Testarossa 88 not cranking when hot

Hello, yesterday I went to a place with 100+ F weather the car didn’t crank at all at first try, second attempt fired up right away, later it did it another time.
This morning car started right away
I have never had a non cranking issue, I used to have a cranking not starting issue that was fixed by my mechanic with some wiring to the tachonetric relay.
I read multiple threads about starter, solenoid and relay fixes.
I just want to make sure I attack this very intermittent problem by pinpointing the issue before start replacing parts (WAI 66-9131 or ZM-576 are the latest correct solenoid replacements AFAIK)
I checked my solenoid and I have the original one so maybe it is starting to fail?
For example in this thread post 7 Steve M mentioned “First thing to confirm/deny is if the dash gauges and lights all seem to work OK when the non-start happens”
https://www.ferrarichat.com/forum/threads/ace-electric.106848/

Problem is this only happened in a weather I rarely experience and where I live (colder weather) the car starts right away so replicating it would be complicated.
I would like to start the troubleshooting as a preemptive measure, in case any component is beginning to fail (most likely solenoid is the culprit for what I have read), and I prefer (if possible ) not to add a relay as I enter my car in concourses.
Thank you very much for your help.




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Thanks to Brian and Steve for both replies.
Yes I’ve read all those threads (or most of them) prior to creating a new one. I can see that bypassing and adding the spade connector to the white cable under the expansion tank and also jumping W and Y at the fuse relay panel helps fixing weak connections, but that would not rule out if the solenoid is acting up or if the problem is actually at one of the connections.

If I want to pinpoint where the weakest link is and where the voltage actually drops what would be the game plan?
like start at W then Y then C11 white connector then 50 terminal solenoid?? Something like that?

I assume if voltage is always the same (or almost) through all the chain of command feed then the culprit would be the solenoid??

Steve mentioned 50 terminal at the solenoid should get at least 8-9V minimum and if it does then the problem is the solenoid.

and also should I disconnect the fuel pump relays while doing this connection points voltage tests to avoid unnecessary startups ??

as I said I am just trying to pinpoint the issue that is not really affecting me much as I rarely drive the car to extreme weather places.
Thanks

 

thanks for your response, I checked my fuse panel and it seems my former mechanic was reading your posts because it seems I already have that jumper mod, so I guess my next step is to do the C11 mod Brian suggested.
Is there a way to test the solenoid to rule it out??
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yes it doesn’t look pretty!! But it has been working well for so many years, until yesterday in a very “hot” situation (pun intended).
Here’s better pictures to show you what’s connected to what.
Regarding the fuel pump wire being cut off, I remember he connected them from behind because the white connectors were burnt or something like that, so the smaller gauge brown wires are not for the fuel pumps.
But yes I agree, not the cleanest fix ever

Sorry to ask you again but I really want to know if there’s an easy way to test the solenoid to rule it out, regardless if I improve the connection at C11 and fix this wiring mess, that most certainly I will do to prevent future issues.



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Thanks to everybody
Just to add to this “beating the dead horse” thread and in order to contribute something to the numerous threads about the solenoid and how to find the right part.
I called WAI Global and as stated in other forums the right part is WAI 66-9131 but they don’t sell to the public.
Then I called ZM US office and the person confirmed the right part number to replace BOSCH 0331-303022 is indeed ZM 576.
I asked them for a distributor that could sell to the public and they told me Romaine Electric in WA
https://www.romaineelectric.com/page4.html
called them and they told me they had a location right here in San Diego CA so I called them and luckily they had one in stock.
They just stock it under a different part number SSBO-765 (price $40 out the door)
So I got the new solenoid and I will replace it if after performing the C11 mod Brian suggested I still get hot starting issues, if not I will put if for sale here.
Hopefully this information is helpful, I read numerous threads before posting and it seems this one got all the right information from the experts. Thanks to everybody
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Certainly
here they are
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One thing to mention is that this Fchatter mentioned that he took off the spring as the OEM didn’t have it.
https://www.ferrarichat.com/forum/posts/148073707/
according to the person I talked to at ZM he told me the spring system is to make a better connection,
Also WAI 66-9131 has the same spring system.

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