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b20 vtec turbo overheating on highway

Posted: Fri Jul 04, 2014 10:22 pm
by dmcgrory
on hot days(80+) the ect is over 200F when crusing on highway. 65 mph and over. rpms at 3.7k+. partial throttle. replaced rad with mishimoto full setup(rad, fan, and shroud). even blocked off the ac side to improve airflow to rad. fan never turned off until i gutted the tstat. it does actually turn off now if idling. also the iat are usually above 140F mostly due to sitting in the turbo intake pipe which is directly behind the rad. is there anything in the tune that could help with this issue? or any other suggestions? sorry i cant figure out how to upload my tune but it should be in the vault. any input is greatly appreciated.

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 07, 2014 9:22 am
by Spunkster
ECT of 200 when cruising especially on a hot day is completely normal.

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 07, 2014 11:28 am
by dmcgrory
sorry. within 10 mins of cruising it hits 210 and still rising till i turn on heater or slow down. seems related more to rpms (4k)and throttle% (11-18%)

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 07, 2014 11:41 am
by Spunkster
This does not sound like a tuning related problem as it is more of a physical problem with the setup, improper plumbing, or a mechanical problem. You should have a local shop take a look at it.

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 07, 2014 11:45 am
by dmcgrory
thank u. i will try to make some sort of scoop or something to increase airflow to rad more.

Re: b20 vtec turbo overheating on highway

Posted: Sat Jul 12, 2014 2:41 pm
by dmcgrory
no one can find a physical issue causing this yet. could the ign timing being too advanced at the speed, rpm, ect,and iat cause this? or fuel comps at same settings?

Re: b20 vtec turbo overheating on highway

Posted: Sun Jul 13, 2014 6:52 pm
by AREA876
dmcgrory wrote: i gutted the tstat.
It's best to run a thermostat to control the flow of coolant so the fan can better cool it.

Re: b20 vtec turbo overheating on highway

Posted: Sun Jul 13, 2014 7:11 pm
by dmcgrory
i know its supposed to, but taking it out has been the only thing to help AT ALL. before removing the tstat, the rad fan NEVER shut off. at least now it shuts off at idle and around town. could the iat sensor location be causing ecu to do something that isnt beneficial at cruising speeds? or pcv valve malfunctioning? thank you

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 14, 2014 5:35 am
by AREA876
I suggest you replace the thermostat and set the Override Radiator fan control to 183 deg F and 159 mph

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 14, 2014 10:38 am
by dmcgrory
already have it at 180* and 80mph.

Re: b20 vtec turbo overheating on highway

Posted: Mon Jul 14, 2014 9:05 pm
by keto06
My buddies car has been running 190* override for years now.

Re: b20 vtec turbo overheating on highway

Posted: Tue Jul 15, 2014 1:45 am
by dmcgrory
that means the fan doesnt come on till 190* right? why wait till that high before letting fan come on? what temp does it come on stock?

Re: b20 vtec turbo overheating on highway

Posted: Sat Jul 19, 2014 1:01 am
by dmcgrory
would the iat/ect comp parameters help if i had them set so they dont reduce the fuel(e85) as much at higher temps? theory being that its running too lean at 4k rpm with only 14-20% throttle, and thus raising combustion chamber temp.

Re: b20 vtec turbo overheating on highway

Posted: Thu Nov 09, 2023 11:50 pm
by Maria465
Experiencing overheating issues with my B20 VTEC turbo on the highway. Checked coolant levels, radiator, and thermostat – all seem fine. Considering a high-flow water pump and upgraded radiator. Any other suggestions or insights to address this overheating concern? Thanks.

Re: b20 vtec turbo overheating on highway

Posted: Fri Nov 10, 2023 8:13 am
by keto06
Can you post a datalog and your calibration?