You were on the right track with the MAF. Was the new MAF a toyota MAF or an autozone MAF? Does this happen when cold? Did you check for vac leaks? There is a new TSB: 04507 for your code with the following symptons:

TSB04507 is for replacement of the intake manifold gasket that causes rev hunting, which sounds like your problem.

Following a cold soak in subfreezing ambient temperatures, some 2003 - 2008 model year Corolla and Matrix vehicles equipped with a 1ZZ-FE engine may exhibit a M.I.L. "ON" with one or more of the following Diagnostic Trouble Codes (DTCs) as the result of a vacuum leak at the intake manifold.

^ P0171 - System Too Lean (Bank 1)

^ P0300 - Random Multiple Cylinder Misfire Detected

^ P030 # - Cylinder (1-4) Misfire Detected

^ P0133 - Oxygen Sensor Slow Response (Bank 1 Sensor 1) Please use the following procedure to repair the vehicle.

You are out of warranty, so you pay cost (parts + labor + diagonstics=$$). New part number for the gasket is 17171-22060, costs $6 from the dealer and you might be able to repair it yourself to save some money. If I am wrong you are only out $6 and 2 hrs of your time.

If you can return the new MAF I would and clean in put in the old one if you still have it.

 

i had that code a while back, i just sprayed the MAF sensor with some MAF cleaner, the light never came back on again.

but in your situation, i would check the the main oxygen sensor (the one on your exhaust manifold, not the one after your cat)

 

The MAF sensor that I bought was from autozone, and I can't take it back. I can exchange it since it comes with a lifetime warranty.

I have noticed lately that the rpms are a little strange.

I am very much a diy mechanic, and think that would make sense about the intake manifold gasket.

Does anyone have a diagram or instructions or even pictures to show where it is and how i go about replacing it.

When I say DIY mechanic, I mean only the easy stuff.

Thanks for your assistance.

 

I have the same problem . My cars idle is a little low and I can feel a slight vibration in the engine bay. I even had the CEL diagnoced and it is the same code. I cleaned the MAF with little or no progress. Today I tried spraying the intake with intake cleaner but it doesn't seem to change the revs but, then the cars revs are only a little low and I can't notice the difference. I was wondering if you got a fix on this.

 

I have looked some more information and found out that it possibly has something to do with the intake manifold gasket.

The "rev hunting" is caused by a air leak.

According to several sources, the intake manifold gasket is known to go bad in 03-08 corollas and matrix.

I have ordered one. It doesn't seem to difficult to put the gasket on.

Yesterday, I checked the pcv valve and all the hoses. no leaks.

I'll keep you posted.

I should get the gasket tomorrow.

 

Cool Brandon let me know what happens. If it fixes your problem I guess I will have to do the same thing. How much did the gasket cost you?

 

$6

 

Well, I replaced the gasket and the car got a little better. The gasket actually cost me $8.96 but was very easy to put on. There are actually two different part numbers for this car depending on where your car was made my cars part number for the intake manifold gasket is 17171-0D020.

 

When you say a little better, did it fix the problem?

 

My problem was very minor. My idle was a little lower than it should have been and I had the check engine light on. I have driven 600 miles since I did the work and no check engine light but the idle is not always correct. The idle could be better.

 

Great News!!!


The gasket fixed the problem. The car runs like a dream now.

All together it probably took 30 mins max to take off the gasket and install the new one.

Thanks Mike!!!

By the way, the felpro gasket cost me 22.00, but I'm in sc.

The car does not rev high anymore. I was already getting 37+ mpg, city, can't wait to see what I'm getting now.

Thanks for all your help!!!!

If anything changes I will post it back here.

 

Nice, so you did not have to drain the coolant?

 

You know, I didn't have to drain the coolant.

However, the heat does not seem to be working the best on the car. I'm thinking that there may be some air in the system.

Does anyone know where the bleeder valve is to remove the air from the engine?

Thanks

 

Hi Brandon I'm glad your problem is solved. Why do you say felpro gasket I thought you were going with the Toyota gasket? My idle is still a little on the ruff side. My car used to idle at 900 rpm when in gear. I am now gettin approximately 850-870. I just hope the light doesn't come on again. How is your idle?

 

My corolla is a 5 speed, but it idles around 700 rpms.

