Hi,

I've posted here a couple times but not in quite a while. Anyway I bought a 1985 Camaro IROC-Z Z28. Red, 5-speed manual, T-Top, carb'd 305 4-barrel V8. Recently had the diff replaced, cost me $1380!! I'm BROKE as hell, in so much debt. I love the car, but now it's giving me trouble again and I'm going nuts.

Since it's carb'd, you're supposed to let it warm up before you start. WHY - can someone give me a real, detailed explanation of why this is? What are the serious consequences to not letting a carb'd chevy V8 warm up before you go?

Today I tried leaving before warming up. It's not particularly cold outside. The engine starts and goes on the choke thing revving between 1800-2300, warming itself up.. I'm in a hurry so i just back out and am about to go.. as soon as I let out the clutch and give it gas to start going, my rpm doesn't go above 500rpm, and the engine is about to die, so I press the clutch back in and it goes back to 1800-2300. I tried going again, same thing.. so finally when i clue in that im not going anywhere, I stop and say fine, let it warm up then ill be ok

WRONG! i hear this flapping kind of noise from the engine, I heard it bfore but only faintly.. now it was much louder and it didn't sound good at all. if i press on the accelerator slightly, it will almost die.. i have to rpess more for it to actually rev more.. if I just barely press the gas, i heard this noise.. like a air-ish noise, as if it's trying to give gas but its not taking it?

so at first I could not even accelerate at all. wtf? finally i was able to, but it sounded and felt like total ***.. normally it's just fine, when i let it warm up.
i didn't have any power, it sounded like garbage, overall really shietty.. so am I in trouble? did i **** up some valves/rings/something?? I dont know much... but I'm paranoid as hell after spending so much on my car, I dont want to have screwed myself over, over some stupid thing like this!

so what do I do? I keep tabs on the oil and coolant regularly., I did the oil change myself and the oil has been fine since.. it leaks coolant but I keep putting more coolant/water as it leaks, until I can replace the radiator (its not the hoses)

i can't afford a new motor or rebuild..

 

it's still doing it this morning... I'm screwed :'(

I don't have the money for repairs or new parts.. gah! should I lease a huyundai till I have more money? :P

but seriously.. any help on this would be appreciated. i know the previous owner beat up on the car quite a bit, but i didn't think i could screw something up this easily

 

that's hard to pin-point from this point.Worst case let a local shop look at it for 65 bucks and go from there.

 

the problem is i've already spent well over $2000 on the car on TOP of the purchase, and I've barely owned the car for a month! argh.. i love camaros but I can't AFFORD that! there's gotta be a better option than a local shop...

 

you spent $1380 to get the differential replaced? i would think you could get a used 4th gen rear end with decent mileage, and possibly better gearing for a lot less than that. its not new, but i would think it would work unless you were dipping below 12s and abusing it, hehe.

 

the previous owner definitely "abused" it... I don't, however. I don't race the car, I have never been to a track, I don't do donuts, etc.. I LIKE my car and I'd like to keep it in nice shape. Unfortunately it's like I touch it and it breaks now... thanks to the last owner.

argh

 

You are suppose to let a carburetored vehicle warm up to allow the oil to lubricate the cylinder walls. The engine runs rich at first and the unburned gasoline washs the oil off the walls. Your supposed to let it run long enough for the oil to heat up a bit. Fuel injected vehicles meter the gas precisely so this is not as necessary.

I am not sure where you are located (I can't see that info. in the topic review below), but in our climate cars will do generally what you describe (minus the flapping noise - does it sound like some kind of pump?) when the heater pipe becomes disconnected from the heat shield on top the manifold, or your air breather temperature valve does not switch over. Your car gets the cold air instead of the hot and the carb freezes up.

This could be a choke or some other sensor issue too, some of these cars are computer controlled carbs, so keep a carefull eye on the automotive technician when he's checking your car out. I have had it twice where I have watched them look my car over for MAP sensers etc. that are only on fuel injected cars. These are rare setups and a lot of guys don't have much experience with them.

If you want to do this cheap, my best advice is head for the local library and start doing some old fashioned research! There might be some newer sites devoted to this, if there is I would appreciate knowing about them as well, but as of a couple years ago these were a pretty rare topic.

 

$1380?! You got ripped... BAD. No way even a full rear end rebuild would have costed that much even with labor. A better choice would have been to find a junkyard rear in good condition and swap that in. Could have had it done for $500 including labor.

As far as heating up the car - it has little to do with oil temp as previously stated. It has to do with the temperature at which the gasoline vaporizes. The engine must be hot for the gas to vaporize, otherwise fuel puddles in the intake and on the intake valves and the car runs really rich. Fuel injected cars still have the same problem but to a much lesser extent as they spray the fuel under high pressure creating a fine mist to begin with. The car will run rough and stumble with the choke on. Most correctly operating QJet chokes pull off at just a little over 100* Try not to drive with the choke on, its not good for the engine and since you obviously don't like it - don't do it.

Once the temp gets just over the 100* mark you should be able to tap the gas and it should idle down to around 1000RPM. Another 20-30* and tap it again and choke should fully pull off and the idle should drop to spec.

I can't diag the noise without hearing it but it sounds like it has something to do with the choke being on. Again, if that's the case, just wait the extra 2-3 minutes for the car to warm up.

PearlWhiteZ28 - the CC QJets do utilize MAP sensors Though they are technically referred to as differential pressure sensors, a backwards MAP sensor of sorts. Try explaining that to a parts guy - been there done that

 

on the price of the rear end. that is going price for labor and new parts! now you got a rear that will go a while and camaro rears are known for failure. on the warm up thing, pearl summed it up.

 

pics

my car's on the left, my friend's RS is on the right


my car from the front...

 

You could lean out the choke a little,especially if you live in a warm climate. The flapping noise could be the trap door thing in the air cleaner snorkle,I have seen then fluxuate and cause that kind of noise. I may be wrong but it's a place to check.

T.

 

on that flapping noise check your exhaust gaskets. it sounds like it may have a leak or possible a cracked exhaust manifold. Just a guess since I can't see it. But look at those and at least be able to rule them out.