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General Site Info => General Discussion => Topic started by: Stewart G Griffin on February 15, 2020, 06:15:58 pm
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The first problem is that the car was sitting for at least 3.5 years and when i went to try to crank it this morning, the starter did kick for a second, but now we've lost ALL electrical power as if there's no battery. Battery is good though.
Previous to that about 2 years ago at least it would crank, but no fuel pump, which, now that i think about it, this may be related to above, but one step at a time.
NOTE: 1) i can provide pictures AND scan in anything from the service manual----i just don't quite know how to "read" the service manual/diagrams.
2) My electrical knowledge/ability is not that good, but i'm willing to learn.
90 cavalier 4 cyl.
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Clean your battery terminal connections.
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with vile like normal. single click then no more power sounds like either a loose connection that arced out and no longer has any connection or a poor connection that has arced out. since you have no power anywhere it kind of points directly to the battery
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Clean your battery terminal connections.
The professor of few words was right! When i first tried this yesterday morning it was in the garage and dark and i whipped the battery in there. So, i assumed the cables were clean. After thinking about it, i looked again WITH LIGHT and the cables were really bad--the car really hasn't been run since 2013! i cleaned the cables with baking soda, wire brush etc.
i have power and cranking now. But now we're are at the next step---which is where we were 3.5 years ago----NO FUEL PUMP. i should say, you may or may not know, when you turn the key towards start on a TBI car, you should hear the fuel pump for 2-3 secs. i don't have that and the engine won't start but will crank.
What to do next?
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well check all your fuses, cant really help you out with the setup as im not even sure about it. might also look to see if it has a fuel pump relay under the hood
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Yeah, the underdash fuse for the pump is good. i guess the next step is to test relay etc.
i did some reading in the service manual and discovered there is a test connector for the fuel pump for cars behind the driver's side strut tower. Not sure if trucks have this or not? i assume this bypasses the relay?
(https://i.imgur.com/13GpSfQ.jpg?1)
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our tbi trucks do have one. wasnt sure if your car did. but you should be able to apply B+ to it and even with the key off it should run the pump till you unplug it
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Did you check all of the fuses? My last 3+3 popped the ECM2 fuse fairly often, and it in turn doesn't power the fuel pump.
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Both ECM fuses checked out ok.
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what about the relay bypass?
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what about the relay bypass?
Couldn't get the pump to run that way, but i did do a test using that bypass from the service manual hooking the test light to B- turning the key on and the light went out after 2 secs.
i have to rush off to work as i'm on night shift this week, but there's much more to report----i think the fuel pump relay melted.
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if you applied B+ to the bypass and the pump didnt turn on the pump is either fried or the wire is broken going to the pump
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You need to run B+ directly to that pigtail which bypasses the relay and directly feeds power to the fuel pump. Hook it up securely and get under the car with a rubber mallet. Slap the tank a few times and listen for the pump to come on for a quick test.
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No pump after applying power direct to the pigtail.
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did you slap the tank with the B+ hooked up? this can make the pump jump and start up. if it does you know pretty much for sure the pump needs replaced. if it doesnt then you need to make sure the power is getting back to the pump if it is then you need to replace the pump.