When I used to start the car up it would idle at 2,000 or more rpms and stay there for a while.

Now I start it up, and the car goes to about 1600 rpms then backs down. it doesn't stick at higher rpms.

I used a felpro gasket simply because the closest toyota dealer is over a hr away.

 

My car is an automatic so I need a higher idle. 7oo would be two low for my car. I still feel the engine because my idle is low. My check engine light is still out but I have a feeling it is going to come back on. Did you return your MAF or did you keep it in the car? I think I may need the MAF to deal with my problem. Our cars are also different because I have the drive by wire throttle and you have the cable. Besides the idle problem my car is running excellent.

 

I kept the maf sensor in the car.

What about your Idle Air Control?

That was going to my next bet if the gasket didn't solve the problem. I could hear the iac ticking.

 

Funny you should mention the Iac because under further observation the 2005 does not have one. I have the Haynes manual and they talk about the IAT which is the Intake air temperature sensor which controls the fuel flow and timing and it is part of the MAF. In the 2005 the TPS which is what basically controls the throttle is not a single unit, it is part of my electronic thottle. I'm thinking it is my MAF. I guess I'll be buying that next.

 

I hope that fixes your problem.

Please post back if it does.

 

Well, the check engine light came back on.

After about 150 miles. I have no idea what it could be now.

The car still revs high when you start it. I know that it should to a certain extent, but it shouldn't stay at 1800 rpms for more than a minute.

Somebody, please shed some light on this for me.

I'm about at my wits end with this problem.

 

Wow Brandon that sucks. If I were you I would get the codes read again. Maybe it's another problem. My car idles at approximately 1900 rpms when I first start it in the morning but, that only last for appox 10 seconds. I am still having my problem with the car idling lower than it should but still no check engine light and it has been 1000 miles. How is your car running besides the light.

 

Well, I have a friend who works at a local toyota dealer and I went to the dealer Saturday.

They hooked my car up to the computer and diagnosed it for me.

It is my mass air flow sensor and my catalytic converter.

I had purchased my sensor from auto zone for 86.00. DON'T EVER BUY A SENSOR LIKE THAT FROM AUTO ZONE!!! The technician from toyota explained to me why. He also told me that since the system was not operating properly, the cat had to work much harder, causing it to go bad.
The tech also said that code is extremely common in 03-07 corollas. I hate to take my car to a mechanic, but I was extremely pleased with the techs expertise.

I do have good news to bare though. My car has 60k miles on it. Emissions have a 80k warranty. So, they'll replace my cat for free!! That's great too, because it would have cost 1,200 just for the cat, not including labor.

I'll still be out for the toyota sensor. $113.00.

They have to order the parts, and are expected to be here around Tuesday or Wednesday of this week.

I'll keep you informed.

 

I tend to try to stay away from non-OE parts as well. There's a reason the AutoZone part is only $86. Who knows who makes it, where it's made, how many vehicles it's "supposed" to fit, etc. I wouldn't replace the catalytic converter yet, if I had to pay for it. Your car's code indicated that you had a lean mixture. Rich mixtures burn up cats, not lean ones. Unless there was a specific code that indicates catalytic converter non-performance, I'd have waited on that until the MAF sensor was replaced and you've driven a few hundred miles to let everything settle out. But since they're going to replace it under warranty, that sounds great.

 

That's something else as well.

According to the obdII reader from auto zone, the only code it pulled was the system too lean code. But, on the toyota computer, it came up with system too lean code and cat coverter. Just goes to show you, that i probably could have saved more money if I had gone to the dealer in the first place.

You live, you learn.

 

Brandon remember the second code may not have existed when the autozone did the check. Anything can happen from one day to the next.

 

If the AutoZone scanner didn't read the code, the code wasn't there. I would ask the Toyota dealer what code the catalytic converter was. There are a number of OBD-II codes that could indicate a malfunctioning converter. I'd put them on the spot (it IS your car!) and ask them for the code, and see what they say.

 

The codes that the dealer pulled were p0171 and p0420.

p0171:system too lean

p0420: Catalytic Converter below Threshold

I feel really confident that this should work.

 

I hope it does but, I still think the code came on afterwards and it wasn't there before. I have a question. Did your idle go back down or was it normal? I am curious because if your idle went back down and the new MAF fixes the problem then that is probably my problem. Please let me know.