Please help me! Strange LOUD timing belt noise

[IHMJack]

here is a video

I got a ” P0420 ” OBD check engine light error, the light just popped on when I was driving out of town.

http://www.obd-codes.com/p0420 / http://www.p0420.com/

After about 200 miles later when I got home and parked, sweet smelling smoke was coming out from under the hood (I do not have video for that). The next day when I started the engine I hear very loud strange sound, Im not a mechanic but my best guess is rubber damaging sound, Please help me, and tell me what is going on here and how to fix this problem, leave me comments, thank you for the help!

Topic

[ytram]

I will throw a guess out there.

You did not mention if other work was done, so I am wondering if air condioner pump bearing froze up.

[Daniel]

The sweet smell would most likely be coolant. I’m thinking it’s a bad water pump that is on the verge of completely seizing. That noise is probably a combination of the bearings in the pump and the drive belt for the pump. Grab the pulley for the water pump and see if it moves around at all, check for any leaks around pump and pulley, and please post the year, make, model, and mileage of the vehicle.

[IHMJack]

its a 1996 Geo metro, about 210K miles, how do I check which belt is making that sound? Whats the check engine light about? what the smoking about? thank you for the help

[Daniel]

Either you have a bad catalytic converter or o2 sensor. The smoke is coolant either boiling over because it is not circulating properly or coolant is leaking out of the pump some where and hitting the exhaust.

[Daniel]

For the belt you could try taking the water pump belt off and starting the engine BRIEFLY. I think it is probably the water pump belt making noise so you might as well start with that one cause you’re gonna have to take it off to replace your blown water pump anyway.

[IHMJack]

do you think driving with the check engine light on for 200 miles is what caused the water pump and belt damage? or is it 2 totally different things that is going wrong or is it one thing goes wrong then it caused the chain reaction to damage the belts and pumps? thank you for the help

[Daniel]

I think they are completely unrelated. You should expect parts to start failing with as many miles as that geo has on it. Make sure you keep up with regular maintenance, and make sure you get that water pump fixed, cause until you do you are running a big risk that you could destroy your engine.

[Jeff]

Here’s what I think. Coolant is getting on your belt.

To find out which if its the serpentine belt or the timing belt is pretty easy. Look to see if the outside belt (serpentine belt) is slippery and sticky. If it is, there is the source of your noise.

Now the question is where is the coolant coming from? This is actually pretty easy to find.

Rent a pressure tester: http://www.autozone.com/autozone/accessories/CST-Pressure-Tester-Adapters/_/N-263r?itemIdentifier=84330_0_0_

Here’s a video how to use it: http://www.youtube.com/watch?v=hUzOTnsWImI

most parts stores you can rent for free. You pay for the cost of the tool, use it, and when you are done bring it back and you get a complete refund

Pump it up and see where the coolant is leaking. Once you test it and find the leak take pictures and get back with us for the repair!!

Good Luck!

[Jeff]

As for the code, Check this video out: http://www.youtube.com/watch?v=5icTmYItwiE

I’m from Michigan where we don’t have emissions tests, so I would say worry about that later, get the coolant leak fixed first.

If you do have to pass emissions tests, I would still say fix it after you get your coolant leak fixed first.

[Daniel]

I would definitely NOT follow that video!!! I don’t give a shit what anyone says pouring lacquer thinner in your gas tank is retarded. Lacquer thinner is what they use to strip 100 year old varnish off furniture and it can give you chemical burns.

[dreamer2355]

There are a few easy ways of testing for your P0420.

You can use a pyrometer and check the exhaust temperature before and after the cat. There should be a 100f difference. Also looking at scan tool data on your post cat o2 sensors, the voltage should be around 0.45v. If its fluctuating, then that can be a sign of a failed cat, exhaust leak or a misfire.
Also a 5 gas analyzer will also work.

As for your noise, here is a video that may help –

Keep us posted.

[IHMJack]

thanks to everyone for the advices, when I get sometime I will try to see what the problem is, if the sweet smelling smoke comes out does that for sure there is a leak in the coolant system? if coolant gets on the belts will it make that loud noise? thanks

[Jeff]

Most likely yes, the sweet smell is coolant.

The squeak (loud unpleasant noise) you hear is the belt slipping on your pulley(s) because it is slippery.

The coolant is leaking somewhere by your belt, ie. water pump, reservoir, hose…

If you plan on fixing it yourself find out where the leak is using the pressure tester:

Guaranteed find. use a pressure tester like this one: http://www.autozone.com/autozone/accessories/Tools-Garage-and-Equipment/Pressure-Tester-Adapters/_/N-263r

your local auto parts store will most likely rent it to you. Call them for details.

-Jeff

Good luck my friend!

[EricTheCarGuy]

I’ve written up several responses to the P0420 code. For that reason I’ll ask that you put P0420 into our search function and see the answers on that.

I think the real issue is what’s happening with the belts at this point. It does sound like a belt noise to me. That said I would actually suspect the bearing of the AC tensioner pulley. This bearing often goes bad due to over tightening. It’s easy enough to diagnose. Simply remove the drive belts one at a time and start the engine after you remove each one. If you start the engine and the noise has gone away then you’ve found the effected accessory. If you take off all the belts and still have the noise then perhaps check the timing belt tensioners. Keep us posted on what you find.

[Author]

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