Code 18

nitrouspaul

Registered User
I have been chasing a misfire problem for 3 weeks now and the time is desperate as I have a 2000 mile return trip ahead of me starting tommorow nite. That leaves me all day tommorow to finalize a solution to this problem

Here is a brief history.

Surging, knocking etc.When you try to give her a little gas she revolts with a misfire almost as if the charge is being lit off when the piston is coming up on compression.

Changed cam sensor. No Joy. Changed plugs and wires. Motorcraft an autolite double plats. No Joy. In fact a little worse after plugs and wires.Also removed saw connector. No Joy.
Running codes.

Get code 18
loss of tach signal to electronic control assembly\
or
Dis Fault
primary curcuit failure in coil1,2,3,4,
or
electronic distributorless ignition system (EDIS) fault
failure in spark angle word circuit.

Also getting code 77 and 74brake on off switch don't care about that one and operator error during self run test. this is a new one.

Problem is I ran the test numerous times and cleared the codes once.
I am still having the stumble and miss problem with yet to try a new coil.Ther is lots of spark and I tested the resistance acrooss the banks in the coil
All are 14.5 ohm and consistent.

What gives here??
Any ideas out there?

I don't want to believe it is a coil since it is a relatively simple part with few failures.
I have tried a second DIS I got from a 90 cougar xr7 and also tried the tests and driveing with the in line spout saw connector dis connected to try and get to base timing. no Joy here either.and same codes.


I have to drive this thing sputtering for 2000 miles tommorow nite.
I also checked the crank trigger and there is a little oil from a front seal leak in and on it. Dont know if this will do anything or not and checked the balancer bolt all O.K.


Any one care to try a suggestion here. I shall be on yahoo messenger for the rest of the nite if you wish to reply in a faster method and are also signed up there. My handle is nitrouspaul@yahoo.com

Thanks to all in advance.
God bless America and George W.
 
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What did you measure on the primary side of the coil? There are 4 wires one is B+ the others are coil 1,2 and 3. Measure between B+ and any one of the other connections. They should also be the same. I don’t remember the wire colors right now, but it’s pretty easy to figure out. I think it’s a red wire w/stripe for B+ and the others are tan with a colored stripe.

You might also have a bad connection or frayed wires somewhere.

Jeff
 
if there is a bad wire somewhere where is the most likely place. From the crank trigger or into the dis or into the coil.
 
If your coil circuit resistance checks are essentialy equal, then the thing left is your DIS. When you see ths "coil circuit x failure" 9 out of 10 times its the DIS itself. OK... just to help you out here... Cam sensor, crank sensor, plugs, plug wires, and EEC cannot cause that code. Only the coil pack itself, and the DIS.

Mine went out earlier this year, symptoms were an abrupt drop in power (and tach speed), ran OK for a few minutes when first started up and the engine was cold, occasional, almost imperceptible drop-out/misfire.

Hope this helps.:D
 
Have you checked/ changed the crank sensor? I believe they run about $25 at most parts stores. Also check the Harmonic balancer. It has the ring for the sensor on it. Mine broke, car would start but would not accept any throttle-just like yours. Missing, popping through the intake, etc....The balancer had broken in half, the ring was not spinning at the same speed as the rest of the balancer causing ignition timing to be way off. Just a thought.
 
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