P0171 - Intake Gaset Seal Repair - Tips

[stefan2010_ca]

2005 Toyota Corolla - P0171 Code - very rough idle on start in cold weather.

Intake Gasket seal cost $7 part # 17171–22030
QUoted 2 hours labour or about $275 from dealer to repair.
Followed direction (except draining the coolant) of Toyota Service Bulleting found at http://www.toyotapart.com/M.I.L._ON_...T-EG045-07.pdf

Did repair myself. Took 1 hour. No issues. Cured rough idle in cold weather.

Here are some tips:

1 - STAY ORGANIZED. TAKE YOUR TIME. DO NOT FORCE.
2 - Some clips / hoses are frustrating. Dont force them. Rather pull with a steady, firm pull. If you are forcing you are breaking. Be patient when disconnecting.
3 - Use tape / paper to number each hose and its fitting so when re-connecting you are not confused. I.e. hose 1 goes to fitting 1, 2 to 2 etc.. Will make a lot easier because there are a lot of hoses to dis-connect in order to free the intake manifold.
4 - Use zip lock bags to put the parts in as you dis-assemble so you keep them clean and dont lose them on the ground.
5 - When you get to step 3c,d of the bulletin, have a pen or clean object of similar diamter of water bypass hose you are dis-connecting so you dont lose coolant. Keep hose high when you disconnect till you plug, so gravity does not drain coolant.
6 - If you lose coolant make sure you replace, so engine doesnt over heat.
7 - Careful not to over torque bolts when re-mounting intake gasket.
8 - When you clean the seal of the build up use a clean / fresh rag, careful not to get dirt / biuld up into the manifold gasket. Dont use chemical or water to clean, just use a rag.
9 - STAY ORGANIZED. TAKE YOUR TIME. DO NOT FORCE.
10 - If you feel its not going well, dont be affraid to abort and take it to a shop.

THe repair fixed my problem.

Good luck...

[mikered30]

Nice first post. This will be coming in handy soon with the cold weather approaching as people may get this CEL and want to know how to fix the idle hunting.

[tixxit]

I just mentioned this in another thread, but figured I'd mention it here too. My wife had the same problem and I fixed it similarily to you, but I didn't bother removing the coolant hoses that go to the throttle body. Instead, I simply left them connected, but was a bit more gentle taking the manifold off. The hoses had plenty of give to get the manifold off and replace the gasket.

Also, while your under the hood, you may want to take a look at the MAF sensor. The air temperature sensor (it's a 2-in-1 sensor) on my wife's had a thick layer of grime on it. I sprayed some brake cleaner on it and it went from solid black to amber

[TheUrge]

Thanks for the info - After reading the pdf and your tips, it looks like it shouldn't be too hard of a job if I take my time.

Just waiting on the gasket - should be here Friday.

Thanks!

[matrixjim]

How is the newer gasket diff than original gasket. Is is made of different material? Thicker?

What air temp does the rough idle show up?

[tarbasd]

I just did this job a few days ago. It seemed to have fixed the rough idle, but interestingly it hasn't been really cold here since the job, so I can't say it for sure. A few commnets:

The part number in the original post is wrong: it should be 17171-22060. The OP part number is the number of the old gasket, so you probably can't even buy it. BTW, I paid $11 it.

It's perfectly fine to disconnect the coolant bypass hoses - even if you don't plug them up immediatelly, you will just lose a few drops of coolant. These connections are at a high point in the cooling system, so it's not like the coolant would come gushing out. I plugged the hoses with two bolts. There is definitely no need to replace the coolant - the TSB is crazy, or they want to make more money for the dealers.

There is an apparent design difference between the old and the new gasket. The old gasket has a half oval cross section, and the flat part mated the engine block surface. The new has a full oval cross section and it seems to be completely symmetrical. This made me pause, cause I wasn't sure about the orientation of the new gasket, but then I decided it doesn't matter.

The temperature for the rough idle for my car started at about 40F, and it got worse with lower temps. Never too bad, though, I never had a MIL.

[matrixjim]

ok thanks for info.
Wonder if I should replace the gasket as preventative maintenance or wait for the rough idle issue to surface.
In Calif, the weather normally don't get below 40F, unless your in the mountain area.

[TheUrge]

I replaced my gasket today and overall it was relatively easy.

The only thing that wasn't clear in the TSB illustration is where the VSV was located, and figured out after some additional searching that it is slightly behind and above the air cleaner with one of the hoses that has a green cap on it. Here's a better pic in case anyone's interested:



I did remove the bypass hoses and didn't plug them either...just make sure they don't drop below engine block level and you shouldn't have a problem with any coolant leaking out. Overall it's a fairly simple repair job if you read through the pdf and the tips shared in this thread, and don't rush. It took about an hour from start to finish for me.

Not sure if it has cured my low idle problem, but it should be cold enough tonight to see if it has.

[tarbasd]

After the subfreezing temps here in the last few days, I can now say it for sure that my rough idle problem is fixed.

[Jay-P]

I don't have a rough idle, what i do have is a very high idle on cold, heck even warm temp start ups. More evident on cold start ups though. Could this gasket be my issue?

Again, i have a higher then what i assume would be normal, cold start idle, not rough at all, or hunting.

Thoughts?

[EDIT] Well after doing some searching, which i should have done in the first place... It seems as though my high start up idle is somewhat normal. Still is hard to get used to 2000+rpm cold idle. :o [/EDIT]

[mikered30]

2000 RPM is normal in the cold. The colder it gets the higher it revs, the idea behind it is to warm up fast so emissions are reduced.

[Jay-P]

Originally Posted by mikered30

2000 RPM is normal in the cold. The colder it gets the higher it revs, the idea behind it is to warm up fast so emissions are reduced.

Yup, just seems so hard on the motor, with the oil being so cold and all.

[LynchburgCSI]

PERFECT. Our matrix is throwing a P0171 and we're pretty sure this is the problem.

[relee]

According to the service bulletin you need a TIS techstream software version is this required to fix this problem or can I go ahead and replace the intake gasket and not worry about it Thanks

[mikered30]

If you are sure it is the gasket, you do not need he TIS software. You can diagnose it with some carb cleaner.