Hot starting issues

[camguynj]

Originally Posted by SILVER79

What length of wire and type of connectors are needed for the positive post bypass?

Using a 9" 1/0 gauge cable with 1" of each end's insulation stripped off and join each end to the post cable by #1/0 copper split bolts wrapped with two different grades electrical tape should be just fine for a secure insulated permanent connection. See Add Jumper Bypass Cable to underhood positive battery terminal (posts 49 & 55) https://www.camaro5.com/forums/showt...=399658&page=4

[xc_SS/RS]

Sooo I actually may have found the real reason for this issue! On our cars tunes we have a table which has spark advance values to use when starting the car. It's based on coolant temps and something else but I'll screenshot it when I get home.

Either way, it's a table that has start up spark advance values on it. For coolant temps around 170-180 it will give either 3 or 5 degrees advance. But at 190-200 and above coolant temps it'll give either 2 or -10 degrees of spark advance! That big of a swing will screw some stuff up!

So I smoothed my table by changing the -10 degree cells to equal positive values on that row and I'd call it fixed.

You'll see what I mean when you see the table lol

[camguynj]

Originally Posted by xc_SS/RS

Sooo I actually may have found the real reason for this issue! On our cars tunes we have a table which has spark advance values to use when starting the car. It's based on coolant temps and something else but I'll screenshot it when I get home.

Either way, it's a table that has start up spark advance values on it. For coolant temps around 170-180 it will give either 3 or 5 degrees advance. But at 190-200 and above coolant temps it'll give either 2 or -10 degrees of spark advance! That big of a swing will screw some stuff up!

So I smoothed my table by changing the -10 degree cells to equal positive values on that row and I'd call it fixed.

You'll see what I mean when you see the table lol

Very interesting. But I see from your earlier post you didn't experience a hot start problem just a cold start issue so I don't know how this table tune fix is germane to hot start slow cranking. Can you elaborate.

[Benman]

Originally Posted by camguynj

Very interesting. But I see from your earlier post you didn't experience a hot start problem just a cold start issue so I don't know how this table tune fix is germane to hot start slow cranking. Can you elaborate.

The gall dern germans got nuthin to d with it, LOL

[hammdo]

Quote the sheriff:

‘some beech’...

;o)

-Don

[xc_SS/RS]

Originally Posted by camguynj

Very interesting. But I see from your earlier post you didn't experience a hot start problem just a cold start issue so I don't know how this table tune fix is germane to hot start slow cranking. Can you elaborate.

Well, when your engine is trying to start but the timing is at -10 degrees advance it's not gonna want to start well. Move that timing to 2 degrees advance and it'll start much better.

I experienced hot start issues when I first bought my car, but did a few fixes including cleaning ground/positive connection points (point at the starter was green, no copper showing), replacing the starter, making sure factory grounds are touching bare metal, adding a ground to the drivers side of the engine bay, and using a larger grounding strap on the battery. All of those fixes, combined with adding a 160 degree thermostat and switching the fans on sooner kept me closer to positive timing when the engine would try and start while hot. My coolant temps never climb higher than 203 degrees so I wasn't getting into negative timing often during starts. So I rarely experienced a hot start once all of the above was done because of the coolant temp difference.

The stock thermostat won't open until 187 degrees. Normal operating temps with the stock thermostat would be around 205-215+ degrees putting you square in the negative timing start up cells. So you are right that it doesn't help cold starts, but it will make your band-aid for that positive power block under the hood unnecessary (it sounds incredibly ghetto, btw).

See where the heatsoak claims are coming from now? It's not heatsoak, it's barely enough timing advance. I've been going through my timing tables with the intention of smoothing them out to make the car drive better and saw this start up one. Decided to smooth the high temp end of the table (changed -10 cells to 2 or 3) and boom, car starts as you'd expect.

Didn't get a screenshot last night but I'll try and get some today. I can show some datalogs where my timing at start is 0 or negative and then compare it when my timing is positive. I cut the hot start up time in half nearly and it doesn't stumble.

I also increased the start up flare table to help stop the motor revving up high during starts.

Edit: feel free to try this yourself. Drive your car and watch the coolant temps. Stop and start the car for every 20 degree increase in coolant temps and at some point it'll start like shit due to a lack of timing advance.

[Retro69]

Wow! This is quite the revelation ^^^^^

I don’t have my 2011 any longer but I’ll bet this was the cause of my troubles.


Sent from my iPhone using Tapatalk

[camguynj]

Originally Posted by xc_SS/RS

Well, when your engine is trying to start but the timing is at -10 degrees advance it's not gonna want to start well. Move that timing to 2 degrees advance and it'll start much better.

