86 5.0 HO No spark after the coil

codybear · 09-07-2003, 01:43 PM

86, 5.0HO, no spark after the coil
1st off like to say great web site I have been reading for the past few hours... Heres the problem

I drove my car to work which is 2 blocks, get out go into work, about 15 minutes later I need to run home for something, car will not start, no juice comeing ot of the coil.. so I replace that, same deal..changed out the ECM, Cap and Rotor... I even a borrowed a distibutor from the local Napa..... no dice, I also noticed before I changed anything that there was no juice going to the fuel pump.... heres the question can a relay or switch cause the engine not to fire?? so anyhoo we ran a ignition power wire to the pump and now it comes on, but still have no spark@!

Thanx in advance for any help someone can give me

HotRoddin · 09-07-2003, 05:53 PM

Quote:

Originally posted by codybear
heres the question can a relay or switch cause the engine not to fire??

Sure it can, if you have no power goin in, then you ain't gonna have no power goin out. If you had no power making it to your fuel pump, then its entirely possible you have no power making it to the ignition module. I'd get a wiring diagram and start following the fuel pump power back to its source ... do the same thing with the ignition module and most likely somewhere along the line they are gonna share a common power source. Once you find that you should be able to find where you're losin the power.

codybear · 09-07-2003, 06:00 PM

Thanx I wasn't sure if a relay or switch could cause the coil/icm/dis. not to spark! I guess since we bypassed the fuel relay and the inertia switch (which also had no juice coming into it) that it wouldn't do any good except make the fuel pump run. is there a way to test relays?

PKRWUD · 09-07-2003, 06:45 PM

I suspect it's your ignition switch.

Try this:

Check the voltage at the red/green wire at the coil with the key on. If the voltage is less than 2vdc, hook up the fuel pump the way you did to get it to run. Get a jumper wire, and run it between the positive battery post on the starter relay, and the coil positive terminal (red/green wire). Now try and start it.

If it starts, replace the ignition switch.

Take care,
~Chris

codybear · 09-07-2003, 07:04 PM

Thanx I will give that a shot also.... would that also kill the power to the fuel pump?

HotRoddin · 09-07-2003, 08:30 PM

Quote:

Originally posted by codybear
is there a way to test relays?

If you know what pins go where, and i think they usually have a little diagram on the side of them ??
Check for continuity on the energizer coil ... .check for power at the proper time to the energizer coil. If the relay is being energized, then make sure the signal or voltage level going in, is making it back out ... remember the relay is just like a toggle switch thats being flipped by the energizer coil instead of your finger. So you have two things to check ... the energizer coil (the thing that flips it on and off) and the switch itself (which is just some contacts that if closed let the signal pass and if open stop the signal at the switch).
This is one of those things where the concept is simple, but its difficult and complicated to explain

http://www.members.tripod.com/thefalconman4/relay.html

HotRoddin · 09-07-2003, 08:35 PM

crymany .... It's really simple when you know what your supposed to be looking for .... forget everything i just said and do what Chris said

PS: Plus he just told you how to hotwire a car

PKRWUD · 09-08-2003, 02:29 AM

I don't have a schematic handy at the moment, believe it or not, but to the best of my knowledge, the only place the ignition power primary coil wire and the fuel pump power wire come together are in the ignition switch. I'm not aware of any single relay that controls both.

codybear · 09-08-2003, 06:01 AM

Ok so the relay is bad and the hot wire trick didn't work.

don't know whats next?

yoshi351w · 09-08-2003, 05:19 PM

I agree with the ignition switch gone bad

codybear · 09-09-2003, 07:31 AM

Newest update... it is not the relay, out of the 4 wires going to the relay there is suppose to be 2 hot leads and there is only 1, so I will assume the one that isn't hot(but should be) is the one from the ignition? but if that was the case then it should have started on the hot wire trick right?

