Newbie with Aveo in need of timing belt/head help

Hey all,

New here but been lurking for a few weeks. I guess I'll start by explaining how I came across my 05 Chevy Aveo. My friend decided to drive cross country from MA to AZ. I warned her to make sure everything was up to speed on her car maintenance before she left. I specifically mentioned the timing belt after looking up the interval it should be changed and reading the horror stories. She decided to chance it and broke down in WV. The shop there quoted her $2000 for repairs so she was going to just leave it and let them have it. (!) When I started saying how crazy that was, she said if I got it here I could have it. So... $725 later it arrived in VT.

Once I dove into it found that the timing belt didn't actually break... the plastic idler pulley shattered and chunks melted/wedged themselves at the bottom against the crankshaft pulley. Even though I knew it was an interference engine and had most likely jumped time I decided to chance it and just install a full timing belt kit and see if it cranked. Did that last night and nothing.

So looks like my next step is to pull the head and check for valve/piston damage. Going to work on it this week a little at a time after work and into the weekend. Any tips for pulling the head? Can I easily tell if the head needs to be machined or just the valves replaced? And if just replacing valves is this hard to do myself?

Thanks for bearing with me on the long post. I'm used to working on VWs so this car seems nice and simple compared.

-Dan

You said you tried to crank and got nothing - I'm assuming it did crank (turned over), but didn't fire and start up. Is that correct? If so, did you at least do a compression test, if only to get a baseline of where the engine is currently at?
I (fortunately) haven't needed to do head/valve work on mine, but from what I've read it doesn't sound like anything out of the ordinary for that type of job.
Now here's one other thing to consider. When these interference engines go bang and bend valves, that means those valves have made some major contact with the pistons. So my question on this has always been, what does that contact do to the bottom half of the engine? I'm thinking about not just the obvious damage to the top of the pistons that can be seen. but also everything else, right down to the crank. We get people posting about replacing valves or installing a new head, but generally that's the last time they post. I don't have any real warm feeling that fixing the head issues will result in an engine that will give many more trouble-free miles. Do most of these head/valve repair jobs go South a couple thousand miles down the road due to bad bearings? IDK - I'm obviously not a pro who does lots of these jobs, so it's all speculation on my part. It would be great to have a mechanic post that they have done many of these jobs resulting from interference valve bends, and none came back later with lower engine problems. Until that happens, JMHO but I would skip the head repair and drop in a new engine instead.

I agree with Avguy. I got mine like you got yours, except the previous owner tried to start doing the work himself, then he gave up. A salvage yard engine can be only slightly more expensive, and its pretty easy to drop in. With any luck you'll find one with less miles than the original engine.

Id use this as a swap prodject. Since the engine is gone do the cobalt ss swap find out what you need and sell what you dont. This idea is based on if you have a current runnig car to drive while its under the knife.

Wait hold up if your used to working on vw then you should be the first to swap a vr6 into an aveo
.................It would be epicAttachment 6342

Haven't done a compression test... I figured at this point that I would be ripping it out for one reason or another. Don't have very many salvage yards around here so finding a used motor might be tricky. They're all around $1000 on eBay. After doing the whole timing belt kit and it not working (which I knew in the back of my mind anyways) I needed a few days away from it. Might finish pulling the head tonight. The car is in great condition overall but there are some bolts (mainly exhaust manifold) that are quite rusted on and holding me up. Will update once it's pulled.

Got the head pulled! All 8 exhaust valves are bent with a little bit of the head dinged up around where they seat. Is this a big deal? Wondering if I should play it safe and send it out to be checked out/valves replaced or attempt to do it myself. Intake valves looked ok but didn't make a point yet of rotating them out to see if they're damaged. Pistons look ok too... just a slight grazing where the valves made contact. My mechanic said they should be fine as long as I make sure there aren't any burs that could cause hot spots.

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All said, that actually doesn't look too terribly bad. If you've done valve work before, you should be alright, if not, having a shop recondition a head all around for you should be fairly cheap considering what you paid for the car, especially.

Alright finally an update! Money has been tight lately so been ordering stuff when I can. Got all the exhaust valves out today with this sweet spring compressor I got from Amazon.com

Attachment 6433

Here they are next to a new one:

Attachment 6434

Upon getting them out I found I have some broken valve guides too. Like an idiot I didn't order them yet hoping the old ones would be ok. Getting those ordered today since no one around here stocks them. So much for getting the car back together this weekend. Any tips for getting the old ones out/pressing the new ones in?

Well after 9 1/2 hours this past Sunday, she's all back together and runs great! Smooth quiet idle and drives nice. Couldn't find where one wire connector goes (pic at bottom) but in the meantime it doesn't seem to be affecting much.

After new valve guides, valve seals, and of course valves putting the valve keepers back in. I was surprised these went back in a lot easier than they came out.

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Head back on and new timing belt kit installed:


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All together! (Except for the air box... screws were all rusted in so we had to cut them out... back in now)

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The one mystery wire that I can't find a place for. If I remember right it's on the same section of harness that goes to the alternator. Not very long and I can't find anywhere it could reach to. It's pretty clean so I'm sure it was plugged in before. Anyone have any ideas or pics? Driving me nuts.

