So my heater core recently went out on me, and it pretty much soaked up my whole interior. I replaced the heater core and put everything back together, and the car ran fine. Recently, my friend and I went on a test drive and the car just died out of nowhere. We tried to start the car, but couldn't hear it priming. Ended up getting the car towed back and a friend of ours was nice enough to let us borrow his spare ECU, just to see if the car would start. Surely enough, the car started. When I opened my ECU, it smelled burnt, but I couldn't make out any burnt areas at all.

My question is, would the coolant be able to fry the ecu? Or do I have a short somewhere that I have to attend to?

Sorry if this has been asked before, but I'm a noob at electrical stuff, and most of the other threads about fried ecus were due a short.

 

Btw, I have a 1994 Integra RS, with a obd1 PR4 ECU. I'm also using a JDM vtec engine harness.

 

so you suspect the ecu

try another ecu and it fixes the problem

what is your question again?

 

Yup, when I opened up the ECU (First thing I checked). It smelled burnt. Didn't look burnt, but I couldn't find the burnt area.

I'm just wondering if the coolant from the heater core leak could short out my ECU. I'm pretty sure I don't have a short anywhere, but I'd never know unless I take my whole interior out and trace the wires.

 

you tried another euc. if you had a short you would have fried it. yes floods are bad for ecus. this seems like a self answering question. you found the problem, know what the fix is. .....what else is there?

 

I just wanted to make sure that floods could short out the ecu before I started tearing everything apart again. Got a little paranoid because I didn't want to blow another ECU before smog again. I guess I'll recheck the wiring after smog just to be safe. Thx for the help anyways man.

 

I just blew my ECU on my all stock 92 GSR. No warning, no heater core issues, nothing. Just up and died. Replaced it and have had no problems. Sometimes parts go out. I wouldn't worry too much about a short or something. At least you dont have my car, its a P61-L00 California emissions OBD1 92-93 GSR ECU. They maybe made 500-800 of these ECUs ever. So yeah it sucks to find one for my car.

 

Oh damn that sucks, can't you use an obd1 P72 ecu?

 

^ im assuming he has a B17A which uses the P61.
If i were you (off topic, sorry) i would take the P61, remove the old circuit board and replace it with a P72 ecu or a chipped board to run a B17. as long as the ecu shell says P61, i see no problem it passing a visual inspection.

 

You can smell a funny burnt smell when a capacitor pops. You could also be smelling a voltage regulator that went bad or a resistor.....the options are countless. Seems as how the ecu got flooded, most likely there were bits of water stored up inbetween two leads of a component creating a short. This could mean too much current was flowing, or there was feedback, or the signal was too noisy if it was bypassing a capacitor which would ruin a component down the line. Or pins on the chips could have shorted....so many options