411 swap did not go well

[FeetDry]

This is my first try at any real tuning. (I've never done any of this before.)
I'm swapping in a 411 PCM into a 2000 S10 2WD Auto (originally had a black box 494 VCM)
I got the wiring diag from LexTech. The 411 came from a 2001 Chev TrailBlazer 4WD.
I double checked the wiring, before doing a full-FLASH. I grabbed "2002 GMC Sonoma 4x2 Truck Automatic L35 4.3 Litre (OS 12212156) LS1_B.tun" from HoldenCrazy.com.
I changed the VIN to match the original 494's VIN. I disabled the Generator F terminal(P1638), set the rear gear ratio(H0103), set the knock sens to resonate(B1402), and disabled the VATS(G1201).

It took a little coaxing to get it stated, but it finally caught. It didn't want to idle below 1000rpm. I kept it there until the coolant got above 160. It through P0300, so I did the CASE. Shut it down and waited. Through it all, the WB AFR stayed in the 12->16 range.

The small problem is, when I read the VIN w/ the V2 it does not give me the VIN that I programmed. I get the old TrailBlazer VIN. The OS ver matches the full-FLASH one that I prog'd.
The big problem is that it is ticking and banging, like it dropped a valve. Is it real mechanical damage or could it be a problem with timing. It happened after firing up after running the CASE. Timing comes from the CKP, right?

I'm trying to figure out if I should swap back to the 494, or tear into the engine. (Yeah, I'm pretty sure it mechanical.)

[Taz]

Hello FeetDry,

Sorry to hear the swap has not gone well. I haven't worked on the 4.3 L V6 very much - mainly remove them to make way for a Gen III conversion. Hopefully someone with V6 tuning experience will jump in - that engine uses a 3x CKP and a CMP sensor on the distributor.

Regarding the VIN - it is stored in the PCM, and I find it often remains unchanged, even after a full (OS & CAL) flash. To change the VIN - connect to the PCM with the V7 Tune Tool. Select the "Flash" menu from the top of the screen ... then select "PCM security" ... a window will open with tabs ... the tab on the right should be "VIN / BCC" this will allow to to change the VIN to the one that matches your vehicle.

Regarding the "ticking & banging" - that may be mechanical, but it can also happen when the timing is way off - have had it happen many times on carbed Gen I with a distributor. It memory serves the valve covers on your V6 are plastic and held in place with 3 bolts in the centre of the covers. The valve cover seals should be rubber - and reusable if not rock hard from age. You may want to remove the valve covers, just to confirm the valve train is indeed intact.

Also, just to keep the thread from taking an unnecessary tangent - by "2001 Chev Trailblazer 4WD", you are obviously referring to an S10 Blazer / S15 Jimmy not a Trailblazer / Envoy (as these use a different PCM).


Regards,
Taz

[FeetDry]

Hello Taz,

I got the VIN issue taken care of. Thanks.

There are no problems showing under the valve covers.

I had a single cyl miss before I ran the CASE, and the banging started after running it. I figure the miss was fuel related. I was seeing AFR's of 12 at low ((1000) RPM. The exhaust smell tells me the CAT was cooking. Is an AFR range of 12 -> 16 for ~20 min OK?

I'd like to clear the CASE table to see if that will have an effect. I'm not sure how to do this though. There is an option to leave the CASE data or clear it in the full-FLASH/CASE window/tab. I'm not sure what this does. It is a checkBox, so I'm thinking it is an option for the full-FLASH operation. i.e. I can't clear the CASE data w/ this window along, I need to do a full-FLASH to do it. But Full-FLASH is grayed out in the V7 Tune window. I'm not sure why. (Suggestions?)

There is no banging w/ just turning it over (no spark), so I'm thinking head/exhaust gasket or it is a timing issue. Any idea how to isolate the timing issue idea? (If I did a full_FLASH will that take me back to before the CASE state?)

