Hey folks,

Yesterday when working on replacing the thermostat in my 2000 Ranger, I noticed an electrical smell. Using the nose, I was thinking that it was either the alternator or one of the distributor caps. I was leaning towards the caps since a new alternator was installed a little over two months ago and the smell seemed to be coming from the caps more so than the alternator. That said, the fan was moving things around so I could be mistaken. Doing a Search here, I found a couple items that seem to be primarily at the root of this phenomenon, but mainly the alternator. While trying to diagnose another root cause for the failure of the heater control system (only blows in Defrost, the default setting by Ford for these failures), I noticed a melted line (red) just below the alternator. I'll be looking at this closer today to see if I can identify where this line runs (was getting dark). The reason I mention this is because after reading the threads here last night, I was thinking maybe the new alternator is running hot an was possibly behind the melt through on the vacuum line. So here are my questions for the group -

1. Has anyone experienced the electrical smell after the replacement of the battery and alternator? No smell makes it into the cabin, so this might have been before, during and after the replacement. And, probably not the blower motor going either. Also the alternator is new, not rebuilt.
2. Does anyone know what the vacuum lines (two red and one green vacuum line) support? The single red line pointed towards the rear of the vehicle is the one melted through. Intially I thought the Ford tech might have used a torch for removal of the old one, or something like that, and kissed the line with the flame.

Lots of good input at this site, so I'm hopeful I can tap into the expertise here. Thanks in advance!

Kevin

 

Check the electrical wires from alternator to see if any are too close to engine block/exhaust and insulation is burned through/shorting to ground due to sloppy install of new alternator. Might want to get a free electrical system test at advance or autozone to make sure charging system is working properly even though alternator was replaced. If any problems found head back to ford and make em fix it.

 

Thanks for the input. I was thinking the same re:installation. I have sunlight now, so I'm going to have a closer look.

 

OK - so I had the sunlight in my favor this afternoon and I was able to determine that one of my vacuum lines melted through due to contact with the exhaust manifold. The red line out appears to be the return (perhaps) to the canister. I think that this was collateral damage when the Ford tech replaced the alternator. I was able to splice the lines temporarily and now the heater control **** works in all positions. I'll see if the dealership is willing to give me a complementary line now that I did the trouble shooting.

OK, that's taken care of, but I do still smell the electrical odor. My best guess is that this is coming from the distributor caps (one or both). Straight off the top. I can see some browning of the plug wires, but its slight and confined to the area just outside of the boot. No electrical discharge that I can tell (I felt around the tops of the plugs; no 'bites'). 92K on the truck, so I'm getting close to plugs and wires. Could it be that??

Thanks.

 

Sometimes when something melts on exhaust manifold there is some residue left that needs to burn off. Assume by distributor caps you are referring to ignition coils, Never heard of them giving off a burning odor. Possibly there may be some arcing going on the wires. Might want to check to see if something fell on top of intake manifold and is getting cooked. Check the wire connections to the coils to see if they are too close to manifold since you can smell it in that region.

 

Maz,

Yes, you were right. When I traced the vacuum tube trying to locate the other half, I found it near the exhaust manifold. And on that, there was/is some residue. I picked off the larger portions of the plastic, but there is some there that remains as a witness mark. I plan to point that out to the service folks on my next visit (this coming Saturday).

Coils: yes, they certainly look like coils more than distributor caps. I took the truck for a short ride this evening, and when I got back, I popped the hood. A wiff of the electrical smell, but it dissipated quickly. I had to get over the coils to find the odor again. I suppose I'll keep an eye open on this to see if the condition worsens.

Thanks for your input here as it was helpful and drop a line if you think of anything else. I appreciate you taking a moment to respond.

Kevin

 

The coils will fail and heat up sometimes. I would pay attention to the way the truck runs. Se if a misfire starts to surface. From the things i have seen on here you got the right guy to give you a hand. good luck and keep the ole truck running strong.

 

Thanks WP - I had a few coils go over the years in other vehicles, so your point is well taken. Unfortunately, predicting the failure as you know is akin to having a crystal ball. No misfiring at the moment and everything appears normal despite the smell. I am heading to the Ford dealership this weekend to get a few parts I've ordered, so I will drive the truck and have them give it a sniff (now that sounds odd). Eitherway, I need to show them the melt through and hopefully get a replacement vacuum line on the house given their tech was the one who put it in harms way. But thanks for the tip and I'll keep an ear/eye open on the misfire potential.

Kevin

 

OK - went to Ford yesterday regarding the vacuum line that melted through and to pick up rear shocks and hardware. A couple of the techs came out to look on what line melted through and spent a minute looking/smelling the coil packs. Their assessment was that it was likely the wires and not the packs themselves at the root of the odor. I will need to do wires and plugs in a few thousand miles, so I will keep my nose to it in the interim and see if the tune up then totally eliminates the smell. In the meantime, I'll keep a watchful eye open for misfiring or other signs of coil failure as noted above.

Thanks for the input gents! Much appreciated!!

 

I'm curious....please be sure to get back if anything happens.

 

TGJ,

I'll do that. I come to the conclusion after reading many threads here that the key to sharing information is with the follow up. I'm hoping that by being as complete as I can, someone will be able to leverage against the information here as I have done from other threads.

I drove the truck to work today and no smell when I got there or when I got home. The only thing I've done was to remove a few of the wires for inspection (the ones that had more browning by the boot) and replacement. Nothing funny that I could tell. I suppose I could do a continuity/resistance check on the wires, but other than the occasional odor, the truck runs normally and returns the same gas mileage (24 mpg around town).

Kevin