I really really really hope someone can rule this out for me but what's the chances of the timing chain slipping or loosening?
2005 Chevy TB LS I6 4.2 starts but stalls 2-3 seconds later
- Thread starter Sean
- Start date
Mounce
Member
That's a good thing. I bought a MAP sensor... I figured if that doesn't correct the problem I'll go ahead and bite the bullet and buy the throttle body. I'll let you know how it goes tomorrow.
SmokeyMcBlazer
Member
- May 5, 2013
- 434
Mooseman
Moderator
Sean asked me to chime in. Not sure if I can really add a whole lot to what's been already said here but I'll try.
All I can really offer is a copy of this document which takes you through the steps of diagnosing a P0068. One interesting thing is that as a diagnostic aid, it says to check the cam sensor circuit for shorts to ground. Unfortunately, some require that the engine be running and need a high end scan tool, probably a Tech 2.
The way you describe the problem, it sounds like a gross air leak somewhere. Could you post a video of when you try and start it? Do you have a buddy that can help you? If so, have him/her keep trying to start it and while it's running for those 2-3 seconds, spray carb cleaner around the intake and vacuum hoses and see if it runs longer. Another thing you could try is blowing smoke into it, like in this video. Maybe tape up the throttle body and use the brake booster hose for the smoke.
https://www.youtube.com/watch?v=zMok2y05jNE
All I can really offer is a copy of this document which takes you through the steps of diagnosing a P0068. One interesting thing is that as a diagnostic aid, it says to check the cam sensor circuit for shorts to ground. Unfortunately, some require that the engine be running and need a high end scan tool, probably a Tech 2.
The way you describe the problem, it sounds like a gross air leak somewhere. Could you post a video of when you try and start it? Do you have a buddy that can help you? If so, have him/her keep trying to start it and while it's running for those 2-3 seconds, spray carb cleaner around the intake and vacuum hoses and see if it runs longer. Another thing you could try is blowing smoke into it, like in this video. Maybe tape up the throttle body and use the brake booster hose for the smoke.
https://www.youtube.com/watch?v=zMok2y05jNE
Thanks Kaitlin... I still have to correctly test the Throttle body and I'll throw the new MAP on it when I get a chance and then I'll see about the Cam. It's never as easy as you'd like it to be. Thanks for joining us Mooseman... I'll post a video of it starting and stalling today as soon as I get over to the vehicle. I'll check more for vacuum leaks.
Bad news guys... I changed the MAP sensor and and the CAM sensor... Same thing. Stared died... Went to the throttle body. Both signals checked out good... Real smooth increase and decrease in resistance when moving the throttle body... I then unbolted the throttle body so that there was a small gap in between the body and the intake cover it bolts too... It started and ran. I gave it a little gas and it picked up but sounded horrible when it did... I then pulled the valve cover... Lobes looked good. Valves clearances were good. The head seemed fine... I then pulled the spark plugs to check them... Who would have thought. The plugs were tightened down way more than 18nm which says it right on the valve cover... 5 and 6 spark plugs were broke off at the tip. Piston 5 has a hole in it. I stuck the magnet straight down to the oil pan. I couldn't find anything with 6. I hate people that can't read and follow simple stupid instructions... So I had mass amounts of blowby when trying to start and when I basically bypassed the throttle body and it was able to suck in enough to compensate for the huge hole in the piston. So next technical conversation... The vehicle has 78k miles on it... It's worth 6k on KBBin fair condition. I can pull the head but my only concern is the timing chain... I've never messed with em. I don't even know how to loosen it. Also theres an A frame that sits under the oil pan... I don't think I can pull the pan unless I remove that A frame... Does anyone knows if you can pull the frame?
BlazingTrails
Member
- Apr 27, 2014
- 19,409
This is terrible news! you can pull the sub frame but with it being 4x4 you are going to have to do a lot of work to get the pan off. If it was me I would just go ahead and pull the engine get it on a stand and inspect it properly. You MAY be able to rebuild it if the damage is not bad to the block and cylinder wall. It is pretty easy to pull the Engine/tranny out of these trucks. probably 2 hours for me.
Only problem is I have no garage. I work on Pearl Harbor which I could do in our shop but they will not let me bring a dead vehicle on base... They consider it a "terrorist act"... My buddy has a scope and we're going to check the liner before we attempt anything... If the liner is damaged I don't know what I'm going to do... If not then we will attempt to pull the pan and change 5 and 6 Pistons. Can you give me some training on the timing chain? If I were to just pull the head is there any shortcuts or tricks or do I have to pull the front half of the engine?
BlazingTrails
Member
- Apr 27, 2014
- 19,409
You will have to remove the timing cover from the front of the engine to completely remove the timing chain from the engine. however if you are wanting to pull the head you can carefully attach bungee cords to the chain to keep tension on the crank gear and just remove the intake cam gear to get the chain off of the head for removal. then when you put it back on just line up your timing marks and slowly turn the engine over by hand to make sure there are no problems before you start it up.
Mounce
Member
Look up Mooseman and look at threads he's posted, he recently did some write-ups for timing chain replacement and oil pan removal without removing the engine. It's not an easy job from how he described it.
BlazingTrails
Member
- Apr 27, 2014
- 19,409
Mooseman ftw!