Thanks
ML

[FeetDry]

After disconn from the vehicle, full_FLASH is no longer grayed-out. (I'm not sure what is different now.)
I'm going to redo the full-FLASH w/ clear CASE selected, and see what that does. It will take me a few hours to put the valve covers & everything else back on.

Does the OS do anything w/ the VIN? i.e. Does the VIN number do anything to the operation of the PCM?

Thanks,
ML

[Taz]

Glad to hear the valve train looks OK. The VIN is stored in the PCM and does not effect tuning in anyway that I know. I believe the VIN is detected / used by the Scan Tool regarding features / PIDs.

Not a bad idea to full flash the PCM again - and yes - clear the CASE data. Afterward, when you do the CASE with the Scan Tool ensure all required conditions are met - also keep your foot on the brake pedal (brake switch activated) prior to activating the CASE routine, and until after you have completed the routine and turned the key "off".

Best of luck ....


Regards,
Taz

[FeetDry]

The reFLASH did not help the noise problem. The noise is a banging sound which matches the RPM. The banging sound changes to a shreeking sound when it feels like it. It will typically do it when you give it a little throttle. It is loudest at the back around #6 cyl. It is very loud when heard through the bellhousing observation hole.
The sound has me scratching my head. A bad rod bearing at the back? I'm pretty sure #6 is the first stop in the crank oil circuit. The shreeking doesn't make any sense. I have a hard time thinking anything can sheek like that inside a crankcase. Disconnecting #6 spark wire almost seemed to make the knocking worse. (Maybe it was the same.)
Any guess if this could be a cracked flex-plate? I'm thinking about unbolting the torque converter and seeing what that does. I'm not sure if I can seperate the TC & flexplate enough so they don't touch.

I doubt the PCM swap caused this. I think it was the high RPM of the CASE operation. Coincidence,.. bad luck,.. etc.

[nevinsb]

Do you have a log of while it is running? Does your knock sensor have a bolt that runs through it, or does it thread into the engine?

[joecar]

What is your engine's firing order...?

[slows10]

I did a relearn on a 97 4.3 S10 a few months ago. As soon as I let off the heard a shreiking kind of noise. Turns out the passenger side intake gasket blew out and antifreeze went all over the the belts and pulleys. I know its not quite the same as your noise. Seems like these low rpm 4.3 engines dont like that revving procedure during the relearn. Hope you figure it out and their is not much damage.

[nevinsb]

I'm just trying to think of other things that could be wrong. Did you pull the spark plugs out yet? Are they all the same? What do the fuel trims look like on each bank?

[blindawg]

I have hit the Rev limiter many times in my 2000 S10. Everything still holds together... for now. lol.
I would check the flexplate. Also, probably not the cause of it, but check the Dust guard on the Drive shaft... thing. please excuse my lack of termenolgy, for the name of the part excapes me at the moment. It's the support on the shorter piece of the two piece drive shaft. Mine came loose and cause a high pitch noice becasue of the vibrations. Like I said, probably unlikely.

Branden.

[FeetDry]

I have hit the Rev limiter many times in my 2000 S10. Everything still holds together... for now. lol.
I would check the flexplate. Also, probably not the cause of it, but check the Dust guard on the Drive shaft... thing. please excuse my lack of termenolgy, for the name of the part excapes me at the moment. It's the support on the shorter piece of the two piece drive shaft. Mine came loose and cause a high pitch noice becasue of the vibrations. Like I said, probably unlikely.

Branden.

The sound is coming from the back pass side of the engine, or the bell housing. I beleive the dust guard you are refering to is the driveshaft carrier bearing.

[FeetDry]

What is your engine's firing order...?

1 - 6 - 5 - 4 - 3 - 2 These use a reprogrammed distrib cap.

[FeetDry]

Do you have a log of while it is running? Does your knock sensor have a bolt that runs through it, or does it thread into the engine?
It threads into the block behind the distrib cap. B1402 has been set to resonant.

