On a slightly different note, I used to hang out when I was off work at Sambos drinking coffee back in the late ‘70s with some of the locals in Port Arthur, Texas, and when I overheard one of the patrons asking a young waitress about her car, she told them she had a ’63 Buick Special but that the “motor had burned up” and she couldn’t drive it. I chimed in to ask if she had run it out of coolant or oil, and she told me it had caught fire under the hood while she was driving and had been sitting in her parents’ driveway for months.

She went on to say that they had given her a coil, a distributor cap and some wires for her birthday, but nobody they knew wanted to attempt the fix and they couldn’t afford to hire a shop to do it. I asked if I could take a look, and she agreed, so I dropped by her parents’ house and opened the hood on that little V6 to find that the engine fire had been wall to wall – the wire harness was little more than a bunch of bare wires, and the ignition components were, as expected, nothing but crust and ash. I wondered if I had bitten off more than I could chew; I couldn’t even tell where the fire had started or why, but I dove in headfirst. 

Retrieving some rolls of wire I carried in my truck toolbox, I carefully unplugged the mostly melted wire harness from its various connection points and using cheap butt connectors and electrical tape (I wasn’t going to spend the time it’d take to solder and heat shrink everything), I rebuilt that underhood harness one wire at a time on the tailgate of my pickup, then plugged it all back in and installed her new distributor cap, wires and coil. I hooked up my jumper cables, we spun it over, and it fired right up and ran like a champ. The whole job only took a couple of hours, so I charged her $25, and she paid me with multiple rolls of coins from her tip money.

The Commander

A friend of mine brought his son’s 2006 Jeep Commander, 4.7L V8 with a 5-45RFE transmission and 187,854 miles on the odometer, telling me he believed water was making its way into the #8 cylinder, because the vehicle had overheated a few times and now it was misfiring on that one. We found his misfire on the cylinder he indicated, but a quick look at all the plugs didn’t show any evidence of coolant ingestion at all, only a sooty plug on the dead hole. So, my man Charles tossed a set of plugs in there, and in the process of our testing we discovered the compression was low on that cylinder. Further, Charles said that with it idling he was hearing something under the valve cover he didn’t like, and to get the valve cover off, he had to recover the refrigerant.

When we did the refrigerant I.D. with the Peter Coll Neutronics tester (a shop should always do that!), we got a big fat red FAIL light – 5 percent hydrocarbons in there, possibly from some fly-by-night canned stuff. We had to use our dedicated tank and machine to suck that garbage juice out. When Charles got the valve cover off (no fun), he found the rearmost roller rocker out of place and lying fallow on the head. How did this happen? Somebody else might know, but I don’t. We removed and collapsed the lifter so we could get the rocker back in without too much trouble, and that took care of the engine skip, but we weren’t finished – not by a long shot. More about that one in a minute.

The Buick

One of our staff drives a 2007 Buick Lucerne that was purchased from the local GM dealer as a very clean used vehicle, and it’s outfitted with that tried-and-true 3.8L V6 GM used for so many years. It had been sporting an MIL light for awhile along with a P0420 code, but the director in charge of our vehicles said the catalyst had already been replaced with an aftermarket unit before the car was purchased and he wasn’t concerned about that. What did turn out to be a concern after a few thousand miles was that the Buick died and came in on the hook with no fuel pressure.

It was interesting that about this same time, the 2001 Tacoma driven by the director died from a lack of fuel pressure as well. We ordered a Delphi fuel pump from the local parts supplier for the Buick and initially ordered a fuel pump for the Tacoma, but after we got the Toyota pump out, we found somebody had already replaced it (just the pump, not the whole thing) and did a crappy job on the in-tank wiring patch, so we got rid of the butt connectors, fixed the wiring the right way and sent the pump we had ordered back to the parts store to get the Tacoma done.

One of my people rolled into the trunk on that Buick with an air ratchet and a fan blowing the fumes away and replaced the pump module with a new Delphi unit, but then about six weeks later, the pump died again, and this time, since we were between terms and I was off work, the Buick wound up at the GM dealer where it had originally been purchased – and the director called my cell phone to say that the dealer said the pump was bad.  I called and explained to them that the pump was a Delphi pump, but they said since they didn’t sell that one to us, they’d need us to get a replacement pump from the parts store – which I did, and they installed that one – it was back on the road.

Well, the odd thing that happened next was that when the car was started after a hot soak it’d immediately die and would need to be re-started, and we found the second new fuel pump failing to hold rail pressure after the vehicle was shut down. A third replacement Delphi pump held rail pressure at shutdown, but sometimes the car would still pull that odd start-and-die stunt. This was getting interesting. Further, there were a couple of times when the car would either lose power or just quit while driving and fail to re-start, but we could never duplicate this. We DID, however, get it to start, die, and then spin about 10 seconds before starting, and we got it to repeat this somewhat regularly, if not every time. And while it had nothing to do with this start-die problem, we obtained a Walker bolt-on replacement cat to get rid of that annoying P0420 once and for all. And it did.

For the other issue, I broke out the Waekon Industries Flight Recorder® (WAE-45364), which is kind of pricey, but records ignition, fuel injector pulse, battery power, and one Auxiliary data plot of your choosing in an internal buffer when you tap the record button, and the graphs can be retrieved on your PC with the dedicated software.
 

