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I don't know much about electricity. let me just begin by getting that right out in the open. I've fumbled my way threw a few problems already with a multimeter i picked up awhile back.

 

I've been troubleshooting a loyale, ea82 spfi that won't start after putting in a rebuilt engine. some might recognize my plight from the other threads on the topic.

 

I've got spark. I don't have gas though, and I'm not sure why. When I turn the key to the on position, I don't hear the hum of the fuel pump. When I crank it, my meter reads 8.8-9.0 Volts. Is this what should be going to the pump? I was thinking it should be 12. What could cause this?

 

belizeanbus

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I don't know much about electricity. let me just begin by getting that right out in the open. I've fumbled my way threw a few problems already with a multimeter i picked up awhile back.

 

I've been troubleshooting a loyale, ea82 spfi that won't start after putting in a rebuilt engine. some might recognize my plight from the other threads on the topic.

 

I've got spark. I don't have gas though, and I'm not sure why. When I turn the key to the on position, I don't hear the hum of the fuel pump. When I crank it, my meter reads 8.8-9.0 Volts. Is this what should be going to the pump? I was thinking it should be 12. What could cause this?

 

belizeanbus

 

The 8-9 volts is measured where?

What is your voltage at he battery while cranking. If there is a 1 volt difference thats acceptable.

Is there power at the fuel pump, if not replace the relay.

 

 

nipper

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The reason the voltage is low is because the load the starter motor puts on the battery. If you check the voltage while not cranking it will measure higher.

 

The fuel pump circuit has a relay in the circuit that passes power to the pump. It seems you are getting voltage to the pump though. The problem may be with the injector not opening and so pressure is not dropping to allow the pump to turn on. Try placing a test light tied to circuit by placing the clip lead to ground and the probe end to each side of the injector wires. One side should be always be lit and the other side should pulse on and off with the injector while cranking the engine. If the light is always on then the injector is not getting the pulses to open it.

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Thanks for the advice. I tested the resistance on the injector and it is within the bounds set out by the manual. I then tested the other end with a test light, and it does not light up on either of the two sides (ports, leads, wires, I don't know what you call them) when cranking the engine... so I gess this means that there is no power getting to the injector. The wire goes into a great big wire harness... from there I don't know where it goes. All fuses under the dash are good.

 

Any other thoughts...?

 

belizeanbus

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the two non-starts i couldnt' figure out both ended up being distributors that tested fine (the crank angle sensor resides inside of the disty). both times was immediately following an engine install as well....i don't know for sure, but assume that corrosion builds in the disty's crank angle sensor while not in use during the down time for the engine install. happened twice in 3 years. i would try anothe disty...but i've had bad luck with them.

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the two non-starts i couldnt' figure out both ended up being distributors that tested fine (the crank angle sensor resides inside of the disty). both times was immediately following an engine install as well....i don't know for sure, but assume that corrosion builds in the disty's crank angle sensor while not in use during the down time for the engine install. happened twice in 3 years. i would try anothe disty...but i've had bad luck with them.

 

Did you replace the entire distributor, or just the rotor? Disty's are pricey!!!

 

belizeanbus

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No voltage to the injector you say. Lets go hunting then, armed with your trusty voltmeter. (We won't need the Colt .45 yet)

 

First, check to make sure that the green fusible link is ok. This is located in the box mounted on the coolant reservoir. Make sure there isn't a loose connection there and that voltage is getting to both sides of the link with reference to ground. If that is ok then we need to check that voltage is getting to the ECM. Power is supplied to the ECM via the ignition relay and go to pins 29, 41, and 49. Make sure there is voltage getting to those pins with the ignition switch 'ON'. If those pins measure ok then the ECM may be the trouble.

 

The injector leads go to pins 43 & 48 of the ECM by the way. You should be able see the resistance of the injector across those pins. Be sure power is off and remove the connector from the ECM before you measure it just to be safe, if you do that. This will verify there isn't a break in the wiring to the injector.

 

Thanks for the advice. I tested the resistance on the injector and it is within the bounds set out by the manual. I then tested the other end with a test light, and it does not light up on either of the two sides (ports, leads, wires, I don't know what you call them) when cranking the engine... so I gess this means that there is no power getting to the injector. The wire goes into a great big wire harness... from there I don't know where it goes. All fuses under the dash are good.

 

Any other thoughts...?

 

belizeanbus

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maybe I'm on to something here.

 

There are 2 green fusible links in the box attached to the coolant reservoir. I tested them with a voltmeter and got some strange numbers that do not mean much to me... here goes: On the front one, with the ground from voltmeter touching metal, I get 7V and 6V respectively off the two posts. When I measure between the two posts I get 7.8. The back one (closest to driver), I get 5 and 4 (roughly), when ground, and when measuring between it shoots up to 122.

 

That doesn't mean much to me, but in the process I saw a sign of life... when the key is in the on position (not cranking), there is no clicking from the injector. However, if I disconnect the front green fusible link, it begins to click. Disconnecting the second does not have the same effect.

 

Does this mean anything to anyone???

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disconnect the fusable links and take volt readings from both sides of them. one side should be 12 volts, the other should be zero. Techincally if thats 122 volts its impossible. if its 12.2 volts thats ok. i am assuming these readings are with the car off?

 

Dissconnect the altenator and check again. Same for the starter then check.

DO you have a problem with the battery dying?

i wonder if you have something that is shorting out .. or starting to go. You may want to try this again by yanking out all the fuses in the car, checking readings, then installling one fuse, check,then remove the fuse, and so forth.

 

 

nipper

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Okay... rechecked the fusable links... this time I get twelve volts on both of them, but the other side is not zero... more like 3. This is with the key off. Does this mean anything???

 

Further, is there a way to check the disty in relation to the injector...? Spark is fine, and as I said, I connected a test light to the wire harness that connects directly to the injector but got no light from either post while cranking the engine...

 

The car never had a problem before the rebuild (aside from gushing out oil). Never a dead battery...nothing. It still turns over fine, so it seems that the alt and the starter must be okay...? But something is certainly wrong. It'll run briefly if I pour fuel in the injector (for about 3 seconds...)

Thanks for all the time and thoughts... you all have helped immensely on numerous occasions...!

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The readings you gave are low. This means either the battery voltage is low (check the voltage across the battery posts) or you have a bad ground connection to the meter or from the battery to the car chassis. I assume the 122 reading was .122 volts since you were reading across the link and that would be normal if the link is good.

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You stated that you have 12 volts on one side of the links. If the links are good then you should see the same voltage on the other side. This is just a piece of wire basically. Any links that don't show the same voltage on the other side when connected normally are open and need to be replaced.

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