I have a small log from a ~10 min warmup cycle. It is the LS1 sample (default). It has the GM.KR & WB AFR data. Retard due to knock stays at zero. The AFR's are just under 12 to 14. It is mostly in the 13's.

[FeetDry]

I'm just trying to think of other things that could be wrong. Did you pull the spark plugs out yet? Are they all the same? What do the fuel trims look like on each bank?

I have not pulled the plugs yet. I'm trying to avoid that. #6 is a real bear to get to. I don't have the fuel tirm data.

[FeetDry]

Crankshaft speed is twice the camshaft speed.
Does this sound like crank or cam speed to you? (It idles at 600RPM)
The shreiking is not too clear in the audio. It sounds like just another bang.

http://www.youtube.com/watch?v=gn2HPJZABk8
http://www.youtube.com/watch?v=1v-cA5juv9s

The only Knock PID I can find in LS1B is the KnockRetard. Am I missing some?
KR is showing no retard. The knock sensor is just a few inches away from where it is loudest. (And there is no knock retard?)

[Taz]

Listened to both clips several times ... difficult to make an absolute determination ... it sounds like it's a mechanical issue - obviously not positive on that based on a video clip. If it is mechanical - high probability it's a rod bearing. In my experience, rod bearing issues tend to be a "common" problem with the 4.3 L V6.

Hopefully it turns out to be something else ......


Regards,
Taz

[schwoch1]

After listening, I am almost 100% positive that you have a rod knock going on there!!! COuld be wrong, have had several flexplates cracked over the years that sound like rods bearings, but my gut feeling says that it has a rod bearing out!!! How did it run before the swap? Just swapping the PCM wouldnt cause any issues like this!!! Keep us posted!!!

Mike

[FeetDry]

How did it run before the swap? Mike
It ran fine. There was no indication that it was going to let go.

The noise is coming from the back of the engine, it is loudest in the bell housing. But I'm thinking it is banging slower than the crankshaft. So I'll have a look at the rest of the valve train next. If that is not it, then I have to yank the engine to do anything else. I'd like to avoid yanking the engine.
Maybe I'm just trying to make myself believe that it is not a rod bearing.

Thanks

[Taz]

Obviously, do your best to rule out all other options. If you do end up removing the engine it's fairly straight forward. The bolts that secure the transmission to the engine can be a challenge near the body seam. I usually use a 3 foot extension on a universal equipped socket. Once the engine is out, I will generally employ a large hammer to flatten the body seam / reshape the trans tunnel for more easy installation.

The oil pan is a little tight to the cross member. For lack of a better descriptor - the oil pan is a Gen III cast aluminum style pan - and if removed / replaced it needs to be properly aligned with the rear face of the engine block (just like a Gen III).

Hopefully it doesn't come to that ...


Regards,
Taz

[slows10]

I went back thru your thread. I dont see any mention of oil pressure. How is it? If it was something as critical as bearings and making that noise, I would think you might see it in low pressure. You also mentioned some kind of a possible timing issue. Log the vortec cmp pid and see what it is. Maybe something happened to the distributor.

[L31Sleeper]

Um.......automotive stethoscope

http://lh3.googleusercontent.com/public/8pgAJx_qxmBkCsnT8UrjUwWJWex1pPCTOiBzrAmWQawSc1vpz9 pauRxJMR6NeyK4tLG-sXm70GLreML6MFPCuk6gX3e6cbBWuBKQloKlIbDsev77g5T988 vqCOHqEg0dlSVtskflQ3BoYh1r63aTZm2v7XuCzmlAhpKfaiG9 AHjqrcoQDdj5YRQ

[nevinsb]

The top drivers side transmission bolt, I ended up taking a hole saw to the floor boards to get out.

[blindawg]

I beleive the dust guard you are refering to is the driveshaft carrier bearing.
Thats what it was. :doh2: I was laying awake last night and finally it popped into my head.
Dad listened to the video's with me, and he's thinking flex plate. (another person's opinion for what its worth)
I'm hoping thats what it is. $45 part sounds better than a whole new motor. but then again, you could always go bigger. :hihi:

nevinsb: I think they should have holes like that from the factory. :grin: Or just more room.

