BorderGuy

On a 109 degree day the car began running a little rough and finally going down I-19 at 65mph it stopped running. I restarted it as it was coasting, it ran a couple of seconds and stopped again. Started it one more time while it was coasting, ran a couple seconds at most and stopped again. Of course, this was rush hour and as I'm slowing down I'm able to coast up an exit and before I'm fully on the cross street, I stop the car and call a tow truck, first time in 70 years of car ownership that I need a tow. Nearest garage is a Midas shop and I get there about 5:00pm. They're open until 6 and they can't determine anything at once, but without saying why, they suspect packrats. I get a ride home, 60 miles away and call them the next day. They can't tell me anything because their diagnostician isn't working that day. The following day they call and tell me somewhere between $1200 - $1800. When I ask them why so much, they tell me that they might even have to replace an intake manifold gasket. I'm not confident they know what they're doing and I have the car towed 60 miles to my house. I decide to replace the sparkplug wires and the ignition coils and inspect the wiring feeding the coils for critter damage. I don't replace the sparkplugs because they have only about 3,000 miles on them. I get the car to start, but again it only runs for a few seconds. With my scanner, also confirmed with my neighbor's scanner there is only a P1300 code. What that suggests is the need to replace the ignition igniter - $672 + tax and shipping. I read some of the P1300 threads on this site and I don't get a warm fuzzy about spending $700 for something that may or may not solve the problem. So I buy a used, tested OEM part from eBay for $24, install it and the car starts and runs. I clear the code, start it again, scan it, and no code! The following day I head off to a Dr's appointment get about 6 miles and things don't feel quite right, but it keeps running. Go a total of 14 miles and it stops running. As before, I restart and it runs a couple of seconds and quits. I coast into an AutoZone, they come out with their scanner and the P1300 is back. My first thought is to buy a non OEM ignition igniter from them for $360, but after sleeping on that idea, I'm not so sure that will solve anything. So I decide to have it towed back to my house. The tow truck comes and I am able to start the car, back out of the parking spot and the tow truck driver is able to drive it up onto the flat bed. We get to my house he is able to back it off the tow truck and drive it into my garage.

I did observe at AutoZone when I first coasted in there that the ignition igniter was hot and today after it was parked in the garage the ignition igniter was pretty warm. Don't know if that's got anything to do with the problem.

Unless the underlying problem is as simple as a bad relay, I don't see myself as having the ability to sort this out. Besides a Lexus dealer, are there any recommendations for a competent Lexus technician in the Tucson area?

Any help will be appreciated!

JonGS3

I'm not familiar with that code but hopefully these will help:

FSM troubleshooting section: https://charm.li/Lexus/2002/GS%20300...0Charts/P1300/

And this guy with a 4Runner and the same code traced the issue to his ECU: https://www.toyota-4runner.org/3rd-g...p1300-cel.html

dwoods801

The key is to identify the culprit and don't just start throwing parts at it. You want to start by identifying the actual problem. Determine if its something to do with the fuel system or the ignition system. Once you have identified thqt you can start narrow things down. It sounds like you probably going to need to address some other issues as soon as possible also. But you always want to fix the critical problems before you move onto the things that aren't ideal. You wqnt to get a spark tester from a parts store. It's an inexpensive little device that will attach to a spark plugs and then the spark plugs wire, and then you can have someone start while you watch and if it's got spark, a light will flash. If the light stops flashing, it's an ignition issue and you can start narrow things down from there. If the light continues to flash even while the key is being turned, then it's a fuel issue. You can confirm this with a bottle of starting fluid, just spray some down the intake and see if it will fire up for a few seconds. If thatw the case you probably have a fuel pump issue and you will need diagnose it and go from there. If you find someone who knows older Toyota's and Lexus's, they can do this for you. The problem with some places, like where u took it, they are going to try and make some money on you, never expecting to see you again.

BorderGuy

Thank you for this information.

Now to find someone who can do the 9 step process.

BorderGuy

Dwoods801,
I agree with and appreciate your comments and I plan on getting a sparkplug tester.

I do think sorting this out is beyond my skill set and will continue to look for a very experienced Lexus tech

BorderGuy

Now that it's fixed, let me complete the story. After getting the car towed back home I contacted the Lexus dealer in Tucson along with a couple of shops that specialize in fixing Japanese cars. One of them, Dan's Toy Shop suggested that it was pretty unusual for the ignition igniter to go bad even though the P1300 code indicates that. He thought it more likely a wire issue probably due to pack rats. Hmmm, I'm out in the middle of nowhere and there is no end of critters. I rent a car and take a long planned trip to CA to see a couple of my kids. I come back to find lightening has taken out my well and my wi-fi service. My deductible is $2500 and it's going to cost $400 to tow it up to Tucson and nobody want to give me a not to exceed cost without tearing it apart so I decide to give the wiring going to the coils a good hard look. They don't look good so I replace the connectors attached to the coils a long with the wiring that runs between the valve covers, And, hot damn, I start it up and it idles very smoothly at 650 rpm for 20 minutes with no CEL.