I remember one period back in the mid-1990s when was seeing a lot of fuel pump failures. The vehicles would come in on the hook with no fuel pressure, and I’d check to see if the inertia switch was tripped. Then I’d toss a fuel pump in there, fire it up and test drive it, and all would be well. I was fully aware of the possible wiring concerns and whatnot, but I had seen so many fuel pump failures that I didn’t see the need to spend a lot of time data mining.
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ENTER CODE : ART30 AT CHECKOUT
I got a little too comfy with that pattern, and there came the day I drew a work order on a Taurus that my neat little routine didn’t fix. I got that hook rider in my service bay, didn’t hear the pump, checked the inertia switch and replaced the pump, all to no avail. The new pump didn’t run either, and I felt like a dummy when I discovered a chalked up ground wire at the battery terminal. I’m an honest guy, and as I perused the notion of removing the new pump from the tank and reinstalling the old one, I was hit with the realization that if I did that, the old pump could (and probably would) fail within our service warranty window and then I’d be stuck with having to do the next repair for free. The ground chalk was erased and the new pump remained in the tank. I could have saved a life, who knows?
This Lincoln’s driver had driven it bucking and jerking with the Check Engine light on for about three months until her father drove the vehicle one day, felt the problem and told her something needed to be done about it, and so it wound up at my shop. We drove it, felt the jump, snagged some cam sensor codes and scope patterns (verifying cam misalignment issues) and postulated there might be a phaser problem.
The PICO scope pattern we got from the two cam sensors and the crank sensor pointed to a concern on the No. 1 bank’s camshaft. Was it a phaser or not? We removed the sensor, bumped the engine over until the three-prong side of the No. 1 banks’ phaser’s trigger wheel was lined up with the hole and looked to see if the arrowed “L” symbol on that gear was out of line with the center prong. If the phaser was out of phase, the arrowed L and the prong won’t eclipse.
This one seemed to be a shade off, but not enough to account for the pattern we got, so it was time for exploratory surgery. With the valve covers and the timing cover off (no small feat), we discovered the real problem, which, it turns out, is more common than phasers. The straight fixed slide on the upper stretch of the No. 1 bank chain had disintegrated and that chain had been whipping around in there to make some pretty serious marks on the inside of the cover. This one would get a couple of phasers after all, along with new timing chains and all the stuff that goes with it. The guy I had doing the job was (and is) one of the most conscientious and careful second semester students I’ve ever seen, and I kept everybody out of his way while he plowed into that Navigator with one of the computers rolled over to where he was working. This B level job would have been a 14-hour flag for a line guy.
Those Crazy Others
Four more vehicles rolled in while the Navigator was under repair, a 1999 Town Car with a stubbornly steady number four misfire, a 2002 Taurus the owner said had an under-load bite at 45 mph (all too familiar), a 2004 Tahoe with an intermittent no-start problem and a 2001 F150 with electrical gremlins – the instrument cluster was remaining illuminated with the key off, complete with fluttering odometer segments and a dead battery after sitting overnight.
The Town Car’s No. 4 plug well was loaded with coolant, which led us to examine the heater hose fitting right above it. Sure enough that pressed-in hose pipe was leaking coolant into the spark plug cavity. That one got an intake manifold.