alenpepic

Just out of curiosity has anyone dynod their car with these infamous intake manifold leaks.

I’m currently battling a vacuum leak due to a cracked manifold but I’m not looking for information on fixing the problem. I’m just wondering does the problem cause power loss at full throttle?

Based on my data on HP tuners, I was able to see at Idle the fuel trims were def not perfect but at full throttle I saw some richness which could be from running catless LTH with a stock tune, Ecu correcting the influx of air coming vs the stock headers. But nothing like extremely concerning at full throttle.

Peak spark timing was 26 degrees, and it seemed to be very consistent with no timing being pulled nor knock retard .

I barely drive the car maybe once a week and it’s very old, and tbh the idle issue is so unapparent, I never thought anything of it till I went from the EC V7 tune to oem tune, that’s when it finally threw a lean code.

interesting enough how the EC V7 tune hid that code and this was also something a very experienced mechanic told me about. He was like ohh ur fuel trims are off, watch when u go back to oem tune ur gonna throw that code. Lol gotta love those canned tunes.

eightysixtuned

intake manifold issues do not affect full throttle performance. 26 degree's is less or about than what the factory tune delivers on 92-93 octane. you should be seeing 26-27 degree's. 92-93 octane can see much more timing than that safely.

alenpepic

Thanks for the info, I’ll try another log could also be the winter **** gas we get.


I wanted to fix the problem but it makes more sense to do it in the off season. I know if I tackle it, my car will be out of commission for some time lol.

Are people adding timing to these cars with intake leaks without any issues? My idle fluctuations are so minimal at first ownership I never suspected I had a leak till I saw the idle fuel trims.


Off topic but to add some concerning data.

In terms of knock data I had it off for the eC v7 runs and I was literally hitting only 25 degrees lol so when I switched over to the stock tune I couldn’t tell a difference in power. I’m sure the car was suffering from knock or something else.

But I’m on a stock tune I’m not tied to anyone, this is 100% a fact…. I’ve literally seen a stock c63 run neck at neck with a v7 car and if we are going by my timing data, it says a lot.

eightysixtuned

you would be correct in the statement, if the computer senses non-ideal run conditions, it will limit delivery of ignition timing, thus limiting power if the tune was originally asking for more. this can be a mechanical reason, fuel, or a tune related reason.

skratch77

Do u need a new tb plate? Where is your manifold cracked and your fuel trims will be all over the place if you are running row boxes. Your ecu firmware is not correct and needs euro car firmware on it to fix the trims from bouncing 15 points back and forth at idle.

I recommend a European blackseries firmware and a tune ontop of that but take your row boxes out and see if your trims are good.

alenpepic

I’m on the standard hp tuners 2015 c63 oem tune now

but yeah not a bad idea checking the boxes

I believe their stock tho not the ROW

but I’ve already seen cracks on the outside so it’s leading me to believe that I got intake leak

it’s becoming a big issue on this platform somebody needs to make a aftermarket manifold already.

doesn’t need to be magnesium smh…. I rather have that LS manifold plastic then this garbage