Good Luck,
Branden

[nevinsb]

I think the carrier bearing is only on the extended cab 2WD models. I was trying to figure out what you all were talking about since I've only owned short cabs. I'm not sure how the drive shaft would make that noise while the transmission is in park. I'm still curious why it would run fine until doing the PCM swap though. Hopefully once you start pulling things apart, you can isolate where the noise is coming from.

My drive shafts just had the rubber dampeners on it. The top one is a short cab long box, the bottom is a short cab short bed. *Cough* note the V2 sitting on the counter :)

http://i172.photobucket.com/albums/w4/nevinsb/DSC02512.jpg

[FeetDry]

I dont see any mention of oil pressure. How is it? Log the vortec cmp pid and see what it is. Maybe something happened to the distributor.

The oil press is low @ idle (~19psi), but jumps up to 40ish on throttle (~1000rpm).
I'm not familure w/ the CMP. That's to say, I'm not sure I've seen one. I'll guess it is on the timing cover. PIDs show a CMPHI & CMPLO. I'm not sure why you need a CMK when you have a CKP.

[FeetDry]

Um.......automotive stethoscope


I have that exact model. It's the neighbors. This is the only way I could tell it was coming from the #6 cyl area. The noise echo's all over the engine bay. It still doen't caompare to the bellhousing noise. (Loud)

[slows10]

Sorry I meant the Camshaft position Retard (vortec) PID.

[slows10]

Rest your hand on the distributor while its running.

[FeetDry]

I think the carrier bearing is only on the extended cab 2WD models.

Yes, it is an ext cab. I wanted to replace the whole assy w/ a single drive shaft a few years back, but I'd need to remove the frame brace. I decided against it.

[FeetDry]

Those firewall bolts are the reason I'm regretting pulling the engine.

Thanks to all for the help.

[nevinsb]

I think the thing that gave me the most grief was the exhaust. There's some pictures on my photobucket page that show me giving some obscene gestures to the transmission crossmember too. The motorcycle jacks work great on the transmission too if you have one.

[FeetDry]

Everything inside the valve galley looks fine. The distrib looks fine. I'm in the middle of yanking the engine.

I'm starting to think about replacement. Should I go w/ a long-block? Go w/ a short-block and freshen the heads locally? Go w/ a GM or aftermarket replacement? I'm just thinking here, but I'd like to hear from people with experience.

The only machine shops I'm finding in my area are racing shops. I doubt I can afford them. I need the vehicle for another couple semesters of school. As usual money is in short supply.

[L31Sleeper]

I GOT AN IDEA !!!!!!

http://www.crateenginesonly.com/ChevySmallBlockV8s/images/cratels2.jpg

[nevinsb]

I don't ever plan on pulling the motor out of mine. If (when) it does nuke, I am getting a LS1, whether it be from a crashed donor car, or in the form of a drivable C5. I'm getting a little sick of putting money into the suspension of this truck and still having poor weight distribution. It moves pretty good in a straight line, but still pushes in corners bad, even though it is a significant improvement over stock.

On a budget, I'd see what kind of price you can find on a crashed truck/van with the 4.3 if you want to keep your truck (I have no idea what kind of work you have had done to your truck if you like it and want to keep your truck), or see if you can find another vehicle for cheap that is already running. I had a 92 ranger which I just sold last summer for $300, and I was looking at other vehicles, like mid 90's Saturns which usually went for around 400 in drivable form.

I haven't yet seen a set of heads damaged by low oil pressure, so you should just be able to get a re-manufactured short block, but keep in mind the gasket sets are not cheap either.

[L31Sleeper]

It moves pretty good in a straight line, but still pushes in corners bad, even though it is a significant improvement over stock.