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Originally Posted by DRG2003

The one mystery wire that I can't find a place for. If I remember right it's on the same section of harness that goes to the alternator. Not very long and I can't find anywhere it could reach to. It's pretty clean so I'm sure it was plugged in before. Anyone have any ideas or pics? Driving me nuts.

http://www.aveoforum.com/forum/attac...421_172920-jpg

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My guess is: Power Steering Pressure switch. idle should come up a bit when you steer while not moving

+1 on the VR6 swap :)

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Originally Posted by JusteR

My guess is: Power Steering Pressure switch. idle should come up a bit when you steer while not moving

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RPMs very slightly drop when turning the wheel when idling. Does that confirm that's what this plug goes to? Any easy way of explaining where it connects? I'll poke around next time I get under the car and see if I can get this last thing done. Thanks!

Isn't there a two wire (coolant temperature?) sensor on the firewall side of the head between the first and second runners of the intake manifold? If the temp guage works that might not be what it is, unless there is one for the guage and one for the computer to calculate fuel map magic. Just my $.02. Good luck.

It could be a coolant temp sensor as well; however, if disconnected your car would fuel as if the engine is at -40F. I was thinking about this the other day and it could also be for an AC pressure switch _or_ intake air temp sensor. I think I'll actually :( go and look at mine and see what I see.

BTW, DRG-- If you don't have hydraulic power steering don't worry about it. The reason you want idle to go up under high PS load conditions is to keep the engine from stalling with the AC on during parking lot maneuvers.

hthy, more info to follow as it comes to mind...

Dustin, you are right, there is a sensor on the head betw. the intake runners; and it is listed as the coolant temp sensor. I am also showing a purge solenoid going on that bracket behind the alternator. I always thought the coolant temp sensor was down on the block, firewall side near the timing cover(I have coolant-y scale on mine). *edit* 1 wire on the one down low; must be for the gauge. (And I'm thinking: seperate sensors on a 2008?) I am going to try and find the power steering pressure switch on mine...

I found my purge solenoid, it is high up on the intake manifold stay bracket. And, it is a red 2-wire connector!
Attachment 6604
Alternator is towards the bottom and photo is taken looking up. HTHY

FWIW, I couldn't find the steering pressure switch on my car. I don't think it has one. I apologize for any confusion caused by my earlier guesswork.

That was it!! Thanks for finding it for me! Once I saw your picture it was obvious once I got back under the car. In just enough of an inconspicuous spot that I couldn't see if without knowing what I was looking for.

Of course a little bad always has to come with some good... now that I have plugged that connector in it wants to randomly stall out when idling? Ran perfect before. Check engine light was on before (and before this whole rebuild) and is still on... I will have to scan and see what codes are coming up. Any ideas?

I think the car is trying to run the evaporitive emissions monitors. I know that is vauge, but read up on it. I'm not sure if the manifold pressure sensor is used to estimate purge flow [in this setup], but in a speed-density car it is used in conjunction with throttle position to estimate the airflow and thus, calculate the injector pulsewidth. HTHY. Sorry you are stalling now :(

Seems to be fine now! Maybe the solenoid was sticking from not being used for a while? Started the next day and it was fine... left it alone for a few more days and it was fine again today. I read they can stick open or closed and cause varying symptoms depending. From what I understand it's an emissions thing... the ecu monitors the fuel line/tank pressure and when it gets to a certain pressure it opens the solenoid and vents it to a charcoal canister instead of the environment.

Still got that check engine light on but so did the previous owner intermittently before any of this happened. Also haven't driven it any considerable distance to give it a chance to reset. My gut tells me it's either the fuel cap not sealing or an o2 sensor. I need to find a good generic scantool program for my laptop/cable. I have the VW program but that's no help on the Chevy lol. Thanks again for all the help!

When I test those, I energize them 25-50 times to make sure they don't stick at all. once will throw a code and two in a row will set a light IIRC.

Dear DRG I am exactly where you were. I got a 2004 Aveo that is on its second engine. One backyard wrench twister was going to swap engines and got started said it was too cold here and went back to eastern Europe. I am left with a semi apart engine in my garage. Went to pick your part pulled a head off another aveo and figured out what parts I would need, finally got the special valve spring compressor from a Suzuki parts counter because GM does not sell them in Canada. The parts so far have been $300 and the tool $169. I did get the all of the gaskets, valves, and guides. I have never done a head job. What were your tricks to removing the valve guides and installing new ones? Did you pull the engine right out and do the work on it on a bench or just pulled the head rebuilt the head and reinstall the rebuilt head? Thanks Rocky

have whatever shop you take it to provide you with not only compression measurements, but have them perform a cylinder leak down test, and that is a better test of weather or not any valves have been bent.

Sent you a PM, but basically we just hammered the old ones out and new ones in with a tool in between so we didn't mash the surface of the old or new ones. Guides were the worst part but mine had to be replaced since they were actually broken from the valves bending. Little chunks from them fell out as we took the bent valves out. Everything else went back together easily. Even putting the collets back on with the spring compressed was easy compared to how I thought it would go. The more I read the more I'm realizing I was pretty lucky with the limited damage that was done on mine considering she was on the highway going about 75mph when it happened. Might be because the plastic idler wheel was the culprit instead of belt snap.

