No power to fuel pump. Searched and tested!
07-09-10, 02:13 PM
#1
No power to fuel pump. Searched and tested!
86 N/a.
No power to fuel pump.
I have jumped the 2 pin connector.
Tested main relay-Good
Tested all applicable fuses including engine fuse inside of car. All test good and even swapped out with other known good fuses.
Also tried to energize fuel pump by opening flap door on AFM.
Ran direct power to fuel pump and pump operates.
Main relay closes contacts when key is turned on and also when jumping the yellow connector. Took apart relay to verify that contacts are closing when powered and they are.
Ok 2nd guru's- Ideas?
No power to fuel pump.
I have jumped the 2 pin connector.
Tested main relay-Good
Tested all applicable fuses including engine fuse inside of car. All test good and even swapped out with other known good fuses.
Also tried to energize fuel pump by opening flap door on AFM.
Ran direct power to fuel pump and pump operates.
Main relay closes contacts when key is turned on and also when jumping the yellow connector. Took apart relay to verify that contacts are closing when powered and they are.
Ok 2nd guru's- Ideas?
07-09-10, 03:49 PM
#2
When you jumper the fuel check connector does the pump run with the key to on?
Did you look over the circuit opening relay to verify that it was putting voltage to the Blue wire with key to on when the above was jumpered?
You could also try jumpering the Black ground wire in the circuit opening relay to the Brown wire in that relay and turn the key to on. This is equivalent to jumpering the fuel check connector.
Did you look over the circuit opening relay to verify that it was putting voltage to the Blue wire with key to on when the above was jumpered?
You could also try jumpering the Black ground wire in the circuit opening relay to the Brown wire in that relay and turn the key to on. This is equivalent to jumpering the fuel check connector.
07-09-10, 04:14 PM
#3
HAILERS
Join Date: May 2001
Location: FORT WORTH, TEXAS,USA
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*********Main relay closes contacts when key is turned on and also when jumping the yellow connector.**************************************** ************************************************** *******************************************
Yellow fuel pump check connector does NOT close the MAIN RELAY. It closes the Circuit Opening Relay....by putting a ground on the circuit opening relay.
ENGINE FUSE is good 'cause you say the Main Relay closes when key to ON.
I'd pull the circuit opening relay and check for batt pwer on the black/white wire(s) with key ON. One of the two should have power with key ON. The other B/W will have power with key HELD to Start. Check both.
And or make a jumper wire and jumper b/t the middle B/W wire if it has power on it, to the Blue wire with key ON. Pump should run for sure, proving the circuit opening relay isn't pulling in OR has bad contacts inside it.
The BROWN wire should show a gnd on it with the vane in the afm pushed back OR with the yellow fuel pump check connector jumpered. If it does not, then the problem lies in the gnd for the AFM and or the yellow connector. Both share the same gnd point.
Or here's a cheap one: in the yellow connector, find the pure black wire (might be brown/black on early 87cars). Jumper from that wire to a known gnd point (bracket that holds the boost/pressure sensor on the chassis). Then key to ON. Pump should run. IF it does, then the gnd for the afm and yellow check connector has gone south for unknown reasons (located on top of the rear rotor housing.....intake has to be removed to access this gnd pt).
This post is just a repeat in many ways of Scath above. Try 'em all....one at a time.
Or try this: Pull the small trigger wire off the starter. HOLD the key to START. Pump should run. This is an alternate way of pullking in the circuit opening relay. That relay has TWO coils that can pull in that relay. This method uses the coil that has not been mentioned in the above. Starter won't turn for obvious reasons.
If good.........then with meter on ohms, see if it is indeed going to ground.
That otta keep you busy for the next couple of hrs.
FYI: The MAIN RELAY has zip to do with the fuel pump coming on. It can be in the backyard in the dog house and the fuel pump will run with key ON, yellow jumper jumped or key HELD to Start the pump will run as long as the key is HELD to Start. The fuel pump running is about all that will run though. Engine won't start with main relay not pulled in.
ENGINE fuse provides power to the circuit opening relay and to the fuel pump via that relay. Engine fuse also powers the coil in the main relay. If the main relay pulls in then the ENGINE fuse has to be a good player.
I have the ability to repeat myself alllll daaaaay long.
Yellow fuel pump check connector does NOT close the MAIN RELAY. It closes the Circuit Opening Relay....by putting a ground on the circuit opening relay.
ENGINE FUSE is good 'cause you say the Main Relay closes when key to ON.
I'd pull the circuit opening relay and check for batt pwer on the black/white wire(s) with key ON. One of the two should have power with key ON. The other B/W will have power with key HELD to Start. Check both.
And or make a jumper wire and jumper b/t the middle B/W wire if it has power on it, to the Blue wire with key ON. Pump should run for sure, proving the circuit opening relay isn't pulling in OR has bad contacts inside it.
The BROWN wire should show a gnd on it with the vane in the afm pushed back OR with the yellow fuel pump check connector jumpered. If it does not, then the problem lies in the gnd for the AFM and or the yellow connector. Both share the same gnd point.
Or here's a cheap one: in the yellow connector, find the pure black wire (might be brown/black on early 87cars). Jumper from that wire to a known gnd point (bracket that holds the boost/pressure sensor on the chassis). Then key to ON. Pump should run. IF it does, then the gnd for the afm and yellow check connector has gone south for unknown reasons (located on top of the rear rotor housing.....intake has to be removed to access this gnd pt).
This post is just a repeat in many ways of Scath above. Try 'em all....one at a time.
Or try this: Pull the small trigger wire off the starter. HOLD the key to START. Pump should run. This is an alternate way of pullking in the circuit opening relay. That relay has TWO coils that can pull in that relay. This method uses the coil that has not been mentioned in the above. Starter won't turn for obvious reasons.
If good.........then with meter on ohms, see if it is indeed going to ground.
That otta keep you busy for the next couple of hrs.
FYI: The MAIN RELAY has zip to do with the fuel pump coming on. It can be in the backyard in the dog house and the fuel pump will run with key ON, yellow jumper jumped or key HELD to Start the pump will run as long as the key is HELD to Start. The fuel pump running is about all that will run though. Engine won't start with main relay not pulled in.
ENGINE fuse provides power to the circuit opening relay and to the fuel pump via that relay. Engine fuse also powers the coil in the main relay. If the main relay pulls in then the ENGINE fuse has to be a good player.
I have the ability to repeat myself alllll daaaaay long.
07-09-10, 05:45 PM
#4
Hailers,
Thank you for the information. It sent me in the right direction and I found a cut off rocker switch that was put in for theft deterrent reasons. I got the car from the guys dad and he obviously did not know anything about it either! Gotta love this ****!
Whenn I was working on it my mind kept thinking about an alarm system!
LOL. Well it runs so now time to fix the coolant leak near the intake manifold.
Thank you for the information. It sent me in the right direction and I found a cut off rocker switch that was put in for theft deterrent reasons. I got the car from the guys dad and he obviously did not know anything about it either! Gotta love this ****!
Whenn I was working on it my mind kept thinking about an alarm system!
LOL. Well it runs so now time to fix the coolant leak near the intake manifold.
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