I experienced hot start issues when I first bought my car, but did a few fixes including cleaning ground/positive connection points (point at the starter was green, no copper showing), replacing the starter, making sure factory grounds are touching bare metal, adding a ground to the drivers side of the engine bay, and using a larger grounding strap on the battery. All of those fixes, combined with adding a 160 degree thermostat and switching the fans on sooner kept me closer to positive timing when the engine would try and start while hot. My coolant temps never climb higher than 203 degrees so I wasn't getting into negative timing often during starts. So I rarely experienced a hot start once all of the above was done because of the coolant temp difference.

The stock thermostat won't open until 187 degrees. Normal operating temps with the stock thermostat would be around 205-215+ degrees putting you square in the negative timing start up cells. So you are right that it doesn't help cold starts, but it will make your band-aid for that positive power block under the hood unnecessary (it sounds incredibly ghetto, btw).

See where the heatsoak claims are coming from now? It's not heatsoak, it's barely enough timing advance. I've been going through my timing tables with the intention of smoothing them out to make the car drive better and saw this start up one. Decided to smooth the high temp end of the table (changed -10 cells to 2 or 3) and boom, car starts as you'd expect.

Didn't get a screenshot last night but I'll try and get some today. I can show some datalogs where my timing at start is 0 or negative and then compare it when my timing is positive. I cut the hot start up time in half nearly and it doesn't stumble.

I also increased the start up flare table to help stop the motor revving up high during starts.

Edit: feel free to try this yourself. Drive your car and watch the coolant temps. Stop and start the car for every 20 degree increase in coolant temps and at some point it'll start like shit due to a lack of timing advance.

Thank you for clarifying! I'd be VERY interested in what forum sponsor tuners like Jannety and DynoSteve have to say on this. Wonder if any body with tunes by them have hot start issues?

[christianchevell]

STILL SAYING HOT OR COLD THE POWERMASTER XS TORQUE# 9509 IS KICKING BUTT ON THE STARTING...… AND BEST THING I HAVE FOUND TOTALLY WORTH THE MONEY TO NOT HAVE ISSUES...;;;;;;;;;;;;.AND I HAVE THE ZERO OHM WIRE BYPASS AND THE WORES CHECKED AND GROUNDS WELL......AND A REPLACED STOCK STARTER AT ABOUT 25K...AND NEW BATTERY AROUND THEN ALSO...SO THERE YOU GO ITS ON MY LIST OF MODS NOW BECAUSE I DONT HAVE ROOM FOR THEM ALL IN MY SIG...…..BUT THAT ONE....ROCKS.

AND ITS NOT FRIGGIN ROCKET SCIENCE. AND COSTS ABOUT WHAT THE STOCK P.O.S. COSTS...THAT I NOW HAVE LEFT OVER IN A BOX DAMN NEAR NEW....SELL THAT CRAP SOMEDAY...

NUFF SAID? OR IS EVERYONE GOING TO DELVE INTO THEIR TIMING TABLES FOR SOMETHING THAT COULD ALREADY BE MODIFIED IF YOUR TUNER DID...? MINE DID MODIFY WHAT IT NEEDED.

AND the hotter the engine the car needs that advance when finally running if you ADD some advance it better be when just starting...….

or you instantly have a car running like crap that needs to retard/ advance itself more, the hotter the starter and solenoid the more the resistance to cranking....hot start issue; header heat stroke....

a starter with more torque can help with aftermarket cammed, and or stroked engine, and timing....meh leave it alone, the resistance to cranking from being "Built" does not help........most are not going into their HP tuning, I save that for the expert with dyno. And yes it should get a little more advanced when hot.... retard slows a start, most wont mess with their own timing tables to advance it just for start; or know what to do anyway.

Heat stroke of starters is real...BTW it was real over 40 years ago for me with hot rods just as it is now....there's a reason they make heat wrap, and coat headers, and make aftermarket starters, and heat shields and etc...…. having the stock timing table for starting be crap does not help I am sure, but as I said most are not going to delve into their ECU with Software to deal with a timing issue.....

but easily a aftermarket starter can solve the problem hot or cold to apply much more torque, just clock it right , ditch the stock P.O.S> heat shield and your set...….. should it be zero degrees or 90....

Best recommend I can make like others..... I don't support Jeff Bozos like Avennatti….LOL but here you go folks...…….. https://www.amazon.com/Powermaster-9...gateway&sr=8-1

You have clock it slightly to avoid a sensor coming off the oil pan and bend the main battery cable to the solenoid and buy one ring terminal end...…...AND WALLA...…….. THE PRICE IS LESS THAN STOCK ON THIS ONE...…… TORQUE...… WHAT MOVES YOU.

