I have an issue with my truck where it just shuts down. Either while I am driving or whatever. I usually can not get it started again for about 2 hours. After it seems to cool off some. I have put a new ecm and fuel pump. Changed out the distributor, new cap, rotor, wires, plugs, and ignition coil. I also changed out the map sensor on the throttle body. My truck will not start at all and has no spark. I am not getting any power at the ignition coil. I jumped out the ignition coil and I heard the fuel pump kick on but it still wouldnt start. Ive had the truck in and out of the shop and can not determine the cause of the shut down. Ive narrowed it down to the ignition system. Has anyone had a similar issue, if so how did you remedy it?

 

First, are there any codes? Does the fuel pump come on when you first turn the key? Is there power to the SMEC (computer) when it won't start?
The coil gets its power straight from the SMEC. It comes from pin 2-12 which is in the 14 pin connecter. This wire is 18 gauge black/gray in color. If you back probe the connector at the SMEC and still have no voltage the problem is in the SMEC or you may have corrosion in that pin. If there is power at the SMEC on pin 2-12 disconnect the positive wire at the coil and check for voltage on the wire. If there is no power it is a problem in the wire between the SMEC and the coil. If there is voltage it is a coil problem.

 

Sorry I didnt get back to you sooner. Thank you very much for responding. The truck is giving these codes: 12, 37, 33, 42, 11, 55. One of the codes is an AC code but I dont have AC. Another one is a torque converter lock out selonoid, and my parts guy said my truck doesnt have that in trans. When you first key up the fuel pump does come on. Before you had responded back I hooked my DVOM to positive side on the ignition coil. When id key up the voltage would go up to 11 or 12 volts and then drop down to a real low voltage but still no start. I had the key turned on and pulled the 14 pin connector on the ECM then plugged it back in, turned the key to start and the truck started. checked the wiring harness and all the wires seemed to be fine. Trucks been running up until today. I have been running the truck but not driving it. If im looking at the connector what pin would be 2-12?

 

That is the kind of info that helps trouble shooting. Code 42 (ASD relay circuit fault) is pertinent to the symptoms you describe and will cause the code 11. With those codes I would trouble shoot the ASD relay circuit and probably replace the ASD relay since it is an intermittent problem. The ASD relay should be the 2nd one from the front just under the drivers side hood spring.

With this new info I would not worry about the 14 pin connecter unless the ASD does not solve the problem. To answer your question though looking at the terminal side of the connector there are two rows of pins with a rounded end and a square end on each row. With the round ends to the left the upper left pin is #1, the upper right is #7, the lower right is #8, and the lower left is #14.

 

On pin 2-12 is it a constant power or only when the key is on? I backed probed the pin to see if there was power with the key on and off and its not getting any voltage. Also, I pulled the wiring harness out of the loom and traced the wires. I am wondering if pin 2-12 should go directly to the positive side or the negative side of the ignition coil? I followed pin 2-12, which is a black wire with a white stripe, its connected on the negative side of the ignition coil. On the positive side is a grey wire about a foot long which goes into three green wires with a black stripe. Two are 14 gauge wires: one goes to the ASD relay and the other to the fuel pump harness. The 18 gauge wire goes to the SMEC connector thats bolted in. They also split off and go to the passenger side of the engine and are all connected by a soldered joint. I am thinking the wires could possibly be crossed and that there are wires spliced in that should not be there.I was also wondering if there are any after market companies that you know of that sell the wiring harness for my vehicle? I have been looking and have not been able to find anyone.

 

I have an '88 dodge ram d100 with a 318 - takes 13 quarts to get the oil to "full" on the dip stick - since everyone answering here seems to have a 318, wonder if y'all could pop your hoods and verify a couple of things for me:

1. What is the part number on your dip stick?? Mine is 3870265 - stamped on the stick itself.

2. How long is your dip stick tube, measured obviously to where it enters the engine? I suspect mine may have been replaced?? Mine measures approximately 14 1/2 inches...

Sorry for reposting here, but this is driving me NUTS.....as I understand it, even with a large sump, this engine should only take about 7 quarts....5 qts with a standard sump (oil pan)....

thx, mike

 

mjm1988: The reason I hesitate to answer to your question is that you cannot tell us whether you have a stock oil pan. Only you can provide this info, without this info whatever info we give you may be wrong for your engine and cause a catastrophic failure of your engine. With that in mind here is my info.

I have a stock oil pan, dip stick and tube. My stock dipstick part # is 4483106. The length of my dip stick from the bottom of the dust cap to the full mark is 30 5/8 inches. My tube length is 14 1/2 inches sticking out of the block.

You must compare your oil pan with other 318 oil pans by sight to figure out if it is stock. I would suggest you take some measurements of your pan and go by a salvage yard to compare it to other 318s. While you are there you can take measurements on the dip stick tubes and check the part numbers on the dip sticks.

 

jflex79; As mechanics we must adjust our trouble shooting approach as we get new information that leads us in a different direction. A code 42 should take you to the ASD system. I would trouble shoot that system first. Any good manual will explain this procedure.

The power at pin 2-12 is key on. This can be effected by a fault in the ASD system.

My wiring diagram shows the wire from pin 2-12 going to the positive side of the coil. The gray wire is shown to go to the negative side of the coil. However on my truck they are (like yours) the opposite of what my diagram says and my truck runs fine. My wiring diagram also says my coil should be on the right side fender shield when it is actually on the fire wall so these things cause me to question the validity of my wiring diagram at this point.