Move the Battery to the back and put a fuel cell where the spare tire is.

I bet a Aluminum block/head V8 weighs the same as a Iron block/head V6 ??
the problem then will be throttle steer !!!!

[joecar]

Throttle steer is a safety feature... :cucumber::banana:

[ScarabEpic22]

We dont need no stinkin' StabiliTrak or Traction Control! They're for wussies!! :D :cucumber: :rockon:


(That said, ST has saved my butt a few times in the snow...)

And I know Taz mentioned it earlier in this thread, the "TrailBlazer" calibration for 0411 PCMs is a regular Blazer cal and NOT a true TrailBlazer cal. BIG difference, 02-05 TrailBlazers use the P10 PCM and the base engine is the 4.2L I6 DOHC w/VVT engine. Nothing like a 4.3L V6. Just to keep everyone's heads straight down the road! :D

[FeetDry]

#6 rod bearing is basically missing. There is plenty of metal at the bottom of the pan and on the mag plug. The oil filter is pretty heavy.
The intake gasket ports were split on the bottom of the coolant ports. Both dri & pass side. I'm not sure why. Per the GM manual, the manifold was tighten in 3 stages: 40InLbs, 80InLbs, 132InLbs(11FtLbs).
Intake manifold coolant leaks are a common failure on Vortec engines.

If someone knows how to prevent this from happening again, please speak up.

Thanks all for the info/assistance,
ML

[schwoch1]

.
Intake manifold coolant leaks are a common failure on Vortec engines.

If someone knows how to prevent this from happening again, please speak up.

Man, that sucks, I was hoping it was a flexplate, but gut feeling was rod knock!!!

Fel Pro makes a real nice intake gasket that has a stainless steel core with a silicone material bonded to it. I started using that style gasket the minute they came out, and my return rate of intake gaskets refailing after 3 years or so has gone to 0, and I have done ALOT of intake gaskets in 3.1/3.4 V6's and Vortec V6 and V8 engines. Get yourself a set of them after you rebuild the motor and you will never have intake gasket problems again!!!!

Good luck and keep us posted!!!

Mike

[ScarabEpic22]

:( Not good, sorry to hear that. V8 swap time?

[joecar]

#6 rod bearing is basically missing. There is plenty of metal at the bottom of the pan and on the mag plug. The oil filter is pretty heavy.
The intake gasket ports were split on the bottom of the coolant ports. Both dri & pass side. I'm not sure why. Per the GM manual, the manifold was tighten in 3 stages: 40InLbs, 80InLbs, 132InLbs(11FtLbs).
Intake manifold coolant leaks are a common failure on Vortec engines.

If someone knows how to prevent this from happening again, please speak up.

Thanks all for the info/assistance,
MLOuch...

Did the IM gasket failure cause the bearing failure...?

[nevinsb]

+ 1 on the Felpro kit, it is the same one I am running on my truck. Between that and getting rid of the Dexcool, if they hold up under boost, I have no doubt of their ability under vacuum. If you could visibly see splits in the intake manifold gaskets, it probably did cause the rod failure because it doesn't take a whole lot of coolant to ruin the oil. I can't blame GM, because my 3.0L ranger blew 2 head gaskets and cracked a block 1 week after I bought it. It wasn't until I discovered stop-leak I was happy with that truck.

http://i172.photobucket.com/albums/w4/nevinsb/PIC-0056-1.jpg
http://i172.photobucket.com/albums/w4/nevinsb/DSC02600.jpg

[FeetDry]

Did the IM gasket failure cause the bearing failure...?
In my opinion, yes. This is based on the GM service bullit for the Vortec problem. It calls out the internal leak and bearing failure.

I was running Dexcool. I forget if it is all coolants or just Dexcool that ruins bearings. (I have to look into this.)

The failed gasket was a FelPro 95817, which is a plastic printo-seal type. It replace the original GM about a year ago. (Another printo-seal type).

