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senor honda
12-21-2010, 07:00 PM
89 Accord has had a MSD Blaster coil in place of the stock coil since January 2010. This car was running last week when I took out the transmission for rebuilding and put it back in. This morning, I adjusted my valves.....try to start the car, no spark at the coil wire, when held 1/16 " from the block, key on, starter turns motor over.

Problem: No spark at the coil wire.

It is wired as follows....
From Factory wiring harness.....big black/yellow sends 12volts to positive side of MSD coil. From positive side of MSD coil a small black/yellow sends 12 volts into the Hitachi distributor.

From negative side of MSD coil, two wires:
Wire 1 is a small blue wire that sends 12 volts back into the factory harness....probably sends a signal to the tach or to activate the fuel pump. Wire 2 is a small blue wire that sends 12 volts into the Hitachi distributor. When 12 volts go to the positive side of the MSD coil, both wires on the negative side also have 12 volts.

3rd wire from factory harness is a small black/yellow wire that goes into a condersor......labelled as "136 A 250-0.47". and comes out a small black wire that is grounded to the distributor body. When 12 volts is on the positive side of the coil, the wire going into the condensor has 12 volts...the black wire
coming out the condensor that is grounded to the distributor body has nothing. I tried swapping condensors....it still tests 12 volts coming in, nothing coming out the small black wire. PLugs on the condensor are male/female so they cannot be plugged in backwards.

This car was running last week when I took out the transmission for rebuilding and put it back in. This morning, I adjusted my valves.....try to start the car, no spark at the coil wire, when held 1/16 " from the block. Key is on, starter turns motor over. It won't even backfire. It won't crank/run on starter fluid.

I did a continuity test and the coil wire conducts electricity. . How can there be 12 volts coming into the positive side of the coil and
out the negative side with no spark being generated out the coil wire?

Any ideas?
Thanks in advance.-Bob

Dr_Snooz
12-21-2010, 09:25 PM
If the coil is bad, it would cause that. Here is a link (http://wiki.answers.com/Q/How_do_you_test_an_ignition_coil) describing a test. It gives average resistance numbers for all coils. You should really get the exact resistance numbers from MSD though. If you don't have a multimeter, buy one. It's cheaper than a new coil.

Let us know what you learn.

senor honda
01-21-2011, 02:42 PM
What I learned....
There is an ignitor within the non-injected distributor.
There are 90 degree electrical slip-on connectors to the ignitor.
A 20 year old car has cracked wires sometimes as they enter the distributor.
If those wires short out to the dizzy body it might kill the ignitor.

My solution....
New $179 distrib came with new ignitor and new vac advance.....tested with meter......ignitor was good...........old ignitor was dead. New distrib came without cap/rotor/wires and without a seal where the wires go through the distrib body.......grrr... went to Home Depot and bought a box of 90 degree slip on e-conns......put two on with new wiring, squeezed them before sliding onto the ignitor....

Made an aluminum cover complete with new grommet and slipped it over
the wiring that I just made, and epoxied it in place to seal against water.
Put "Goop" on the two e-conns to keep them glued together as one plug.

....still working on a solution for the vacuum advance, since the new vac-adv
on the new distrib doesn't allow full rotation/full advance for setting the timing.....groan...

Still tuning, but plugs are very light tan and the last two fillups say 19.1 mpg.

I have a carburetor....for 1990/Car and Driver magazine...the car got 22-24.....probably an EPA estimate....What true/calculated mileage is everyone else getting? -Bob

lostforawhile
01-21-2011, 02:47 PM
These igniters burn out with the stock coil, I don't like the idea of running an aftermarket coil with the stock one, now if you have a box, it just acts as a signal and removes all load from the unit.

Dr_Snooz
01-21-2011, 08:46 PM
I'm getting 32 mpg consistently.

MessyHonda
01-22-2011, 12:13 AM
I'm getting 32 mpg consistently.

damn you...im lucky to get 22mpg...I need to get it tuned soon

senor honda
01-22-2011, 07:24 AM
I'm getting 32 mpg consistently.

Then how about telling us what you have your tuning specs set to.
and anything else that might help us increase gas mileage?

EPA (calculated) (guesses) gas mileage estimates are usually higher than real life.

My engine is a new A20 with a carburetor.
Thanks.-Bob

Dr_Snooz
01-22-2011, 08:23 AM
Then how about telling us what you have your tuning specs set to.
and anything else that might help us increase gas mileage?

EPA (calculated) (guesses) gas mileage estimates are usually higher than real life.

My engine is a new A20 with a carburetor.
Thanks.-Bob

I'm bone stock. You have some mods (MSD box), so you can round down accordingly, but 19 MPG seems pretty low for a carb. I know that the stock A20 carb cars get somewhere around 37-40 MPG pretty consistently. Unless you have a supercharger or something, I would think you'd be getting a lot better. Messy has crazy mods and is getting better mileage than you are. Does your exhaust smell rich? Does the car smell like gas when sitting? Are you experiencing any running issues (black smoke, poor performance, etc.)? Without knowing more about the car, it's hard to say what's wrong.