injectors, but power at the CAS and diagnostics box. If that's really the case, then you need to power your injectors in order for them to fire.
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Okay, so basically i need to follow the red/white wire to the ecu to check for breaks, and also to the CAS and and Mass Airflow sensor? Or since I am getting power to the CAS then there is not a break in the wire between the injectors and CAS/ MAF?
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sorta. Brain's the better resource, but the ecu switches the ground side of the injectors, NOT the power side. The injectors have 12v on them all the time, and the ecu connects the other wire to ground when it wants the injectors to fire. Red/white sounds like a power wire, not a ground, but I don't have a wiring diagram in front of me.
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sorta. Brain's the better resource, but the ecu switches the ground side of the injectors, NOT the power side. The injectors have 12v on them all the time, and the ecu connects the other wire to ground when it wants the injectors to fire. Red/white sounds like a power wire, not a ground, but I don't have a wiring diagram in front of me.
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no. put the black lead to the head or something, any engine ground, and with the key to ON, unplug an injector and test the red/white wire side of the connector with the red lead for voltage.
if you have voltage, then the issue is probably the signal back to the ECU.
if you have voltage, then the issue is probably the signal back to the ECU.
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okay.
so the injectors have power, you get spark, but we're pretty sure the injectors aren't firing?
and the pump at this point IS running?
(please bear in mind that doing this over the internet with little to go on is hard. Trying to narrow things down here.)
so the injectors have power, you get spark, but we're pretty sure the injectors aren't firing?
and the pump at this point IS running?
(please bear in mind that doing this over the internet with little to go on is hard. Trying to narrow things down here.)
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hmmmm....
what happens if you unplug the TPS and try to start it?
and we are positive the fuel lines are crossed or something?
next thing I'd try is making sure the 4 wires from the injectors make it all the way back to the ECU.
what happens if you unplug the TPS and try to start it?
and we are positive the fuel lines are crossed or something?
next thing I'd try is making sure the 4 wires from the injectors make it all the way back to the ECU.
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With tps unplugged, same symptoms. Cranks but doesn't fire. Fuel feed line is going into the front of the rail, return like coming out of the fpr. If the fpr is bad what would be indicative? Are there any symptoms? I figure it would restrict the return flow. If, for example, the injectors themself are bad, but the regulator is good, would the flow out of the return line be the same rate as the flow into the rail?
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Is the ECU, coil pack, and several other ground wires bolted to the back of the intake manifold near egr? Are there any other grounds in the "rear of engine"? In the wiring diagram I linked, on page 8, it shows 3 different grounds to the "rear of engine" and on page 9 it shows 3 wires to a connector that go to 1 wire that grounds at the "right rear of engine". I can only find the 1 ground at the back of the intake manifold. Are there others?
Last edited by 94LagunaR; 04-12-2013 at 03:51 PM.