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Still don't know how to jumper something

  • Thread starter Thread starter im2damncool
  • Start date Start date Mar 28, 2008
I

im2damncool

Founding Member
Dec 28, 1999
249
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0
Chico, CA
Mar 28, 2008
#1
  • Mar 28, 2008
  • #1
I'm just trying to find out if I have spark. How do I jumper the starter solenoid and what is that supposed to do? My car won't start so I want to see if I have fuel and spark first. I just don't know how to tell for either one... BTW I am working alone so I can't have a helper crank the car while I watch.
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Mar 28, 2008
#2
  • Mar 28, 2008
  • #2
basically jumper is either connecting a jumper wire ( a wire with alligator clips on either side) to each side of a terminal, or for the starter, when you look at it, the two bolts sticking out on the starter relay (starter solenoid). One of them connects to the battery and the other the starter. You can also "jumper it" by using an insulated screwdriver and when holding the plastic/rubber/etc handle, place the metal end of the screwdriver so it hits both of the bolts sticking out or the starter relay.

By jumping the starter relay it sends the current directly to the starter so it will crank from outside the car.

To test for fuel I guess I would see if when you push in the shrader valve (same as which comes on the tire), which is located behind the alternator, located on the fuel lines which go to the fuel rail. Make sure you have a rag handy when you push it in with a screwdriver, as fuel may shoot out. But ultimately the best way would be to get a fuel pressure gauge and hook it to the shrader valve in order to measure the pressure once you turn the key to the key on/ignition off position.

Or just checking the spark plugs to see if they are covered in gas I guess too. Any thing else escapes me for the moment, as sometimes the most obvious things don't come to mind.
 
I

im2damncool

Founding Member
Dec 28, 1999
249
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0
Chico, CA
Mar 28, 2008
#3
  • Mar 28, 2008
  • #3
now the starter relay seems to have three things coming off it. The two bolts you mentioned and a push on connector which when removed is just a metal spur. Does that piece need anything done to it. Also, does this tell me if I definately have spark going to the engine? Also how do I know if I'm getting fuel to the injectors?
p.s. That was the best answer I've gotten so thank you

Thanks again. I'm going out to the garage right now.
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Mar 28, 2008
#4
  • Mar 28, 2008
  • #4
ignore the push on connector for now, to check if the injector is working you can stick like a pushpin into the wires in the injector, one to the ground and one to the power wire, then put a test light to it when you try to start it to see if the injector is pulsing like it is supposed to. the light should come on and off sporatically.

By jumping the starter relay you are getting power to the starter, so you should hear it crank. I may be mistaken but u should have the key to the on position when you do this also and it will attempt to start the engine, basically you are bypassing the relay which is put into action when you turn the ignition to start the car.

One thing that has always helped me diagnose problems is the cranks ok but no start checklist, which you can find via a search on the forums. there is tons of info there.

Hopefully someone else can chime in with more ideas for ya, I'm drawing a blank while i'm at work, but maybe when I get home to my car I'll come up withsomething else.
 
I

im2damncool

Founding Member
Dec 28, 1999
249
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0
Chico, CA
Mar 28, 2008
#5
  • Mar 28, 2008
  • #5
3 weeks later, and I got it. I had to tape a nail to a screwdriver to reach the two contacts on the solenoid but I did get spark there. And I got fuel spraying out of the schrader valve. So I'm pretty sure I'm getting fuel to the engine. I tried the screwdriver in the end of a plug wire trick(in a dark garage so I would be able to see it) but the battery didn't have enough juice to turn over. Once it's charged and I try it again, if I do get a spark from the plug wire what should I check next? Car turns over but won't start.

Before it died it would lack power sometimes till then suddenly it would accelerate normally. Also the check engine light would come on every time I accelerated onto the freeway, then go off after a few seconds. I tried to pull codes the other day but it only makes 2 quick clicks then won't do anything else, and I don't get ANY codes at all.
 

capri debris

Member
May 5, 2007
289
6
18
PA
Mar 28, 2008
#6
  • Mar 28, 2008
  • #6
Checking power to the starter and checking for spark are two different things.

Jumping the relay will only tell you that power is getting to the starter if it cranks the engine over.

That will not tell you if you have spark (power to the spark plugs)

To test that you need to pull one of the plug wires off and put a screw driver into the boot of the wire and make sure it's contacting the metal clip inside it.

Then place the metal part of the screwdriver near the frame and have someone crank the engine... if you see a spark jump from the screwdriver to the frame, then you have spark.
 
I

im2damncool

Founding Member
Dec 28, 1999
249
0
0
Chico, CA
Mar 28, 2008
#7
  • Mar 28, 2008
  • #7
Once I get the battery charged back up, I'll try that. If I do get spark at the plugs, what do I check next? Do the symptoms help to diagnose the problem?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 28, 2008
#8
  • Mar 28, 2008
  • #8
It sounds like you did not get a spark tester. For one man spark testing, you might want to connect a wire to the threads of a spare spark plug. Now connect the other end of the wire to ground. Alligator clips can help with this. This is kind of a poor-man's spark tester. I like to close the plug gap up on a 'tester' like this (to about 0.035" initially. I later open it back up and retest).

Now connect a plug wire to the spark plug and crank the engine. Watch the plug and see if spark jumps it's gap. The fact that you have a ground wire on the plug means you can normally put it someplace where you can see it. If not, a telescoping mirror can help you see around the hood from the driver's seat.

Good luck.
 
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