engine won´t start when hot - problem solved

[camguynj]

Originally Posted by caper

Ok this isn't a header issue. I have had the same issue for years now and have tried everything. Positive cable bypass, new starter, new crank sensor. Multiple batteries, new ground wire. Starter heat shield... now engine is being rebuilt and a new power wire put in under engine to starter. None of those solved the issue. All worked better for a short time then the issue came back. Sooooooo what's the actual solution? I don't know.

Seeing that you addressed the usual suspects only thing I can think of is to measure the volts at both the neg engine block and engine bay positive post during a HOT startup. If they measure below 12.6v measure trunk battery voltage. If ok check trunk ground. If ok maybe add another ground directly to where the starter bolts to the engine block.

[MS7]

Originally Posted by camguynj

Between 12.4 - 15+ while driving based on charging requirements with 14.6-14.9 being around the norm. See this thread for in-depth info https://www.camaro5.com/forums/showt...reduce+voltage

my voltage now when the key off 11.9. when on 11.4
im using sct x4 to read the voltage.now even my sct x4 not working well due the low voltage under 12.
sct support they told me you have voltage issue
and advice me to unplug an accessories on the car like phone charger or any things take the voltage down.

[camguynj]

Originally Posted by MS7

my voltage now when the key off 11.9. when on 11.4
im using sct x4 to read the voltage.now even my sct x4 not working well due the low voltage under 12.
sct support they told me you have voltage issue
and advice me to unplug an accessories on the car like phone charger or any things take the voltage down.

Those voltage readings means your battery is dead

[MS7]

Originally Posted by camguynj

Those voltage readings means your battery is dead

yeah it was dead i replace it with new one.

i found this device in you tube it my fix the issue

MAGA RAIZIN Voltage Stabilizer

[Ihab]

https://youtu.be/wvb92REaRSc works great now

[Jesmid]

Originally Posted by OnkelMatze

I just talked with my mechanic, he says the second cable at the chassis frame is directed to a control module

any contact at the chassis works fine for that additional cable, best place is where a screw already exists

So that wire runs from a control module to the frame, not from the block to the frame? Can you give details on the control module hookup, if that's indeed what it is?

[Joker.bmf]

Im trying to figure out where this is located at

[SneakySS]

I added a 2nd engine ground

[JooktheSnooke]

Originally Posted by SneakySS

I added a 2nd engine ground

did that solve the problem? im having the same issue where the motor wont turn over when hot. what size bolt is used?

[R1jamn]

Originally Posted by JooktheSnooke

did that solve the problem? im having the same issue where the motor wont turn over when hot. what size bolt is used?

I have a ZL1 and the threaded hole is a 10mm x 1.5mm.
You can use a 20mm length bolt or if you use washers then you can use a 25mm length bolt.

Another member stated his was a 3/8 dia. bolt with fine threads. This would be a 3/8-24.
I tried a 3/8-24 bolt and it was not going in.
I tried a 3/8-16 bolt and it would not thread in all the way because the pitch of the bolt and the threaded hole did not match and it was very loose.
I converted the closest size to a 3/8-16 and came up with a 10mm x 1.5 bolt and it threaded in perfectly.

BTW....I used a stainless steel bolt and lock washer.

[CJ27]

Originally Posted by R1jamn

I have a ZL1 and the threaded hole is a 10mm x 1.5mm.
You can use a 20mm length bolt or if you use washers then you can use a 25mm length bolt.

Another member stated his was a 3/8 dia. bolt with fine threads. This would be a 3/8-24.
I tried a 3/8-24 bolt and it was not going in.
I tried a 3/8-16 bolt and it would not thread in all the way because the pitch of the bolt and the threaded hole did not match and it was very loose.
I converted the closest size to a 3/8-16 and came up with a 10mm x 1.5 bolt and it threaded in perfectly.

BTW....I used a stainless steel bolt and lock washer.

Very helpful ty. Still think it needs a more cranking amp battery but seemed to help.

[Pro Stock John]

Bump, interesting conversation.

I have been wiring my other car, so this would be easy to do and try.

[CJ27]

Originally Posted by Pro Stock John

Bump, interesting conversation.

I have been wiring my other car, so this would be easy to do and try.

I ran a 2 guage from the battery up to the pass side where the engine is grounded and put 2 guage 2nd ground on the drivers side. Still had the heat soak issue. Maybe use 0 guage. Going to a agm interstate battery did actually seem to improve it.

[camguynj]

Originally Posted by CJ27

I ran a 2 guage from the battery up to the pass side where the engine is grounded and put 2 guage 2nd ground on the drivers side. Still had the heat soak issue. Maybe use 0 guage. Going to a agm interstate battery did actually seem to improve it.

You may want to try adding a Bypass Cable to the underhood positive battery terminal see posts 49 & 55 in this thread https://www.camaro5.com/forums/showt...=399658&page=4
This resolved the starter heat soak hot start problem for almost every guy who still had the problem after having already added a 2nd ground and replacing the battery & starter.

Use a 9" 1/0 gauge cable with 1" of each end's insulation stripped off, then join each end to the post cable using a #1/0 copper split bolt. You also need to strip some insulation from each side of the post cable where they’ll join. Then wrap each end split bolt connection with two different grades electrical tape for a secure insulated permanent connection. Don’t forget to DISCONNECT THE TRUNK NEGATIVE CABLE FIRST !!!

See post 64 in this thread for an explanation of why this provides more power to the starter https://www.camaro5.com/forums/showt...g#post10107568