Is this a common occurance for a mech to have to take the whole wire harness out to find a broken wire?

Question

diagnosed as p0300 mech says there is intermittant loss of power to #1 coil and he will have to take the whole wire harness out to see if there is a broken wire he charging 82 dollars an hour and says he doesn't know how many hours it will take him to find the wire does this sound like a rip off or what

Answer 1

Depending on what car you have, removing the harness should not be totally out of line. However, that wiring harness has color coded wires and if the mechanic knows which wire it is, then that's what he is looking for. If he doesn't have that information, then you may want to take it to someone who does.
Finding the exact break is tedious, but it is usually at a connection or where a harness feeds through a panel, in this case the firewall. I recently discovered a similar problem came from a GM type of connector which produced the trouble; the connector appeared to be ok, but GM also redesigned the connector because they knew that connections with the earlier design had problems. A good mechanic should know these things, but you have to find out some way. Most of that is by experience.
The codes that machines give out often send people in bad directions. There is no substitute for good old fashioned electrical sense. Three days ago, we had a Caddy which wouldn't stay running. We finally found that the resistor coded key in a Cadillac was not making a connection from the back of the ignition switch; it LOOKED like it was attached but it came off to easily. Re-soldering solved the very unusual problem.
I wish you luck!

Answer 2

No, he won't need to take the harness out; he can check it by using an ohmmeter and wiggling the harness while watching the meter reading.
The coil pack is powered up by one wire, so if the feed power was intermittent, the whole thing would lose power, not one coil. It's much more likely you have a problem with the coil itself, or maybe the module that runs the coil pack. I wouldn't trust your current tech, try for another diagnosis at a different shop. Good luck!

Answer 3

P0300 is a mis-fire code.
The bottom line is do you trust the shop where the car is being repaired? Is it a common occurance, not really but it does happen and usually its by the hour till the problem is solved.I don't know what kind of car it is so i really can't help out on if its a known problem,If you trust the shop let them do the repair but ask the advisor to keep you updated of the cost involved and the progress of the work,if you don't trust them,get the car out of there,...you can e-mail me if ya wish

Answer 4

Not only are you being ripped off, you are being ripped off by a bozo that completely does not know what he is doing and is using you and your car as a training exercise.

I bet the moron never mentioned that you can isolate the offending circuit by looking at the car's electrical circuit diagram. Most likely he is too incompetent to read the diagram or too lazy to research it. Run run run, like the other answerer wrote.

Answer 5

run very fast, he can do a pin check to see if there is a broken wire, it doesnt take removing the whole harness.

Answer 6

That sound like he is taking you to bank and doesn't know what the problem really is. I would take your car to another place and get a second opinion.

Answer 7

Run Run quick don't pay him a dime !!!
He really don't have a clue what's wrong with your car and he's trying to give you a hint. To take it some were else.
It should not take more than one hour to diagnose your car.

Answer 8

No its not common .Ask him if he has heard of a multi meter and a wiring diagram.He is asking you for a blank cheque dont write it .Regards Mick

Answer 9

Find a different mechanic..
Do not have any more work done with this guy...
You are being ripped off by an idiot...