Ticking/Clanking noise in the rear?? 1998 S10 has new problems...

[ceremonialdagger]

Hey all!
New to the forum.

I own a 1998 Chevy S10, 4Cyl., 5-Speed manual that just hit 74,000 miles. I've had her since around 40k and loved every mile with very little money put into her along the way...untill now, I fear...

I saw a very silmilar thread regarding a similar problem but started my own anyway in hopes of getting better results...

I've noticed over the past few days a new noise coming from the back of the car that comes and goes while running at a low RPM and only when moving (generally at low speeds) As quoted in the similar thread, "It isnt at any particular speed or rpm, and it seems only to happen when the motor and drivetrain are vibrating at just the right frequency. "

"The noise is a metallic clanging / ticking noise It kind of sounds like that pinging sound that hot exhaust makes after you shut off the car, except it tings in tune with the vibration of the engine."

I initially thought it was an exhaust problem and even thought at first that the sound was my muffler dragging on the ground or somthing loose or whatever but I've been under the car a few times and shook some stuff around and nothing feels loose...

Someone mentioned in the other thread that it could be the catalytic converter? How can I figured that out? I dont know what the cat looks like from under my truck or where it is...

Do other people agree that it sounds like my cat? Is that expensive? What else could it be?

Days after first noticing the ticking problem I'm also noticing that the engine is driving rougher at higher RPMs; it's almost driving like it's an old, worn engine all of a sudden...is this a completely different problem or is it the result of a bad catalytic converter? Should I make a new thread about this problem?

Jesus, I sound maniacal here but I need some help! I dont want to spend a ton of $$ if I dont have to...

Any help is appreciated! Thanks!

[dmbrisket 51]

if its a 98 its verry possible its a cat, the 98 cats are pure junk (trust me i know)replacement cats are expencive oem, and ive seen tonz of aftermarket ones fail, but, i have an aftermarket one on my 98 and it worked out, dont go cheep auto zone crap, get a good magnaflow or equivilant... and yes, the lack of power could be a clogged cat, most bad cats stink like sulfer (rotten eggs) if you have that nasty smell then ide bet money on the cat all the way, one way to check the cat is to literally hit it with a rubber mallot, its the first muffler looken thing after the cross overs, thers one 02 after the cat, and that is the last o2, if im thinking visually correct, the cat is just behind the passengers door

[ceremonialdagger]

How bad is it to drive on it right now? I have to make my last 'long' trip tomorrow (Thursday) evening and am planning on bringing her in for repairs the next day (friday)...

Unfortunately I just recently moved here (Boston) and dont have a good trustworthy mechanic...

[Cam1959]

Originally Posted by ceremonialdagger

How bad is it to drive on it right now? I have to make my last 'long' trip tomorrow (Thursday) evening and am planning on bringing her in for repairs the next day (friday)...

Unfortunately I just recently moved here (Boston) and dont have a good trustworthy mechanic...

I'm not sure but, if it's a partially plugged cat, then I guess the lower you keep the rpm the less exhaust pressure buildup upsetting engine exhaust flow. If very little exhaust flow being allowed thru, I dunno if the cat could blow apart at the seems or not. Maybe have someone rev it while you feel with hand the exhaust, to determine how badly blocked it is ? I never had one so I dunno if banging that cat would help temporarily to loosen some of the carbon buildup blockage.

[reubenator]

Some garages have a heat sensor gun that they can use to read the temperature that your cat is reaching. This is a very sure way to check. Most will do free of charge. If it is your cat, as it gets worse you will find that it will idle fine but begin to cut out as you accelerate. Hills will be your biggest enemy.

[ceremonialdagger]

Its funny because the ticking noise seems to have subsided for the most part and now I'm just running a little rougher when I accelerate...