Extreme overheat incident! - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Jsvine · 05-20-2020, 08:55 PM

So yesterday I went to warm up my car with my electric fans off, per usual because I removed my thermostat. I had went inside my house to do something then got distracted and took longer than I had anticipated. When I had returned to my car the oil temp was around 150 Celsius which is ~300f (this is the highest temp I?ve ever heard of or seen a SR20DET reach). So I turned off my car and let it cool down to around 90 Celsius which is ~200f and refilled the coolant because it had all evaporated (the radiator pressure cap did not release but all my coolant was gone and no sign of coolant on the ground). Now after this event I have a backfire/misfire issue above 4k. What could overheating to that temp have damaged to cause this misfire issue?

Kingtal0n · 05-20-2020, 11:25 PM

compression test look for bad Head gasket

check the wiring and electronics around and on the engine for burnt/crispy/melted

The high temp may have fried an electronic or blown the head gasket

Change the oil asap, heating it that high may have ruined it

post pictures of the plugs, and when you do the compression test use 2 different testers if the first one gives a bad result. Also write the numbers down to the nearest decimal. 145.5PSI for example.

Jsvine · 05-20-2020, 11:49 PM

Thank you! I will do that when I get home today👍

jedi03 · 05-21-2020, 08:01 AM

GL...i accidentally overheated one of my sr's when fan wiring fried...only went to 250F thankfully but no damage was done, also thankfully!

*brndck* · 05-21-2020, 08:25 AM

Quote:

Originally Posted by Jsvine

(the radiator pressure cap did not release but all my coolant was gone and no sign of coolant on the ground). Now after this event I have a backfire/misfire issue above 4k. What could overheating to that temp have damaged to cause this misfire issue?

how do you know it didn't release? at that temp it would all be steam anyways.

1: if your head gasket DIDN'T blow i'd be amazed
2: check your oil for coolant contamination and vice versa
3: you may have done damage to coilpacks with that level of heat.

Jsvine · 05-23-2020, 02:31 AM

Found the issue! 2 coil packs had cracked

. Thank you for your help!

05-20-2020, 08:55 PM	#1
Jsvine Join Date: May 2020 Location: California Age: 25 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Extreme overheat incident! So yesterday I went to warm up my car with my electric fans off, per usual because I removed my thermostat. I had went inside my house to do something then got distracted and took longer than I had anticipated. When I had returned to my car the oil temp was around 150 Celsius which is ~300f (this is the highest temp I?ve ever heard of or seen a SR20DET reach). So I turned off my car and let it cool down to around 90 Celsius which is ~200f and refilled the coolant because it had all evaporated (the radiator pressure cap did not release but all my coolant was gone and no sign of coolant on the ground). Now after this event I have a backfire/misfire issue above 4k. What could overheating to that temp have damaged to cause this misfire issue?

05-23-2020, 02:31 AM	#6
Jsvine Join Date: May 2020 Location: California Age: 25 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Found the issue! 2 coil packs had cracked. Thank you for your help!

05-20-2020, 11:25 PM	#2
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,828 Trader Rating: (17) Feedback Score: 17 reviews	compression test look for bad Head gasket check the wiring and electronics around and on the engine for burnt/crispy/melted The high temp may have fried an electronic or blown the head gasket Change the oil asap, heating it that high may have ruined it post pictures of the plugs, and when you do the compression test use 2 different testers if the first one gives a bad result. Also write the numbers down to the nearest decimal. 145.5PSI for example.

05-20-2020, 11:49 PM	#3
Jsvine Join Date: May 2020 Location: California Age: 25 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Thank you! I will do that when I get home today👍

05-21-2020, 08:01 AM	#4
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,836 Trader Rating: (8) Feedback Score: 8 reviews	GL...i accidentally overheated one of my sr's when fan wiring fried...only went to 250F thankfully but no damage was done, also thankfully!