I need to get this repaired fast. The cops showed you yesterday. Apparently it is illegal to have a non-runnig vehicle in my driveway.

[FeetDry]

Fel Pro makes a real nice intake gasket that has a stainless steel core with a silicone material bonded to it.

I found the intake kit that has a Perma Dry Plus deiscription on it. (MS98002T) All I need is the manifold gaskets, not the whole kit. It runs ~$80. I'll be looking for a manifold only P#.

Thanks for the insight. I didn't know they were out there.

[slows10]

Did the oil appear to have water in it?

[slows10]

Illegal for a non-running vehicle in your driveway? Where do you live?

[FeetDry]

Did the oil appear to have water in it?
I have seen the green stuff in the oil. Brown milky sludge looking. This was not that.

I suggest it was not a very bad leak. It did come out milky, but I attribute more of that to the bearing material, rather than Dexcool. It got milky at the bottom of the filter drain. The top was you basic brown oil.

[FeetDry]

Illegal for a non-running vehicle in your driveway? Where do you live? GA They have laws for every aspect of life down here. I find it to be pretty stupid. It is probably illegal for me to be typing this.

[schwoch1]

GA They have laws for every aspect of life down here. I find it to be pretty stupid. It is probably illegal for me to be typing this.
Here in my neck of the woods, they allow you 30 days for non running vehicles, unless your neighbor is some mucky muck in the city, then they tell you to get it out asap!!! I have found that if you make it look like some derilect piece of shit with no motor, they will pick on it. If it looks like nothing happened, IE, not on jackstands, no hood, etc, they will leave you alone. When I lived in Phoenix, my '75 Vega sat in my driveway for 1 year, then one day I put it on jackstands, 3 days later I got the order from the city about inoperable cars... all I did was take it off the jackstands, put the hood back on and everyone left me alone!!!!

Mike

[Taz]

The 20 x 10 portable garage (more like tent) that is popular in the winter in northern areas, comes in handy in your situation. Best $400 I ever spent !


Regards,
Taz

[FeetDry]

Hind-sight & perspective,..
While I'm waiting on parts, I took another look at the bottom end. #5 journal looks very good. Not even a scratch. #6 has been ground down. I figured the crank would be harder than the bearing, but it appears it is the other way around. It appears the bearing has been spinning on the journal for some time. As expected it is pretty beat-up, but it is still whole. The crank jornal has been ground down ~1/16". The metal in the pan looks to be from the crank, more than the bearing.

I originally blamed the failure on coolant in the oil. I'd now suggest the crud coming out of the oil filter was not milky coolant, but rather bearing/crank filing crud. They look similar in color, but not in texture.

A little more than a year ago, the intake gasket burst @ the top-front coolant port. When I pulled it off, I had not drained enough coolant from the system. About a gallon drained from the rear head port into the crankcase. After the gasket was replaced, I replaced the oil. After ~10 miles, I changed the oil again. (Steam from the oil cap showed there was still coolant in the oil.) There was some crud on the mag drain plug. I figured this was the crud from the intake gasket replacement. After 130 miles I replaced the oil & filter. There was plenty of shiney flake coming out of the filter. After 5000 miles another oil change showed metal on the drain plug & plenty of crud coming from the spent filter. I though this may have been a small amount of water in the oil, but now I know it was bearing/crank metal. It lasted another 5 months. Up until the knocking, there wasn't any other sign there was a problem. (Other than there was something going on in the oil.) It had 130K miles on it, but it still ran great, and had good oil pressure. It was one of the tightest engines that I have owned.

I never understood how a bearing could spin in the journal, as it would take a lot to break the locking tab. I'm sure the replacement of the intake gasket caused this. (Another Vortec failure.) I'm not convinced this was caused by coolant in the oil. As in, why would it happen at the first journal in the oil delivery flow? Why would it only happen on one journal? Does the rear-most journal spin bearings more often than other cylinders? I doubt the crud got past the filter as the rest of engine is clean. Is there some other cause of a spun bearing?