Lesson Learned about paying attention to detail

[Fordman999]

Hello everyone so I thought I would post this just as an example of how a slight mistake has cost a lot of money and a lot of problems. So about 1 year ago I was having serious problems with my engine. My catalytic converter went bad and 02 sensors. I thought since my Explorer had 190,000 it was normal. After about $1200 later (and that was an aftermarket converter,( Ford wanted $2000 just for the converter) my car was still having issues. After changing my coolant sensor, MAF sensor, fuel filter, sparkplugs, intake manifold gaskets, new gas cap, checking all vacuum lines, new fuel sensor, new egr valve, my car was still having problems.

Finally I was sitting yesterday just looking at my engine trying to thing what the HELL could be the problem and guess what......I noticed the sparkplug wiring didn't look right. About 2 years ago I had changed by igintion block and I put the wires back in the same location since I marked them with marker but I had an apprentice mechanic do a tune up for me and DAMN HE MESSED UP THE ORDER WHICH THE SPARKPLUGS SHOULD GO. This has been the cause of all my headaches and yesterday I went online to see the firing order and wired it correctly. About 4 wires were wrong. Since then my car has been running fine and no more codes. Man how some miswired sparkplug wires can cause problems to the cat and engine and just something that could have been avoided with attention to detail.

Well guys point is make sure the firing order is correct. Mine was weird wiring 123465. There are diagrams online showing correct wiring depending on your vehicle.

 

[Turdle]

Don't feel bad, as this is one of the most common mistakes made by the DIY'er and the ford V6 DIS ignition.

There are several threads that end up like yours, even after it had been suggested to "triple check the firing order"

Glad you got it fixed.

 

[swshawaii]

+2. If only the 4.0 coil pack order was sequential 4-5-6. Surprised no mention of a blinking CEL or p0300 series misfire codes.

On board diagnostics (OBD-II) in the Maintenance and Specifications chapter.

If the light is blinking, engine misfire is occurring which could damage your catalytic converter. Drive in a moderate fashion (avoid heavy acceleration and deceleration) and have your vehicle serviced immediately.

Under engine misfire conditions, excessive exhaust temperatures could damage the catalytic converter, the fuel system, interior floor coverings or other vehicle components, possibly causing a fire.

http://www.fordservicecontent.com/Ford_Content/catalog/owner_guides/03expog5e.pdf (Page 11)

 

[Fordman999]

Yep and this is the diagram I used to wire it correctly.

 

[Fordman999]

Don't feel bad, as this is one of the most common mistakes made by the DIY'er and the ford V6 DIS ignition.

There are several threads that end up like yours, even after it had been suggested to "triple check the firing order"

Glad you got it fixed.

Thanks Turdle I feel better, felt a little bad about the whole thing.

 

[Fordman999]

+2. If only the 4.0 coil pack order was sequential 4-5-6. Surprised no mention of a blinking CEL or p0300 series misfire codes.

No swshawaii I did not get those codes you referenced and that is why it was so difficult to figure out. I only got P0172 & P0175 codes and that made it more difficult but luckily I noticed the sparkplug wires and looked a little closer