Put 350+ miles on it since the repair and the check engine light is still off. Getting 30+ mpg. Sold to a friend this week since I already have 2 cars and didn't need a 3rd hanging around. He knows the full history of the car so should be interesting seeing how long she goes. I'll be harassing him about a timing belt change in 50-60k miles!

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DRG,
I appreciate the follow up, glad to hear the light is still off. Happy driving :o

What is it with that damnable $2000 price point no matter where you take your car? It's a scam, Chevy KNOWS their engines do this, but they claim there's no problem. Yeah, right!

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Originally Posted by BrokeMom

What is it with that damnable $2000 price point no matter where you take your car? It's a scam, Chevy KNOWS their engines do this, but they claim there's no problem. Yeah, right!

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It's ok if it's out of warranty (tongue-in-cheek). If they designed cars to last longer it wouldn't be cost effective and the general public couldn't afford a car...

Besides, Us mechanics gotta charge something for all the knowledge/experience, schooling, and tools we posess. plus, we have to be able to stand behind our work until the next "service" interval; and to be able to help cover the costs if something does go wrong.

Counter-rant over... :D
DRG is that light still off??

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Originally Posted by BrokeMom

What is it with that damnable $2000 price point no matter where you take your car? It's a scam, Chevy KNOWS their engines do this, but they claim there's no problem. Yeah, right!

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It's 2000 dollars anywhere you go, because it is a very labour intensive job. It's not like replacing a headlight belb...

Congrats on the successful reassembly and the sale of the car! That's what I'm looking for. An Aveo in need of a head and valve job. I miss my first gen Aveo like crazy.

This looks like the most recent timing belt thread. The dealer that sold me my car, which is a local dealer in business for over 30 years, had sold it to/done the maintenance for the prior owners and changed the belt at 60k. He quoted me at $450 for the next change of belt/tensioner/water pump. So far I've only gotten another quote from Midas at ~$550. Anyone know of places in US Indiana that do this and what prices to expect? Thanks.

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Originally Posted by DRG2003

Sent you a PM, but basically we just hammered the old ones out and new ones in with a tool in between so we didn't mash the surface of the old or new ones. Guides were the worst part but mine had to be replaced since they were actually broken from the valves bending. Little chunks from them fell out as we took the bent valves out. Everything else went back together easily. Even putting the collets back on with the spring compressed was easy compared to how I thought it would go. The more I read the more I'm realizing I was pretty lucky with the limited damage that was done on mine considering she was on the highway going about 75mph when it happened. Might be because the plastic idler wheel was the culprit instead of belt snap.

Put 350+ miles on it since the repair and the check engine light is still off. Getting 30+ mpg. Sold to a friend this week since I already have 2 cars and didn't need a 3rd hanging around. He knows the full history of the car so should be interesting seeing how long she goes. I'll be harassing him about a timing belt change in 50-60k miles!

http://www.aveoforum.com/forum/attac...418_141447-jpg

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I am about to do a rebuild or a swap or a repair the head on the 05 Aveo that I have now. How are the bearing doing on that car you fixed the head on and has there been any problems that you know of? I know you sold it to a friend but has he reached that 50000 mile mark with no problems. Thanks

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Originally Posted by 05Aveo

I am about to do a rebuild or a swap or a repair the head on the 05 Aveo that I have now. How are the bearing doing on that car you fixed the head on and has there been any problems that you know of? I know you sold it to a friend but has he reached that 50000 mile mark with no problems. Thanks

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Just a quick update... the Aveo is still going strong! Not sure exactly how many miles he has put on it since... will have to ask... but he is still impressed with the fuel economy.

On a side note... I purchased another Aveo a few weeks ago with the same shattered idler pulley problem... replaced all the valves/guides/seals/etc and she runs! I must be a glutton for punishment... but after doing it once the second time went much faster.

Now start a businesses! Buy broken, fix, sell!

Keep the first gens on the road :D

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Originally Posted by RicochetRandy

Now start a businesses! Buy broken, fix, sell!

Keep the first gens on the road :D

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Now there's an idea!!! :D

Im glad they're both doing well. Best of luck with future projects.

Update on the 05 Aveo. Well the car is still running but has a little chatter at idle but otherwise drives fine. Front of the car wears tires so will have to change the tires and check all the bearings out but has done good for the 500 paid for it and the 500 to 600 put in the engine for it.

05, check the control arm bushings to make sure everything is still snug and not slopping around. My $500 06 fixer had a nasty alignment issue I thought would need lots of work, but just turned out all the ill handling issues were due to the control arm bushings. They are such a cheap fix ($60 bucks for a pair of new arms ready to install) I would suggest checking them before swapping anything else. My LS rig has close to 240K miles so they were shot. I am glad to see I am not the only one reviving these cars when they break! Is the chatter from the AC clutch making noises at idle?

no sounds like lower end on the chatter and I will check the bushings and everything. on it