Ok I finally got my car running (for the few that remember a few months ago, it wasn't even starting). I have driven it a couple of time now and have ran into some problems. Let me see if I can list them out and keep it short.

1. Car has a very bad stumble/surge taking off from a dead stop. Sounds and feels similar to a newb trying to take off in their first manual. It feels like I am slipping the clutch out too fast but I know I'm not. Car is also WAY down on power from where I thought it would be.

2. Exhaust note is VERY weird. At idle it sounds nice and deep and exactly how I thought it should.Above that though it sounds like a 4 cylinder almost. Has a very high and very raspy note to it. The exhaust setup right now is just long tubes and open ory NOT the magnaflow thats in my sig. I realize that will be raspy but this is raspier than my good friends LS1 with the same exhaust setup.

3. Car has a weird ticking sound from inside the block. It did it before when the car was just cranking and not starting. IT IS NOT the engine cooling off but thats what it sounds like. Doesn't matter if I actually start the car or just crank it over, still clicks like its cooling off.

4. Speedo won't read above 20mph no matter how fast I am going. I set the tune for stock 3.23 gears (originally an auto car) with 245/50r16 tires but the speedo still isn't right. Is there an easy way to figure out what gears I have without just going through all possible gear combos?

Some important things to note here..The car is on a mostly stock tune I believe that has been converted to SD (didn't have the couplers I needed for the MAF and needed the car running), probably has 3.23 or less gears in it. The power being low and the exhaust note worry me the most as I think (just gut feeling) that they are related. I haven't taken it above 3k rpms yet and not more than 1/4 throttle because I hadn't adjusted the rockers yet (but they now have been).

Any thoughts?

 

Not firing in the correct order or more likely it's misfiring cause a plug is loose. Many people think the misfiring caused by a loose plug sounds like ticking. What they actually hear is the compression leaking past the plug seat.

 

A misfire is exactly what it feels like when I am taking off but after its going it feels smooth, just down on power?

Could a loose plug cause the ticking you are talking about AFTER the car is shut off?

 

To me it sounds like an O2 sensor or header leak, or in my case both. My left O2 sensor was responding to the PCM very slow and didn't have a large range of numbers like it was supposed to, causing the car to run rich. Same with the header leak, unregistered air was getting into the car causing it to once again run rich. Do you smell a hint of raw fuel at all? Im hesitant to call it an ignition problem unless you are getting a misfire and hear it backfire, especially since i was just having the same exact problem right after all my plugs, wires, and opti were changed. After I fixed the header leak and O2 sensor it was fine. Not sure what converted it to SD means?

If you have access to a computer, check for codes and also check the O2 values make sure they are normal, because it won't necessarily throw codes, as mine didn't, since the computer is just trying to make up for all the air it thinks the engine is getting.

 

Well it smells very rich at idle but thats because its an untuned cc306 with pretty much full bolt ons. "Converted to SD" means that I tuned it to run without the map in speed density mode (SD). I do have access to a laptop and the only code I remember it throwing was for my C.A.G.S. not being plugged in.

Thanks for the thoughts though, I hadn't even considered o2s and a leaky set of headers. If I can, Ill check those today.

 

https://www.camaroz28.com/forums/sho...&highlight=maf

My car wasn't throwing any codes for about 3 months and i couldn't figure out what the problem was. Then it had some O2 faults that went away for a while if cleared. Check out the O2 values, make sure they are fluctuating between 10-1000, my left one was stuck around 400 and wasn't fluctuating to much and responding to slow to the PCM.

 

Ok just took the car back out again and tried datalogging with freescan but it didnt work. The program works fine while the car is running but wont save anything for me to look at later?

Anyway back to the posted problems above..

1. Car doesnt stumble or anything if i rev it up enough before I slip the clutch out. Then it takes off fine. Car is VERY VERY low on power. I went wot and it felt NO different than part throttle. Ran it up to 4500 or so and nothing changed. It pulled smooth with no signs of a miss or anything. I looked at the scanning program after the first WOT try and it read something like 40,500 knock count.

2. Exhaust note is still VERY weird. Sounds nothing like a v8 or anything thats even running properly. Still just long tubes and ory with no muffler.

3. Walked inside too fast to listen to the ticking noise. So I am not sure if its still there or not.

4. Speedo went to a max speed of about 22mph even after wot in 2nd and 3rd gears. Perhaps I have maybe 2.73s in it but the RPO code says 3.23s.

Above all, I am VERY VERY concerned with how the car runs and sounds. It is NOT right but I am not sure what to look for.

I did change a couple things in the tune since the last time I posted in this thread. It turned out that the tune was for a 383 but had stock injector sizing so I didn't think twice about it. Changed it back to a 350 and went from there. What I am thinking about doing tomorrow is loading a completely stock tune in it from Brent's Site.

Someone PLEASE PLEASE help me!