Rattling noise coming from the engine

[Fixxxer]

I'm sure some of you remember that I just spent $1,200 last month for a brand new intake manifold job.Now, 3 weeks after that my 95 Jimmy is making a rattling noise. We took it to the dealer and they LISTENED to it, then called me up and said it would need a brand new engine, the cost would be 4,500. We pretty much told them to go screw themselves because even I know that they were trying to screw me over. It's a 1995 and doesn't even have 95,000 miles on it!

We talked to the service manager and he told me they had given me faulty information. He said it was in great condition, so hee listened to it himself and said there could be crap on the pistons, so he poured some stuff in the engine or something and let it sit overnight then started it up and it was still making the noise. They didn't charge me anything, so I picked it up and took it to a local mechanic that we trust and have been doing business with for years. He listened to it and said it could be need a new crank case(?) or that it could be a cracked piston or could be a control bearing(?). He even said that they could have dropped something in it while they were replacing the intake manifold. After sleeping on it, I gave him the greenlight to take the engine out and look at it to see whats going on inside. I'm waiting to hear from him but does anyone have any idea what it could be?

I was advised not to drive it much but I when I picked it up from the dealer and drove it to the local mechanic (20 minute drive) it ran fine, just made that noise. The noise itself isn't really loud or anything, but it is very noticeable.

If it does need a new engine then wouldn't I be better off just buying a rebuilt engine? Arn't they just as good as a brand new one? Especially since its a 1995. I'm not too smart on cars so any information and insight would be greatly appreciated. Thanks

[amac209]

what i would do is get a low milage engine from a wreck. i assume you have a 4.3l vortec as far as i know the basic engine components have not been changed in the last few years. i'd use the intake and all the sensors& wiring from the shot motor and replace the rear oil seal and maybe oil pump. it just doesn't seem justifiable to spend $4500 on a new motor for a 95. see whats wrong with the old motor first it might've spun a bearing or something. so far i've had good luck with swaping in motors from wrecks. a rebuild is only as good as the place that rebuilt it lots of rebuilds are crap. on lots of cheap rebuilds they reuse old parts or grind them down and put oversize bearings in. whatever you do make sure you get a warrante with it.

[JOEROC]

check the flywheel bolts first,make sure there thight
and does it have a rubber mounted damper pulley
check that out

[cobra1]

this rattle..... is it an all the time rattle, at idle and at speed? or just at 1500-2500 rpm while driving?

[Fixxxer]

Originally Posted by cobra1

this rattle..... is it an all the time rattle, at idle and at speed? or just at 1500-2500 rpm while driving?

you can slightly hear it when it's at idle, but it's much more noticeable and consistent when driving

[cobra1]

go back and ask the people who did the intake job what they used to clean the gasket mating surfaces with.

[pondod]

Did you figure out what the problem is? I am having the exact same thing with my 94 S-10 Blazer. Just replaced the CPI and nut kit, now a rattling noise coming from the motor. Im just looking for some ideas of what mine might be, anyone with help is appreciated! The flywheel bolts are definately tight made sure of that!

[Fixxxer]

I ended up putting a Jasper Remanufactured engine in. So far, so good! Runs top notch

[hcary]

Really? What did the engine and labor run? Sounds like a good option.

[Fixxxer]

Originally Posted by hcary

Really? What did the engine and labor run? Sounds like a good option.

Without going into every little detail, the Jasper remanufactured engine cost $2,064 (36month/75,000mile warranty)

Labor was $1,000 (taking out the old one, cleaning stuff up, replacing certain things, oil change, putting the new engine back in along with some other stuff ect ect)

And then a couple hundred dollars+ for misc. parts/oil/fluids

It was well worth it. This should last me a long long time now.

[MGoBlue102]

So you never found out the noise problem, I had some what of a rattling noise deep inside my old engine, Dealer told me i needed a new engine, I added marvels mystery oil and got one more year out of that engine. I since have replaced with a reman. Got a 3 year, unlimited mileage warranty. Got about 2 years on it now, so far, no engine problems. Just the usual crap that everyone else is dealing with. I paid a little over 2 grand to complete the job. New radiator and water pump to ensure the new engine doesnt crap out too.

[cmattson]

Hello all,

I was browsing old messages & stumbled across this one. Hope you don't mind me drudging up an old topic to share my experience.
I used to own (up until last Dec) a 1996 Chev Blazer. I had the intake manifold gaskets done about 6 months prior -- at the Chev dealership -- to the tune of $1200. I developed a ticking noise in my motor as well, which was then diagnosed as a spun main bearing. At the time, my motor had 84,xxx miles on it. If you do the research, you'll see that the 95's & 96's had a TSB addressing "premature main bearing failure". I'm not saying that's what happened in my case, but it's pretty depressing to put that kind of money into an exquisitely maintained vehicle. While I did use my truck to tow, I followed ALL of the maintenance schedule. I've changed my antifreeze, transmission fluid, and front and rear transmission fluids right per recommendation. I always changed my oil between 3,000-3,500 miles (about 3 months of use for me). I ended up having the GM dealership install a new long block and ended up owning the vehicle for about another year. Overall, my experience with the truck was unpleasantly expensive. I had just about all of the 'routine' repairs done, that I'm sure most of you have already experienced:
- intake manifold replacement
- window regulator replacement
- oil filter supply & return line gaskets replaced

I put thousands of dollars into getting the truck to the point where I sold it. That's horrible! It didn't sour me on GM or Chevrolet. I do realize that the current Blazer was a refreshening of the it's original 1984 model. Most of the stuff in the truck is very, very dated. GM has made a very, very agressive push into improving their vehicles. I ended up buying a new, 2003 Suburbam -- and so far it's been excellent. We'll see how many dependable years it can provide.

My best wishes to all current Blazer owners! I really liked the truck when I wasn't putting money into it.

[bottomtech]

What you guys should have done is take a sample of oil and have it analyzed for gasket material. The 4.3L TBI code Z motor has paper type intake gaskets which glue themselves to the heads. The only way to get it off properly is to scrape at it with a razor blade.
Unfortunately, many techs like to burn them off with 3M roloc discs which turn the gaskets into a fine powder that makes it way into the oil. 3M also made a bristle like pad that goes on a die grinder, which a TSB blamed for original engine failures just after a repair.
Even without using an air tool to remove the gaskets, I still rinse the inside of the motor down and drain the oil, run the engine to burp the coolant then change the oil and filter again.
I'll bet 3/4 of the post intake failures are from gasket debris. The rest are from backwards gaskets, coolant leaks left to go into the oil, or the customer waiting too long and over heating the engine too many times.

[bmfzo6]

i agree with bottomtech. i bet they were not clean when the intake was removed.

[cobra1]

Originally Posted by bottomtech

What you guys should have done is take a sample of oil and have it analyzed for gasket material. The 4.3L TBI code Z motor has paper type intake gaskets which glue themselves to the heads. The only way to get it off properly is to scrape at it with a razor blade.
Unfortunately, many techs like to burn them off with 3M roloc discs which turn the gaskets into a fine powder that makes it way into the oil. 3M also made a bristle like pad that goes on a die grinder, which a TSB blamed for original engine failures just after a repair.
Even without using an air tool to remove the gaskets, I still rinse the inside of the motor down and drain the oil, run the engine to burp the coolant then change the oil and filter again.
I'll bet 3/4 of the post intake failures are from gasket debris. The rest are from backwards gaskets, coolant leaks left to go into the oil, or the customer waiting too long and over heating the engine too many times.

right on the money.....