PKRWUD · 09-09-2003, 01:32 PM

If the "hot wire trick" didn't work, but you did have fuel, then the coil has to be bad. Try it again, but this time pull the coil wire that goes into the distributor cap out, and set it on the engine, near metal. Observe the wire while someone else cranks it, and look for spark.

codybear · 09-09-2003, 02:31 PM

*********UPDATE UPDATE UPDATE *************

it was the EEC relay! thank god it is over! Thanx everyone who particapated!

09-07-2003, 01:43 PM	#1
codybear Registered Member Join Date: Sep 2003 Posts: 63	86 5.0 HO No spark after the coil 86, 5.0HO, no spark after the coil 1st off like to say great web site I have been reading for the past few hours... Heres the problem I drove my car to work which is 2 blocks, get out go into work, about 15 minutes later I need to run home for something, car will not start, no juice comeing ot of the coil.. so I replace that, same deal..changed out the ECM, Cap and Rotor... I even a borrowed a distibutor from the local Napa..... no dice, I also noticed before I changed anything that there was no juice going to the fuel pump.... heres the question can a relay or switch cause the engine not to fire?? so anyhoo we ran a ignition power wire to the pump and now it comes on, but still have no spark@! Thanx in advance for any help someone can give me

09-07-2003, 06:45 PM	#4
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	I suspect it's your ignition switch. Try this: Check the voltage at the red/green wire at the coil with the key on. If the voltage is less than 2vdc, hook up the fuel pump the way you did to get it to run. Get a jumper wire, and run it between the positive battery post on the starter relay, and the coil positive terminal (red/green wire). Now try and start it. If it starts, replace the ignition switch. Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

09-08-2003, 02:29 AM	#8
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	I don't have a schematic handy at the moment, believe it or not, but to the best of my knowledge, the only place the ignition power primary coil wire and the fuel pump power wire come together are in the ignition switch. I'm not aware of any single relay that controls both. __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

09-08-2003, 05:19 PM	#10
yoshi351w Registered Member Join Date: Aug 2003 Location: s. fl Posts: 23	I agree with the ignition switch gone bad __________________ 351w powered 86 gt with a reverse manual c4. Lots more but whos counting.

09-09-2003, 01:32 PM	#12
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	If the "hot wire trick" didn't work, but you did have fuel, then the coil has to be bad. Try it again, but this time pull the coil wire that goes into the distributor cap out, and set it on the engine, near metal. Observe the wire while someone else cranks it, and look for spark. __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

09-07-2003, 06:00 PM	#3
codybear Registered Member Join Date: Sep 2003 Posts: 63	Thanx I wasn't sure if a relay or switch could cause the coil/icm/dis. not to spark! I guess since we bypassed the fuel relay and the inertia switch (which also had no juice coming into it) that it wouldn't do any good except make the fuel pump run. is there a way to test relays?

09-07-2003, 07:04 PM	#5
codybear Registered Member Join Date: Sep 2003 Posts: 63	Thanx I will give that a shot also.... would that also kill the power to the fuel pump?

09-07-2003, 08:35 PM	#7
HotRoddin cranky old man Join Date: Sep 2001 Location: Longview Texas Posts: 683	crymany .... It's really simple when you know what your supposed to be looking for .... forget everything i just said and do what Chris said PS: Plus he just told you how to hotwire a car

09-08-2003, 06:01 AM	#9
codybear Registered Member Join Date: Sep 2003 Posts: 63	Ok so the relay is bad and the hot wire trick didn't work. don't know whats next?

09-09-2003, 07:31 AM	#11
codybear Registered Member Join Date: Sep 2003 Posts: 63	Newest update... it is not the relay, out of the 4 wires going to the relay there is suppose to be 2 hot leads and there is only 1, so I will assume the one that isn't hot(but should be) is the one from the ignition? but if that was the case then it should have started on the hot wire trick right?

09-09-2003, 02:31 PM	#13
codybear Registered Member Join Date: Sep 2003 Posts: 63	*******UPDATE UPDATE UPDATE *********** it was the EEC relay! thank god it is over! Thanx everyone who particapated!

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