Ford is having some major spark plug problems. The 5.4 before 2004 is the worst but there are several other engines having the same problem. When the heads were machined the spark plug threads were not cut to the bottom of the hole and this causes a plug to blow out. Usually a tap or in worse cases a heli coil will fix the problem. 99% of the time cranking the engine over will blow out the majority of the material left in the cylinder. Be careful the crud comes out with a lot of force. When Ford corrected the problem they used a plug with 2 pieces and a little too long causing carbon to build up on the end and making the plug almost impossible to remove if left in for the 100K recommended replacement. To remove a stuck plug warm up the engine so the head just feels barely warm to the touch. Spray a penetrating oil, I use sea Foam deep creep do not use WD40, to fill the hole and back out the plug a 1/8 of a turn then let it sit for an hour or so. When removing the plug you may have to turn in and out while applying more chemical. If you do break it off there are several tools available to assist in removal. Be sure you use the newest Ford part as a replacement they are of 3 piece construction. Using anti seize is personal preference but be sure to torque them.
One of the hardest problems to diagnose is the traveling miss. It’s when a cylinder misfires and seems to move from one cylinder to another almost at will with no obvious reason. The primary and secondary ignition all check OK and the fuel delivery system shows no problems. You may think a vacuum leak is the problem and this is a possibility but rarely is it the problem.2 things can cause a traveling miss and the first is a defective ignition module which is easy to diagnose. Hook a lab scope to the power wire for the module and it should show the same number of spikes as the number of cylinders. If one is missing replace the module after checking the ground. The second is rare but we seem to be seeing it on a regular basis lately and that is AC voltage from the alternator. Here again it is easy to check and you don’t need a lab scope which is becoming rare when diagnosing problems lately. With a voltmeter hooked to the battery and set to the AC range of millivolts you should see no more than 0.4 or 400 millivolts. To further check and a easy quick check is to unplug the alternator and if the problem goes away then check for AC voltage at the battery to confirm your diagnosis.
Burn time seems to be a term that many do not understand. I used it in my Vacuum gauge topic and it has brought up a lot of discussion. It is simply the length of time that the fuel in the cylinder burns as measured by a scope or engine analyzer. The longer the burn the less efficient the cylinder is performing, usually caused by low compression. With today’s cramped engine compartments it helps to narrow down a problem cylinder rather than do a compression test on all cylinders. I think more techs are using a leak down test on problem cylinders as this provides more information than a compression test. If I had my vehicle in a shop and they wanted to do an outdated wet and dry compression test I would consider going elsewhere, sure it works but there are tests that will provide more accurate info. Many shops are at $100 an hour so any time saving tool they use is saving money. I do think that many of these new tools and test equipment that are necessary to work on the modern vehicle is slowly moving the DIY out and forcing them to go to a shop. More on this later.
I took some heat for my topic on the Gates belt inspection tool. One of the reasons I do this is to stir the pot and bring forth controversy. As I have said before Techs have a hard time agreeing on anything that has more than one option. One item of discussion that I agree with is that the vacuum gauge is also a tool that is not high tech but is a very useful diagnostic tool. Yes, there is a vacuum transducer that connects to a lab scope to help in locating a miss but to quickly determine engine condition or help diagnosis a no start you can’t beat the ease of use of a vacuum gauge. I also agree that we use a lot of flashy tools that could be performed by a simpler one. One case in mind is the non-contact stat many times we could use a regular stat but we grab the non-contact, because of ease of use and why have it if you are not going to use it. A recent tools magazine showed a techs new tool box and it was over 6 feet high, how do they access those top drawers without a stool, it was at least 15 feet plus long. I would guess he had more invested then my first house cost. But then our tools were worth about the price of a car so with that in mind they are about equal. I do wish I still had a shop so I could justify buying some of the cool new tools. Labor rates exceeding $100 an hour in many places, with the cramped engine compartments and complicated systems in today’s vehicles today’s techs need every tool they can put their hands on to make their job easier.