We had successfully fixed a Chrysler Crossfire that had stumped the Chrysler dealer using this same tool (see “Methods, mysteries and frustration,” May 2013), so we used the tool on the Buick and found that, when the concern was duplicated with the auxiliary measuring power to the injectors, there was indeed power to the injectors. However, the spark and pulse weren’t consistent during the extended spin. After replacing the crank and cam sensors to no avail, we replaced the underhood fuse box because it has a gaggle of those integrated relays that can’t be replaced — one of them being the run/crank relay; if that relay doesn’t deliver power (or not enough power) to the PCM, we reasoned that it might cause this concern. It was a Hail Mary pass, but at the time of this writing, about six weeks has gone by with no further complaints.

The 2007 Silverado and the Fusion lug

This truck came in for a routine service and an oil leak, and when we applied the dye and the black light, we found the oil oozing out around the oil filler cap – which was peculiar, but not unheard of, particularly on these GM V8 truck engines that have the PCV system integrated into the driver side valve cover. The students who did the service also reported moisture in the crankcase, another indication of the PCV issue. We replaced the valve cover and those concerns evaporated.

On a side note, we found a Camry leaking oil from around the oil filler cap too, but it turned out that one just needed an oil filler cap.

We were doing a routine tire rotation on a 2012 Fusion when one of my people came to report that one of the lug nuts was spinning round and round on the left rear and they couldn’t get the tire off. That one was because of a nut that was initially cross-threaded and impact-forced right at its tip. This wasn’t the first one of these I had seen – we had an Altima with the same issue awhile back, and it was a bear. The folks who use an impact wrench with no torque stick tend to think that too tight is better than just right, and after a little of that, the threads begin to gall and sometimes the nut just won’t move. If the splines on the stud are sufficiently strong, the stud will break off. If not, they spin in the hub, like this one did, which becomes something of a problem.

I’ve seen this more than once — this lug nut was crossed up by somebody on the starting threads and then they tried to force it with an impact wrench, which effectively welded the lug nut to the stud. In other cases, the impact wrench distorts and galls the threads all the way down due to overtorqueing.

I used a two-pound hammer to drive an old MAC prybar in between the wheel and the hub with enough force so that we were able to foul the head of the lug stud and get the nut off, and then we replaced the stud and the nut. At my shop I teach them to spin the lugs on there with the impact on its lowest setting and then follow up with a torque wrench. Then I place the students in shops where all that careful torqueing (and even the practice of wearing safety glasses) goes out the window and they wonder why I even taught them that to begin with. Oh, well.

Back to the Commander – and a Dodge

In search of the overheating problem, we noticed that there were coolant stains on the exhaust back below the heater core area and we initially thought there might have been a heater core issue, but then, there was no coolant in the passenger side floor. Was this one of those with a secondary drain for a leaking heater core? No, there was a hose issue of some sort going on back there, and initially we found that one of the clamps was loose and dangling, but that wasn’t our leak either. What we found was that somebody had replaced an original heater hose tee with a plastic one that looks like it came from a hardware store – it was a size too small, not made for coolant heat, and was cracked to boot, and the clamps had egg-shaped the plastic. It’s a wonder it was holding coolant as well as it was.

We replaced the tee, pressure tested the system, liked the results, and then drained the radiator, which didn’t have much coolant in it. On this one, because the thermostat is in the bottom radiator hose, you drain almost nothing out of the engine block unless you yank the ¼ inch pipe plug out of the side of the block to let it gurgle out of there – we did that. Afterward, I wanted a full load of 50/50 in there, and I poured it in through the upper radiator hose with a funnel to fully purge the engine block water jacket of air before we did anything else. Remember, the thermostat is in the lower hose. Toyotas, old VW Rabbits, and some other platforms are built this way. Incidentally, Ford’s 2.8L V6 was configured this way as far back as the ‘70s (think Mustang II).

Okay, so we fired up the Jeep and let it run for a while – there was a Check Engine light, and among some other codes, we got one for a cooling fan issue, and this had been an overheater – so we went back at it.

This is one of those Jeep vehicles that has a belt-driven fan AND an electric fan, and we noticed that somebody had pocketknife-shaved the cooling fan wires in spots, probably trying to see if there was power to the fan. We checked the fan electrically with a test light wired in series but found no open segments. Pulling both fan relays, we found no power at their common terminals, and that’s when we noticed that blown 50-amp fuse that probably happened when somebody was fiddling around with the fan wiring. With the fuse replaced and a smooth re-test, the fan came online and everything was dandy.

Speaking of Chrysler V8 overheating problems and customer bought parts, we had a 2006 Charger that came to us with a new radiator in the back seat that the owner had purchased online, along with specific instructions that we were to replace the radiator first – in true form, they had a friend of a friend do the troubleshooting and he told them that was what they needed. We followed those instructions (replaced the radiator) but we also did a pressure test, which revealed the actual problem — it had a leaking water pump, so we did that too. But once again, we weren’t done yet. In sewing that job up, we noticed the fan (a dual unit) wouldn’t run, and our test light test of the driver side fan motor revealed an open motor. With a new dual fan, a new water pump, and a new radiator, that ‘06 Charger was cool to go.