DTC P01300

That's not a valid code. PO130 is an O2 sensor code (related to the heater circuit I believe), and P1300 involves one of the igniter circuits, but I can't remember which one. Are you the dude with the Avalon thats misfiring on #4?

Yes, I'm the dude with Avalon that's misfiring on # 4. P01300 is one of the two codes that were returned from the diagnostic that the Toyota service department conduct on the car. The dealer claims that they need to take the engine apart to figure out what's wrong, but I have the feeling that they're trying to hustle me, especially since being advised, by the fine folks on this forum, about the Leak-Down Test.

So, now I feel that I have enough information to tackle the problem, but I was hoping to get an explanation of DTC P01300 as an added bit of information for resolving this problem.

I gotcha. But, that code you are talking about isn't a code. Too many digits. Can you reconfirm either PO130 or P1300?

Well, that's the code that's on the service receipt, but on the other hand it may not be that important since I think I may have a good bead on how to rectify the problem.

Hey, I have another question for you. If the rings in the cyclinder is sticking, shouldn't there be smoke coming from the exhaust while the car is idling and when I'm driving along. I know that it will smoke in both instances it there's a cracked ring.

cea1

it may not be that important since I think I may have a good bead on how to rectify the problem. >>

I think that if you really do have a ring-related compression issue bad enough to cause a misfire like what you describe then there would be other symptoms like oil consumption and smoke, yes. But, I haven't looked at the car so my opinion in here only goes so far.

Okay, I'm hoping to get an opportunity to do a dry and wet compression check sometime over the next couple of days, I'll hit you back with my findings.

You typed the Code wrong.

P0130 O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)

This code says the O2 Sensor is acting up.

To see a complete list of OBD II Codes, visit

Personally, I think the P0130 Code is a response to the misfire problem. I wouldn't attempt to chase the O2 Sensor issue until the misfire is found and corrected.

A misfiring cylinder will send an unburned fuel load into the exhaust system, and the O2 Sensor can return an out-of-range report that is posted by the Code as an O2 Sensor failure.

I tend to agree with your position here. If there is a ring related issue that is serious enough to cause a misfire, there'd be other issues that would be more alarming -- smoke in the exhaust, oil consumption, that sort of thing. I'm with you though, without having the car in front of me, it is pretty difficult to confirm or deny the dealerships diagnosis. On the surface, I don't agree with them ...

Jeff,

Thanks for your reply! After I'm able to conduct a compression test I'll let you what I came up with!

Again Thanks A Million!

cea1

Hey Jeff Strickland&quo,

I got a chance to do the compression (dry & wet) test on my car today. The cyclinder only produced 10 pounds of pressures during both test. I checked one of the other cyclinders, just for good measure, and found it to have

My next move is have the cyclinder head rebuilt. Should I have both heads reworked or just the one that's bad?

Ray O and qslim, if you're out there, please, weigh-in on this one for me!

cea1

Have them hook up a leakdown checker and confirm it's a valve problem. And if it is, I'd do both sides at once, if for no other reason than the other side can burn a valve or a seat and show up next week. And the head gaskets are a periodic maintenance item. 95 Avalon with a V6, right? How many miles on the engine?

If it's higher mileage (six digits) have them check or do all the stupid stuff while they are in there, like valve stem seals and the other engine external seals, water pump and /or timing belts, freeze plugs, etc. And check the bottom end - pull the pan, and Plastigage the bearings looking for unusual wear.

There's no sense in taking the engine down far enough to do a valve job without at least looking for other potential problems and jumping on the easy ones now. Then you're all set for the next 100,000.

If you start thinking this is getting expensive "Why spend money, I should scrap it!" remember that this car is already paid for - buy a new car, and then you have four or five years of payments to look forward to - a valve job sets you back the equivalent of two or three monthly payments and that's it. And if your car isn't getting rusty, you should be able to top a million miles of good service with reasonable care.

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You can _get by_ with only doing one, but I think you're better off having both heads done because I think you AT LEAST need to look at the other head, and since it has to come off to look at it, you may as well have the valves reseated.

If you need to buy a head, then you need to think about buying two heads or just one.