teamvalorracing

i see what you're getting at. good idea. but i though he said the tuner ruled all "tuning issues" out?

Black Nugget

It was about the same. I can take a break in about an hour so ill give it a shot at WOT to see how it does.

This issue only occurs after a hot shut down. For example: I drive the car to work, approx 10 miles. On lunch break I attempt to start the car and it hesitates to start. I then drive anywhere and come back to work. I shut the car off, wait a few seconds and then crank. It will fire right up! However, after I shut it off that time when I leave work at the end of the day the car will hesitate to start.
It's only after a hot shut down with a period of time (generally 15+ minutes) before the next find it cranks.



I know that it is nothing in the tune itself. How I know this is that to date the only solution I've found is unbolting the fuel rail and removing the fuel injector from the cylinders after each shut down and then putting them back in when its time to drive again. Everytime I did that it fired right up. Nothing in the tune can replicate that, it has to be something mechanical that I'm overlooking.

teamvalorracing

something must be getting into the cyls and causing this hesitation. i would think it was coolant from the headgasket being warped enough that as the pressure rises in the cooling system from driving, its allowing some to seep past and reside in the cyl's after being shut down causing hard cold starts. if you pull the injectors, its like there is a path for heat and air to evaporate the water/etc from the chambers enough and allow for a decent start.

if you pull the rad cap after its been sitting overnight, is it full to the top? have you ever had to add any coolant?

spectacle

[QUOTE=Black Nugget,Sep 22 2010, 02:51 PM] It was about the same. I can take a break in about an hour so ill give it a shot at WOT to see how it does.

This issue only occurs after a hot shut down. For example: I drive the car to work, approx 10 miles. On lunch break I attempt to start the car and it hesitates to start. I then drive anywhere and come back to work. I shut the car off, wait a few seconds and then crank. It will fire right up!

teamvalorracing

either spectacle is right with the temp table or there is a HGl leak. "internet diag" confirms both. im leaning towards the tune, but thats me.

Black Nugget

When I first noticed the starting issues, back in June after a lot of diagnosing we looked down the cylinders with a boroscope and did see coolant in the cylinders.

Since then the engine has been rebuilt by Inline Pro with only approx 2K miles. Compression check is looking rather solid and I'm making 445whp with only a SC5865 at 22psi with a stock exhaust. I thought about it possibly being coolant leaking into cylinders as it does seem like the coolant level has been getting lower and lower in overflow tank more than of should. But with these compression numbers, power I'm making and only 2k miles on thks motor I can't see it being blown.

I do know my coolant level is rather high. When I leave work tonight ill pop the rad cap and check the level. Then later tonight, after its had some time to cool down ill pop cap again and se to see if the level has dropped! That test answer will be much later, hopefully you will keep an eye on this thread for a response to that.

spectacle

Leakdown would be the only true test of a blown HG though, but checking the coolant level wouldn't hurt in the meantime.

teamvalorracing

well, if his reservoir is getting lower and lower like he says, and a visual inspection of the bay yields no residue or spotting on the garage floor. its going somewhere that it cant be seen. ie, its getting pushed through the motor.

hopefully thats not the case bro, but its either the tune or the gasket. one is causing you grief. if indeed the coolant is getting lower and lower.... i'm calling a slightly blown HG or a "not totally sealed" HG. lol if that makes any sense.

Black Nugget

Oh, I apologize spectacle. You've been very helpful and by no means am I denying your assistance. I'm only adding my input in.

Do you know if anyone in your area might have a Flashpro that would be willing to let you connect your laptop to so you can read and edit calibration? Or any particular screenshots I can post for you?

Black Nugget

I agree. My main question is though, will coolant evaporate? Just for interested parties, if for some reason my head gasket was blown or wasn't sealed properly, is it possible that allowing air to enter the cylinders by removing the injectors after each shut down the coolant that is possibly leaking into the cylinders is being evaporated?

As well, with the engine fully powered down and there being no pressure in the system can coolant pass by? I know last time we determined that was the issue by noticing coolant leaking into the cylinders after doing a leakdown test and putting pressure in the cooling system.