Hot Start Issues

[camguynj]

Originally Posted by JUSTIFIED

Thank you!! Problem fixed.

As folks read the rest of my reply they should bear in mind that I had significant mods done in late May of 2018, incl. AR headers. The issue began soon thereafter and got worse during the hot Texas Summer.

Prior to mods I always noticed that it was slower than other cars (except for ZL1) to crank over. However, after the mods I noticed it cranking more slowly on hot starts and then during the Summer the problem got much worse (as in click, click, click, crank worse..). I had a new starter installed just as temps were starting to cool down. Seemed to help, but I could tell that it wasn't back to normal.

I had the 2nd ground cable installed about a month ago and and problem fixed. In fact, today it's in the low 70s. I drove the Z fairly hard and oil temp got to 210+ and had zero problem cranking over. We'll see how it does in the Summer heat, but so far, so good.

Glad to hear it!

[jlwdvm]

I have the opposite problem. When the car is cold, it cranks slow prior to firing off.....almost makes you think the battery is dead! It cranks fine when hot at the track.

[FLOW TIE]

Originally Posted by jlwdvm

I have the opposite problem. When the car is cold, it cranks slow prior to firing off.....almost makes you think the battery is dead! It cranks fine when hot at the track.

How old is your Battery?
If it’s cold outside and you haven’t started it for a while it will crank pretty darn slow. You’re in Iowa, I’m guessing it’s colder than a Whitch’s T!!!Y up there..

My battery is now 4 yrs old. When it’s in the 40s here in DFW land, the car cranks pretty slow as well.

I’ll probably replace the battery this spring “Just because”, along w oil change, diff fluid, and my “starting to crack” Trofeos..

When I start modifying, I’ll do the extra ground wire that John (Justified) did.
I’ve seen first hand how well it works..

[serviceguy]

Anybody got details on the 2nd battery ground cable ? part number's?
pics ?

[camguynj]

Originally Posted by serviceguy

Anybody got details on the 2nd battery ground cable ? part number's?
pics ?

see here https://www.camaro5.com/forums/showthread.php?t=504199

[Phemus]

Originally Posted by ca_z28

Can you provide some details regarding where and how you installed the 2nd ground cable? I bought the cables and am ready to install them but I would love to get more info on your install.

Front left side of block, just forward and below header. Other end is on the frame about 6” aft of the block connection. A single 4 gauge ground wire/cable, about 10” long that I put together absolutely FIXED my 2014 supercharged 1LE. Go to Advance Auto Parts and they will cut you a length of 4 gauge wire. Pick up a pack of 2 terminals. Borrow or buy the crimping tool.

I had changed the starter, put a heat jacket on starter, titanium wrap on header near the starter, replaced battery (too soon)…..the slow cranking of hot engine persisted. It ALWAYS cranked slow if within 15 or less after shutting down. No exceptions. When it cranked VERY slow….the “Service Stabiltrak” message came up, No Tach, and No anti-skid. I could not just go out a run a few errands without worrying this was going to happen.

I found the best video on YouTube. When I find it again, I’ll post it.

Video..

[Phemus]

Originally Posted by MrRaZ28

Happens all the time, regardless of temp. Obviously heat makes it worse, but it's the nature of the high compression imo. Probably also due to having a smaller than normal battery for weight savings.

For those who experience the very slow cranking of a hot engine…it has very little to do with the high compression and everything to do with needing a better ground between engine block and the frame. I had the issue for years. Added a single 10” length of 4 gauge ground wire, front left side of block to the frame. Hot engine hard cranking has disappeared.

Here’s the best video….

[void_kp]

thank you for posting the video, in the video you can still hear that the starter motor was weak even after the added ground (yes, the added ground made a HUGE improvement). So it's probably a combination of making sure grounds are good (I've added one back in the trunk to the battery and it helped) and heat shield the starter motor.

those are big displacement engines and I have a feeling that the starter motor wears out quicker than other lower displacement engines. perhaps a stronger starter motor would last longer.

[ariZona28]

I had a hot/slow crank incident a while back. I ran a 19" 4 gauge battery cable from one of the starter mount bolts over to the front subfrane. Got the cable from Autozone. I have yet to put it under similar stress but so far, so good.

[camguynj]

Originally Posted by ariZona28

I had a hot/slow crank incident a while back. I ran a 19" 4 gauge battery cable from one of the starter mount bolts over to the front subfrane. Got the cable from Autozone. I have yet to put it under similar stress but so far, so good.

Sounds promising! Keep us posted how it is in stress conditions. Good luck

[1JEWLDSSRS]

Originally Posted by ariZona28

I had a hot/slow crank incident a while back. I ran a 19" 4 gauge battery cable from one of the starter mount bolts over to the front subfrane. Got the cable from Autozone. I have yet to put it under similar stress but so far, so good.

That's the same cable I used for my "extra" trunk cable, and the one I installed from the bellhousing to the frame, passenger side. Made a big difference in my hot starts, and cold starts.