My truck wont start, I pulled the motor out and OH it, no electrical changes were performed, engine was running fine.

After several weeks chasing my tail, I found that I have a cold/weak spark, out of the coil but not spark to the plugs. I replaced the coil with a new MSD 8228 coil and still have the same problem.

1. From the coil, + DG/OR to ground the multimeter beeps continuity.
2. From the coil, - BK/GY to ground the multimeter beeps continuity.
3. Multimeter to +/- on coil reads 0v switch on/start.
4. Multimeter to + DG/OR on coil reads 12v switch on one sec. then 0v and 9v at start.
5. Multimeter to -Bk/GY on coil reads 12v switch on one sec.then 0v and 0v at start.

It seems to me that the + DG/OR wire is grounding out somewhere. I unplugged all the connections from the PCU and sensors, still multimeter beeps ground. I unplugged a grounding wire that goes to the A/C pump and the continuity beep stops. Im confused!

 

Has it rained heavy lately?

 

Yes, but my truck has been covered. Why?

 

O ok, well if your weather stripping is missing under your hood, water can leak into the bay and get onto the distributor and cap and what not, causing malfunctions.

 

Dunno what to tell ya man, chasing a short, especially one that could be in several places--as in your case, is probably #3 on my things I don't want to happen list. Right after being shot in the dick and having it bitten off.

Chase the wire to origin, and figger out where your voltage starts to drop.

 

Well it is not the coil, crank position sensor and pick up coil. My next step is to replace the PCM.

 

Flash it maybe, Cheaper.

 

Flash is $350. Salvage is $150.

 

Not to mention that flashing it wouldn't fix your problem. If the PCM is what is causing this, it is due to an internal fault that a flash wouldn't fix.

That being said, when you swap PCM's, you have to get the new one flashed to your VIN anyway. Where did you come up with $350 for a flash? Got mine done for $70. Try calling a different dealership and getting a quote.

 

I had my PCM flashed in mid 2006 by B&G Performance for $350.00 and they are still charging the same. I have checked all the wiring, connectors and sensors and I continue to have the same problem, no start and a cold(weak) spark. My assumption is the PCM is not functioning properly.

Im considering buying a PCM from the salvage for $125.00, if that solves the problem then I will send the PCM to get flash. Mad_Scientist, where did you get your PCM flashed for $70.00?