Ignition troublesooting HELP!
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
Ignition troublesooting HELP!
long story short, the car stopped running right then stopped running at all. Optispark was suspected, and was replaced.
and the same problem remains.
So I checked for spark again at the plug wires.(put a screwdriver in the plugwire end and held it near the ehxaust manifold) it cranked and cranked, sparked once and almost fired, then kept cranking, same as before.
so I checked the coil by the same method. hooked spark plug wire to coil post, then attemped to arc it on a ground. cranked the engine, and there was no fire.
disconnected the 4-prong connector at the coil, tested for voltage at the prongs... with the key in the "on" position" the only prong with power was the lower prong in the gray (passenger side) connector.
QUESTIONs-
are more prongs supposed to have power than the one that did?
Is that even a definitive way to test the coil function?
how can I eliminate the possibility of a failed coil?
what else could It be?
and the same problem remains.
So I checked for spark again at the plug wires.(put a screwdriver in the plugwire end and held it near the ehxaust manifold) it cranked and cranked, sparked once and almost fired, then kept cranking, same as before.
so I checked the coil by the same method. hooked spark plug wire to coil post, then attemped to arc it on a ground. cranked the engine, and there was no fire.
disconnected the 4-prong connector at the coil, tested for voltage at the prongs... with the key in the "on" position" the only prong with power was the lower prong in the gray (passenger side) connector.
QUESTIONs-
are more prongs supposed to have power than the one that did?
Is that even a definitive way to test the coil function?
how can I eliminate the possibility of a failed coil?
what else could It be?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
A good test of a spark coil is to pulse 12v to the primary with the secondary 1/2 inch from ground to see if there is any spark. Place a .05 mfd to 0.1 mfd capacitor across the primary wires. You should see a fat blue spark.
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
Bought a new coil. didn't help at all
took it back apart and now i have the ICM sitting in front of me.
can't get a new one till tuesday.
how do I test/repair this little thing?
took it back apart and now i have the ICM sitting in front of me.
can't get a new one till tuesday.
how do I test/repair this little thing?
Burning Brakes
Joined: Nov 2002
Posts: 1,239
Likes: 1
From: Las Vegas NV
Sound like a bad ICM. BTW keep the new coil, a bad coil can take an ICM with it. Here is how to test:
http://shbox.com/1/4th_gen_tech2.html#opti_test
http://shbox.com/1/4th_gen_tech2.html#opti_test
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
OK, put in the new ICM and coil and now I have a pretty good spark going, but the car still won't start
it cranks and fires up, runs for abour 3 revolutions and cuts out dead. try to start again, and same stuff. it won't run!
ANOTHER problem came up now too! The relay that has to do with the interior lighting. Every once in a while it'll just start clicking like crazy and turning the key off and all that dosn't help anything. So I pull the relay, the lights go out, then plug it back in and everything's good to go!
I'm getting a little discouraged here...
I am going to try replacing all the spark plugs and the O2 sensors next. I am runnin out of money, and ideas too!
it cranks and fires up, runs for abour 3 revolutions and cuts out dead. try to start again, and same stuff. it won't run!
ANOTHER problem came up now too! The relay that has to do with the interior lighting. Every once in a while it'll just start clicking like crazy and turning the key off and all that dosn't help anything. So I pull the relay, the lights go out, then plug it back in and everything's good to go!
I'm getting a little discouraged here...
I am going to try replacing all the spark plugs and the O2 sensors next. I am runnin out of money, and ideas too!
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
ANOTHER wierd thing. when I turn the key to the ON position and the dash lights up, the MPG numbers blink SYS three times and go back to "0mpg" for 15 seconds then blink SYS 3 times....and repeats
and when the relay clicks, it sucks the battery dry in SECONDS
somthing seems to be shorting out and causing the relay to spaz out and it is draining the battery. no fusus have blown though, so what is the freakin deal here!
and when the relay clicks, it sucks the battery dry in SECONDS
somthing seems to be shorting out and causing the relay to spaz out and it is draining the battery. no fusus have blown though, so what is the freakin deal here!
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Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
the battery has been drained out so many times now that I think it won't ever be right again, but it's on jumper cable to another car right now and it's been charging.
SO everything is put back together and it still won't start.
It's pulling air really well
it has good compression across the cylinders
the plugs , wires, opti, coil, and ICM are all new
It gets good spark all the way down to the electrode tips
It has 43# of fuel pressure in the fuel rail
the injectors click when it turns over
the spark plugs are firing in the correct order
It has plenty of quality fuel
When I crank it, it will hit sporadicaly, almost run, and go back to turning over like there is no spark.
it seems to come closer to running the longer I let it sit between attempts
ANYONE HAVE AN IDEA?!?!?
SO everything is put back together and it still won't start.
It's pulling air really well
it has good compression across the cylinders
the plugs , wires, opti, coil, and ICM are all new
It gets good spark all the way down to the electrode tips
It has 43# of fuel pressure in the fuel rail
the injectors click when it turns over
the spark plugs are firing in the correct order
It has plenty of quality fuel
When I crank it, it will hit sporadicaly, almost run, and go back to turning over like there is no spark.
it seems to come closer to running the longer I let it sit between attempts
ANYONE HAVE AN IDEA?!?!?
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
Originally Posted by crheinish
First check for DTCs. Second install a new battery. Third you may have the wrong ICM, they are year specific.
oh great! year specific...that throws a whole new thing into the mix.
but I'm getting spark, in the correct order. ... .. So what would year differences have to do with it?
0h...what is a DTC?
Thread Starter
Racer
Joined: Apr 2004
Posts: 298
Likes: 1
From: Springfield Missouri
Originally Posted by crheinish
First check for DTCs. Second install a new battery. Third you may have the wrong ICM, they are year specific.
and what are DTCs?
Burning Brakes
Joined: Nov 2002
Posts: 1,239
Likes: 1
From: Las Vegas NV