You can source OEM pistons easily online. Probably eBay is where I would get them.
http://pages.ebay.com/link/?nav=item.view&id=151545656118&alt=web
You can source OEM pistons easily online. Probably eBay is where I would get them.
http://pages.ebay.com/link/?nav=item.view&id=151545656118&alt=web
Thanks guys. We're going to look at the liners tomorrow. Fingers crossed. Hopefully the engine died has soon as it happened and didnt make contact with the liners
Mooseman
Moderator
I would rather run naked into a brick than do the timing chain again. Yes, it's that much of a bitch of a job! Bungee cords won't hold the chain enough. You need either a special wedge tool that will prevent the chain tensioner from popping out or special hook tools that positively holds the chain on both sides. Besides, I think the timing cover also bolts to the head. Actually the chain guide shoes do so it's the full boogie job. And you have to take the pan off, which is the majority of the work. Once that's off, the timing cover is fairly easy unless you get a stuck damper like I did.
How to commit suicide or How to replace I6 timing chain and tensioner.
Articles on how to remove the valve cover and oil pan are in that article.
How to commit suicide or How to replace I6 timing chain and tensioner.
Articles on how to remove the valve cover and oil pan are in that article.
Alright guys... Just pulled the head. Bad bad bad... 5 and 6 valves dropped and it looks like there was never even a piston in 5. The connecting rod is attached to the journal but no sight of a piston anywhere... And no valves were found either... WTF. Someone really did me dirty. Both cylinder liners are shot and the outside of the block is cracked. So onto the next. I found another engine with 90k on it for 1500... I'm not so sure that's a good deal though. Can anyone tell me what engines are compatible with the 05 4.2L I6?
PS thank you all for being so helpful even though I've had nothing but shitty news. I really do appreciate it
PS thank you all for being so helpful even though I've had nothing but shitty news. I really do appreciate it
Mooseman
Moderator
I checked using car-part.com and all it gave me were 2005 engines from similar models. $1500 is a lot but then you are in HI so maybe stuff is more expensive.
IllogicTC
Member
- Dec 30, 2013
- 3,452
1500 in the vehicle itself, 1500 for an engine, you'll still come out gold compared to what KBB states value as...
Good luck, man. If you're looking at engine replacement, I believe grimor has done it, I know there's one or two more around here that have had that joyous experience, so I'm sure we can get you connected to the right people for tips.
Good luck, man. If you're looking at engine replacement, I believe grimor has done it, I know there's one or two more around here that have had that joyous experience, so I'm sure we can get you connected to the right people for tips.
BlazingTrails
Member
- Apr 27, 2014
- 19,409
I just looked on craigslist and I see several engine for under $600. 02-05 will work 2006+ had a different reluctor wheel and they will not work.
Hate to see such a good thread end with a dead engine... I actually replaced my engine instead of replacing the timing chain (jumped time). I have pulled several engines in my day and i am here to tell you, I WILL NEVER PULL ONE OUT OF AN ENVOY!!!! I started the job myself and when I realized that the front axles run through the oil pan and the entire front end has to come apart, I was done. Paid 600 for the engine and 650 to have a mechanic finish pulling and putting it in. Good luck my friend, the book calls for 23-24 hours of labor.Sean said:
ChrisinVictoria
Member
- Apr 26, 2014
- 53
I did a used engine in my driveway over 2 weekends.It may not be a lot of fun but it's been great for a year.There are lots of posts on how to do it and it sounds like you are up to the task. I paid $800 for an engine with 70,000 kilo. on it.Good Luck.
All these damn junkyards want so much for the 4.2L... The block is completely shot though. After another investigation I noticed that the huge gap in 5s liner pretty much went straight through the side of the block. We didn't catch it after pulling the intake cover. Whatever the hell caused it I don't know... Possibly a overheating issue? Spark plugs torqued down too tight? The clearance is awfully close. I'm sure if I pulled the oil pan I could have a better idea but it's pretty much pointless. On a positive note I have 2 good camshafts incase something happens to the next block and the throttle body is still good. Thank God I didn't waste 500 on a new one.
Alright guys... Bought an engine for 600. Guy said it skipped timing... Haha. What an idiot. It was in an accident and the timing chain snapped. I was very hesitant to buy it just because I was scared that when the chain did snap that the pistons could have possibly caught a valve. But I did it and got lucky. Only concern is #3 cylinder has a slight bit of oil on the cylinder wall and on top of the piston. Nothing outrageous... What's the most likely cause for this? I have the head off now (snapped 3 head bolts pulling it, yay) and won't be putting it back on until I figure this out... When it goes into the vehicle it ain't coming back out. I'm thinking bad head gasket but I reckon it could also be the piston rings or the valve seats...
Mooseman
Moderator
Timing chain snapped? I can't see how that would have happened and never heard of it before. These are interference engines so if the engine was running when it snapped, the pistons could have smacked the valves so inspect the valves and valvetrain carefully. For the oil in the cylinder, could have leaked in via a valve just from sitting. Or there could have been some in the plug well and it leaking in when the plug was removed. A compression test would have been an indicator of the health of that cylinder.
Mooseman
Moderator
Alright guys. First of all. Thanks again. You all have been a huge help. I replaced the motor. Before hand I change out a couple of valves on the new head. Slightly bent... I got it in last night but she wasn't running so hot. The shaking for a while and then the derate light comes on and flat on her face she goes. I have a P003 misfire. Changed the coil packs and still have a misfire on 3. Did a compression test on 3 and 0. No compression whatsoever. Took 3 and 4 to TDC and blew into the cylinder and it came out of the throttle body... So I'm pretty sure I have a stuck intake valve. I say "stuck" because if it just wasn't seating correctly wouldn't there still be some kind of compression? So now I ask... Is there anything I can do without having to pull the head off... Again