Gates came out with a gauge to use in inspecting there new belts, they have a square groove, and can wear without the tell tale signs of a regular belt. I have waited for this tool for some time, I know I need to get a life; it is a little plastic rod with a thumb hole on the end. I was totally disappointed in today’s shops there is a ton of sophisticated very expensive equipment and this is what I am expected to use to check one of the major parts on a vehicle. Next to brakes and steering I feel the belt is an important part of the vehicle. This does not even look like it would be a decent selling tool as I think to buy something customers like to touch or at least see what they are buying. IE Transmission fluid looks dirty, fuel filters are rusty but this little plastic thingy looks like it belongs in the drawer with the obsolete tools that you just can’t bring yourself to throw away. It is designed to be a selling tool but I still think the old visual inspection is still the best way to. I can see it being used if you have a noisy belt and cannot locate a cause and want to eliminate the belt as it will take some time for us to learn the traits of this new belt.Look on the bright side I got something free from gates and it brightened my day.
From a latest post it seems some DIY are having problems checking for a bad injector. It is really not that difficult. One tech recommended warming up the engine and removing fuses and draining the pressure from the fuel system. None of this is necessary to check the injectors, if they are accessible it doesn’t hurt to warm up the engine for a few minutes but in most cases by the time you gain access the engine has cooled off. It is necessary to remove the fuel pump fuse and drain the pressure if you are going to replace the injectors or remove the fuel rail.The simplest method is to listen to the injectors with a stethoscope if there is a bad one it usually will have a different sound you can also use a long extension or screwdriver as a stethoscope but this will not work as well and a stethoscope is cheap. This method will find a bad injector but will not rule out the possibility of a defective one as they do not always have a strange sound. You can also ohm the injectors at the connector that feeds all the injectors easy to get to and you can usually determine which bank the bad injector is on thereby possibly eliminating some unnecessary parts removel.Here again will usually locate a defective one but will not eliminate the possibility . The only positive method is to gain access to the injectors and check them individually I won’t go into the readings here as they vary by manufacture but usually the defective one will be way off from the rest. Be careful I have seen many with several defective injectors. If you have access to a lab scope this is an excellent method also cool to watch the injectors fire. A scope with a burn time option can also find a defective one . I know injectors are expensive but think about replacing them all as with plug wires sure as the sun will rise in the AM another will go bad soon after your repair is finished. There are several aftermarket suppliers and remans are an excellent replacement choice.
We have had some terrible weather lately it either snows or is -20 or worse, highest snowfall for any month in Dec. I think a word of praise to the automotive techs and mechanics is in order. There is a difference between a technician and a mechanic or wrench. I don’t know how the techs of today keep up with the technology; today’s cars have more lines of computer code that the first manned satellite. Many of them have a PCM, ABS and body module and some have HVAC and security, among others. I have been retired for 4 years now but I still get involved in problem cars at several shops around town so I do keep my fingers in but I can see a time when I will no longer be able to do this. You have be involved on a daily basis or it is impossible to keep up. Today’s techs have to have computer knowledge and a thorough understanding of troubleshooting electrical systems. They also have to have training in AC, Power Steering, transmissions, brakes, security and sound systems. As all of these are computer controlled on many vehicles. Most techs will focus on 1 or 2 systems, but what do the smaller shops do. With ground controlled, low voltage and now hybrid. They deserve a pat on the back for the job they do. Add to this a minimum of 10,000 to 15,000 dollars in tools or in many cases more. They are severely under paid for what they do. I know several that have degrees and can make more repairing cars than they could be working in their field but I still think the majority are under paid and underappreciated. A wrench is the back breaking work R&R transmissions, engines repairing leaks or the lesser skilled repairs. They are definitely underappreciated, more so during the cold weather we have had. As far as pay goes it is all over the scale. This is where I started but then there was no such thing as a tech. I remember when the Dodge Charger came out with a lean burn controlled carb and ignition system, About 35 years ago, I was a service Manager in a Dodge dealership and one mechanic threw up his hands and quit saying there was no way he was going to work on it. What would he say today, I know several times I have opened a hood and wanted to say the same thing on some of the newer vehicles.I was lucky to have been involved with computers both in the home and auto version since the beginning and I feel this has helped a lot in my understanding and repairing problems over the years.A big pat on the back to all the techs and wrenches out there and thank you and keep up the good work.