Hi! I'm new on this Forum and I really need your guys help...
and sorry for the long post..

I've been driving a Camaro 1992 RS 25th anniv. for a month now. Everything ran fine, apart from misc. problems and I made about 600 miles so far. About an hour ago, after cruising the city for 3 hours on low speeds (30-40), I began hearing this hissing sound when I would rev the engine.

On a green light I suddenly found myself having big problems accelerating and the engine was really loud at 40 mph. Also the proverbial Camaro sound (you know, your car sounds like a truck, etc.) is gone, along with all the power. It feels more like a 1.4 V4 Fiat I drove back in Croatia, and is equally loud at very low speeds.

Feeling pretty miserable I drove it back home and, though I was able to get it to go 50 mph, it felt quite bad, acceleration crappy and the engine sounding like it was pulling a 100...

Just before I began writing this post, I went back to the car and started it up. It idled at around 900 RPM and then dropped 500 RPM, went back to 800, anyway idled erraticly and finally it shut off.
I started it up again and revved it a little and it idled steadily at ~900 RPM.
No "SERVICE ENGINE SOON" light or anything.
I revved the engine and it got really loud at 2500 RPM already, and I didn't want to push it further.
Engine oil level is fine. Transmission fluid is a little low.

Car info:

Camaro 1992 RS
305 LO3 V8 TBI
140000 miles

Problem summary: Sudden drop in engine power, feels like a FIAT, engine sounds like a FIAT (no "tractor sound")

What should I do? Change the sparks? Do I have a vacuum leakage?
Distributor cap, wires, rotor problem? EFI dead/broken? Clutch slip?
Fuel filter clogged? A (please *** no ) compression problem?

Recently I used that fuel injector cleaner. I also had some overheating problems because my fan wouldn't turn on; I ended up wiring it directly to the battery, as a temporary solution. The weather was fine today, and the temp. gauge (which is not broken) showed ~180F...

PLEASE HELP, this car is my baby

 

I'd check for vacuum leaks first...especially the hoses running into the TBI. Then check the timing.

Just curious, how is your coolant level?

 

Sounds like a stopped-up cat.

 

Hmm, after the "fan problem" I described earlier, I was constantly checking my coolant level to see what's going to happen.

My coolant level wasn't dropping UNTIL this incident.
I checked my coolant level and it dropped.

It's not disastrous, but it dropped, and the gauge never showed more than 200F (it went to 200 only after I noticed the hissing, but it didn't stay there for long)...

Ironically, this happened only a couple of days before I was about to install open-air w/ ram-scoop, so if it's really a vacuum leak, probably just means I should hurry up with the install

My friend Pat is helping me out a lot and he's trying to make me do stuff to my car that would not make it pass emissions, but if the cat is clogged up, I guess I'll have to go along with his ideas...

How do I check if the cat is clogged up other than replace it and see what happens?

 

I was thinking stopped up cat too. Until I read about the coolant drop anyway. Unbolt the cat and drive a stake through it if it runs better replace it and if it doesn't help it then you have a more serious problem. Cats are pretty cheap. I would advise getting a 3" Catco cat from Summit racing for arount $70 and reduce it down to your 2.5 inch pipe that way you have a bigger cat when you decide to go with a 3" catback or headers into full 3" exhaust like mine. Check your oil just to make sure it is still black and not milky due to water in the oil. Since your car is nearly undriveable keeping a close check on the coolant level may not be possible. I have checked for blown head gaskets by removing the radiator cap on a cold engine and have someone start the engine and watche the fluid in the radiator. It you see air bubbles in the fluid then you may have a blown head gasket. This is only a test and not a 100% proven method.

 

Unbolt the cat and drive a stake through it if it runs better replace it and if it doesn't help it then you have a more serious problem.
this is a pretty drastic way to check. you would ruin the cat, even if it was good.
though i also vote cat, you can pull it off, or drop the exhaust at the manifolds if the bolts arn't rusty.
verify the coolant thing
jess

 

There was no sign of contaminated oil. The loud sound that it was making was coming out of the injectors. I figured that they must have been clogged up and that is probably what caused the car to run pretty lean hence the loss of power and temperature increase. We replaced the injectors with ones from my old 305TBI along with a new fuel filter. We also installed a 14x3 open air element filter since i had one laying around. We also wired in a switch for the fan so that he can control it from the inside of the car. The car runs really good now and has more power. Thanks everyone for your suggestions.
Oh yeah, the cat is next!!!!

 

One more thing to add:
:hail: Pat rules!

 

You can try this method to check a cat to see if its working properly.

Get a meat thermometer and place the point before and after the cat when its warm. There should be a noticeable difference, with the hotter temp being AFTER the cat.

If the temp readings are close (within 20 degrees) then its time to replace that kitty.

Hope this helps.