Thread: VS cam project almost finished, a couple of questions

Update! Car is running smooth, ticking in engine has gone away, engine is building oil pressure 50psi, which seems a little high, but oil is getting to the engine. Smoking has gone away, was the headers. She sounds good! I'll post some result videos. Thanks for crossing your fingers guys.

Sorry about the quality, it's from my Galaxy S3, but here's a video of it running! The video makes it sound like the headers aren't properly installed, but the engine bay sounds nothing like that in person. Notice one area the tone is deafened, then in another, you can hear nothing but the exhaust.

https://www.youtube.com/watch?v=91SME2gcnqM

While scanning, I noticed I am still getting misfires here and there.. They aren't audible, but my counter increments, then resets, and repeats, for two cylinders. Also, my LTFT is pegged at 14.6 and I saw on another thread in this forum that is a good indicator of a vacuum leak??

Originally Posted by REDCOMPG

Awesome so more importantly have you taken it for a ride? Obviously it's snowing so I don't expect you to drive it to hard. I'm sure you'll love the setup I know I love mine.

Thanks! I haven't taken it for a true ride, the exhaust is so deafening I can't listen for anything that doesn't sound right up front. I did go around the block a few times and the response seemed a little groggy. Like I said though, I could barely get on it because any bit into the pedal and the whole cabin is the resonator.

Originally Posted by Scottydoggs

get the cat back back it already lol

spray some carb cleaner at the vac lines and sensors, if the idle jumps you found the leak area.

Is it a leak for sure if my LTFT shows that high of a trim?

Originally Posted by machinegunsquid

Get the cat-back on first. Make sure the 02 sensors are installed and plugged in.

Did you let the car warm up to operating temp? Once it's up to temp see if your LTFTs are still pegged.


If they are, start hunting for a vacuum leak.

I'm running no catalytic converter so I removed the rear o2. The front one reads about 0.3 to 0.6 most of the time, bouncing around periodically, and spiking to 1 when I tap the pedal a bit.

I did let the car warm up enough to get the cabin warm, and it still said 14.6 so I guess I have a vacuum leak.


Quick question though, I noticed when I was driving it around the block, it is not as powerful as it used to be at low end. Is that because of the headers and downpipe have alot more flow or because it's not tuned or a combination of both?

Hmm. So I started the car and let it get warm while scanning, and I noticed the front half of the engine (1 3 5) are all misfiring randomly. Not throwing any codes though.

Also, when I revved the engine, the LTFT would go way down, then very slowly climb its way back up to 16-17, even when the car is still idling.

Originally Posted by REDCOMPG

Your uh wires are in the right place right? Hmm misfiring any chance do you have a spare ICM ? I had some misfire issues before and ended up being that the ICM was bad.

Yeah all of the wires are in the correct places. New autolite 104s in all cylinders and new wires. I don't have a spare ICM.. But if the ICM is bad, why would only one side of the engine give issues?

Did some more digging, still not sure what the problem is.. After running for 10-15 minutes, the obd reader counted 6 misfires on 1, 200 on 3, and 1500 on 5. No misfires on 2 4 or 6. I'm led to believe the intake manifold is leaking in the front right corner..

Yeah the plugs are definitely right. 3 and 5 being switched caused popping on the very first start and switching those two fixed that. I'll try moving the coil packs around tomorrow. Is there anything you could think of that would cause only one side of the engine to misfire like this? Leaking EGR? Leaking crossover pipe? Certain vacuum hoses? I am stumped on the scenario.. The front head did come off, but I find it weird that cylinder 5 misfires 250x more often than cylinder 1..I am also going to try a compression test on the front cylinders tomorrow.

Hmm. While I haven't ruled out the intake manifold leaking, I think the problem may actually be fuel related. If I am correct, cylinders 1 3 and 5 in that order are the last to get fuel. My schrader valve on my fuel rails is very slowly leaking fuel, would that be an indicator of insufficient fuel pressure? I am going to get yet another pressure gauge today to check to see if cylinder 5 is maybe getting scraps for fuel.