More resistance to starting comes form a higher lobe cam shaft with stiffer springs making it also harder to crank, add to that maybe higher compression, and a longer stroke and its harder to start; now add in the air temps maybe being real cold or add in heat stroke form the soaking of the starter next to headers that are very close to the starter which stock our starter is like a mini starter.........……………... so this POWERMASTER is actually larger than the stock POS and its a mini starter , and its what us old motorheads called a mini starter and paid $$$$$$$$$$ for back in the day because changing out the stock huge 30 lb 30$ rebuilt Chevy starters was a HUGE PITA annually on OLD MUSCLE CARS and you got to jack it up on one side and slide under there and then practice weight lifting while getting the starter held up and the bolts in and the thing shimmed right...…… been there done that too many times. And nothing like sliding under your car on the side of road or parking lot...….let alone the dang sticking solenoids with the copper contact rings having pitting on them...… UGH bad memories...…...ok take apart the solenoid and turn the ring backwards..and it will last another year...or so....

[xc_SS/RS]

Originally Posted by camguynj

Thank you for clarifying! I'd be VERY interested in what forum sponsor tuners like Jannety and DynoSteve have to say on this. Wonder if any body with tunes by them have hot start issues?

Lol i have had tunes from both and yes it still happened. Dynosteves tune was better because I installed the thermostat when he did my tuning.

[xc_SS/RS]

here are some screenshots to back-up what i am talking about above:

stock cranking advance values:



as you can see for ECTs up to 175 you will get good start up timing and for 176+ it will slowly reduce itself to equal -10 degrees at 100-200 and 250-500 rpms. this is why, when the engine is hot, it will start, stumble, and then catch itself to slowly get into its idle speed/spark settings.

the example i am using is from an E67 ECM/PCM/ECU that you'll find on a 2009 CTS-V (LSA V8):



You can see that at 176 degree ECT the CTS-V has 2 more degrees of timing advance during cranking, and the big one is it goes up to 10 degrees (thats a 20 degree swing in some cells!) for 212-284 degree ECT! huge difference when you compare it to an LS3 tune (camaro, corvette, or even a crate motor tune) and it explains why they start up so well.

onto my adjusted cranking values:



all i did was change the -10 degree values to equal the positive values in their row. starts up great as it is but i think i will add another degree for 176+ cells just to help it a bit more.

here are the graphs:

stock:



cts-v:



mine:



i think it helps, and once i saw the cts-v table i felt pretty confident this is alright to do. keep in mind you will need to adjust the start-up flare table to make sure the engine doesn't rev up like crazy.

christian: i'm sorry but screw your starter. i've got a stock starter powered by a smaller battery than stock and mine cranks like magic.


UUUGE EDIT: because this is a Camaro forum dedicated to the 5th generation model, i present to you: the stock cranking spark values and graph from a 2013 Camaro ZL1 with an A6 trans:

values:


graph:


still think its heatsoak?

[camguynj]

VERY informative ...thanks for taking the effort to post!!! Are the stock cranking advance values shown the actual factory values which were not changed by either the Jannety and DynoSteve tunes?

[xc_SS/RS]

Originally Posted by camguynj

VERY informative ...thanks for taking the effort to post!!! Are the stock cranking advance values shown the actual factory values which were not changed by either the Jannety and DynoSteve tunes?

unchanged and i'm not sure why you think they would change them lol paying 160 for 'tuning' doesn't get much in the way of 'tuning' in my experience.

all Dynosteve changed for me was torque management and fan settings when i had the mods listed in my sig and a Vararam Tune Model intake i had at the time... he didn't touch any other tables within my tune. i also never provided him with a datalog of my tune for him to make adjustments based on. Vararam state (and they're ****ing right) that the intake NEEDS tuning adjustments otherwise the car will not run right. mine never seemed to run perfect on his tune and after doing my own tuning i know why and its because he didn't touch shit.

not sure of what Jannetty changed but i will load that tune and compare if you'd like. highly doubt he did much more than fan settings and torque management as well but i only had an intake at the time so i do not expect much. i didn't provide him with a datalog for the tuning he did on my car as well. he would provide better tunes than dynosteve because you need to buy parts from Jannetty to get tune adjustments. if you don't buy his parts you pay full price for tune changes.

[camguynj]

Just posting this for further discussion as to what is the real cause of hot starting problems?

I believe every forum post about hot starting problems came from cars with LT hdrs, which supports starter heat soak being the cause.

I would think that if the cause was the stock tune cranking advance values that yhe forum would have countless posts of guys without LT hdrs having hot start problems, which doesn't seem to be the case. Taking that into consideration it appears IMO that starter heat soak due to having LT hdrs is the real cause which can be overcome by either adding addtl grounds along with upgrading and/or wrapping the starter, or by changing the cranking advance values.