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s-10 rattling noise.

09-06-2007, 04:37 PM
97 chevy S-10, 2wd, 2.2L

HERES A VIDEO!!!! you can hear at the end I rev the RPM's up and it sounds fine but when it comes down it starts again.

Frist when my truck would idle with no A/C I would go to start driving and would kind of stall out like it's about to die. I tracked that problem to a bad fuel injector, and replaced the whole injector, and seals. SO that works good now. No stalling when I got to ease out of idle speed.

Now when I just finished getting a new core, new compressor, new accumulator, high pressure line from the core to the condensor, then I charged up my A/C. It worked a week before it quit.

So I went to a buddies house that does A/C for a living, we put maybe a half ounce of this die into my lines. Then we ran it.. THen this Die glows under UV lights and shows you where you AC leaks. We tracked that to the Cycling Switched. We replaced that about two weeks ago.. All A/C works good.


Now when I idle and my A/C's on I have a little knocking noise. A/C disengadged... alls quite. So I'm looking, and seems my Tensioner is knocking back and fourth and making the noise.. So I got buy new a Tensioner. Just replaced that.. Now I start up the truck. and the fucker is still making the noise when it idles.

So I'm thinking my A/C is to full possibly? So I check it out. It's low? WTF? so i put a little mroe in there and gets colder, but still knocking. Maybe my compressor is bad.. It was a eBay refurb.. Damnit.

Now I think my idling speed is to low, and the a/c compressor is to much. SO tourqe the hell out of idling screw. maybe 3 full turns. Nothing. So I put it back where it was. funny thing about my truck is there's not Tach so I have no idea what the idle speed is.

Any Ideas? what it could be. I've heard the knock of death, and it doesn;t sound like a piston.. I'd swear to god it;s tensioner, but obviously it's not. Since i replaced it.

this is what I got in it so far.

Compressor - 119
Core - 300
Accumulator - 40
Filter - 3
AC line - 20
Tensioner - 70
Help from a buddy - A Pizza
Time - Priceless'

I was thinking balancer bolt now, maybe...

09-06-2007, 06:18 PM
New compressors are shipped without oil. Did you add the correct amount of the proper oil?

09-06-2007, 06:43 PM
yeah, I can't recall the exact amount.. Something along the lines of 9oz of PAG 150?!? maybe..

09-06-2007, 07:37 PM
9 ounces of PAG150 is correct for the HS6 compressor. The fact that the noise stops when the A/C is turned off, tells me it's not the A/C clutch or bearing, but possibly the compressor itself. If you have access to a stethoscope, place it on the compressor and listen to it. Another method for isolating noises is to use a piece of 3/8" hose. Put one end at your ear and move the other end around to locate the noise. Rather primative..but it works!

09-06-2007, 10:24 PM
Thanks... it's night now, but i'll try it tomorrow and let you know my findings :)

09-07-2007, 08:07 PM
As far as I can tell it's coming from near the cadallitic(sp?) converter... strange. It starting stuttering at low rpm's agian today.. just as it did with a bad injector, but after looking agian.. all looks good on the injectors.

09-08-2007, 07:27 AM
When the catalyst starts to breaks apart inside the converter, it will rattle. As pieces break away, they can become lodged in such a way that engine performance will suffer. There is no repair, the converter must be replaced, ...if that's the problem.

09-09-2007, 05:07 PM
off of the engine are down pipes from the engine, then there is a break where the converter connects to those. Can I jsut unbolt this and then pull it off.

Can I run it with out the exsausht to see if thtas my problem. Does it use a gasket i'll have to replace when done inspecting.and whats a good convertor look like inside.

Never done exsauhst work

09-09-2007, 07:50 PM
With the converter removed, you'd be hard pressed to hear anything BUT exhaust noise, much less your rattle if it's still there. You'd be better off rapping on the converter with a rubber mallet and listening for the rattle.

How many miles are on the truck, and how recently were the oxygen sensors replaced?

09-12-2007, 10:23 PM
149k, i'd like to say 30,000miles ago for the 02 sensor. near the end of '05

I think my injector is bad again. It's smelling like gas, and rarely it tries to die while sitting at stop light. I got this coming weekend off... looks like I got a project to do.

thanks for your help with this oldie, much appreciated.

09-12-2007, 11:07 PM
sounds like a flexplate to me if it is an auto listen around the belhousing watch this sounds just like yours and does it mostly at idiel i would bet this is it

09-13-2007, 09:48 PM
dude... good catch. looks like a big weekend ahead of me

09-14-2007, 03:57 AM
Sorry for my ignorance, but what is a flexplate?

09-14-2007, 04:52 PM
Sorry for my ignorance, but what is a flexplate?

It is what connects the crank to the converter. also has teeth on it for the starter to engage to. Many people call it a flywheel but in an auto transmission it is called a flexplate

heres a pic of one from a 350 upload%2FCHEVYFLEX.jpg

09-14-2007, 04:54 PM
alot of 2.2 break them

09-15-2007, 03:36 PM
I once had a hamonic balancer make a very similar noise that went away with some revs. The rubber isolators degraded and fell apart.

12-11-2011, 04:33 PM
This may not be applicable, but FYI forum-ers: My 1991 S10 Pickup 2.5L 5-speed had an intermittent rattle that seemed to be coming from under the drivers side floorboard. I was sure the tranny was doing something weird. Turned out to be a heat shield on the top of the front exhaust pipe, just below the manifold mounting. It only had little spot welds holding it on, and they'd broken. It was somewhat formed to the pipe, in a narrow space next to the bottom of the engine (which it was shielding, obviously), so it didn't fall off of its own. I pried it off with a ball joint separator. Rattle gone!

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