ok so hears the deal you day i was driving along and noticed i weird smell in my 93 del sol... the ecu went into limp mode so i pulled over and pulled up my carpet and smoke was coming out of the ecu... so i drove it home and its been running fine on that ecu still with a slight idle problem and check engine light... with a small burn spot on the circut board and the gold plate on the ecu... so i was like hmmm maybe it was a rare accurance that just randomly happened... so i took the ecu out of my girlfriends 93 integra pluged it in and as soon as i started it, it smoked her ecu... and her car is still running fine with no check engine light but also a slight idle problem... what is causing my del sol to burn up ecu's???

please help!!! my girlfriend is mad at me... lol

del sol specs: jdm d15b, p28ecu, intake, exhaust, battery in trunk, vtec wired in by last owner, etc?

thanks in advance...

 

going to bed bump... please help

 

vtec wire might have a short or your harness might be ripped somwhere. try doing a diagnostic check and count the check engine light blinks

 

its shootin code 1, 9, 41, and another one too but i forget i think its 21... but my vtec still cracks???even with the check engine light on? and all thos codes? idk? i just wanna not blow any more ecu's...

 

actualy going to bed this time bump...

 

Check for a short in the distributor sensor and O2 sensor wires. Any Blown fuses?

 

ive already looked at the o2 sencor wires and they look fine from what i can see... and all the dizzy wires look good too... and no blown fuses!!! its getting frusturating!

 

and what would cause an ecu to do this? just a short? anything else? im going to be working on my car pretty much all day. so ill keep this post open on my computer and check it every once in a while...

 

You are under the wrong impression if you believe that all wire problems can be seen. You must use a multimeter to test the wires for resistance and continuity to body ground.

 

alright so the engine code #9 went away today after cleaning oil out of the dizzy cap but now its saying code #1,#22,and #41. keep in mind it didnt have a check engine light before the ecu went out? what are thos codes? and how to fix them? and could they be the cause of the ecu shorting out...

where do i ckeck the wires from? the o2 censor and at the ECU? or ........... to the ECU??? and how do i know what wire goes where to check them with my meter???

 

man electrical probs can be confusing as ****.. if it where me i might have to bring it somewhere..

 

ya i know man... im just tryin to figure things out before i pay for it to get figured out... plus what can a shop do better then me? they just got better tools. lol but idk? car runs fine so im not stressin bout it right now... im kinda at a dead end... i worked on it all day long!

 

Pics of burnt spot on ECU?

 

hear it is. its on the side where it plugs in by the biggest obd1 plug... as use can see that thing exploded...

anyone know what would make just this spot fry?

 

o im not sure if i mentioned this or not but its a stock P28 ECU thats in the pic... idk if that matters or not

 

going to bed bump... thanks for tryin to help guys... i need to figure this out cuz immabout to boost it within the next month or so......

 

Probably nothing... except fix it, lol

 

That part of the board is for the IAT sensor. Check your wiring.

 

IAT is the Intake Air Temp. right? i thought only obd2 cars had that? this is an obd1 93 del sol... do they have thos? if so where would it be?

you mean the IAC valve (idle air contol valve)

which one? and thank you so much for helping!!!

 

OBDI and OBDII have IAT sensors. It's a 2-wire sensor usually inserted into the intake manifold.

 

Intake Air Temperature. As RonJ said both OBD1 and OBD2 vehicles have it, On OBD1 civics its on the back of the intake manifold, they're usually white.

I did screw up though, Q31 is actually for the evap purge solenoid, usually what happens is someone swaps the IAT and evap purge solenoid plugs, and fries the IAT sensor and fried Q31 on the ECU. check your wiring, and make sure nothing is shorting, rubbing, broken pinched etc. You can replace Q31 btw, but it wont throw a CEL anyway, you just wont have a working evap purge solenoid and may not pass emissions in certain states.

 

^This

Definitely make sure all connectors are plugged into the correct sensors. This is best done by matching wire colors to the sensors.

 

I am only guessing, dont have a wire diagram in front of me, it may be possible that this blown transistor and the circuit that is affected by it may also be affecting the other circuits that are throwing your codes??? Maybe they get power from the same place or are grounded at the same place???

 

alright so i found a plug that was unplugged and switched it with the one that was plugged into the IAT sensor, code 22 went away but code 1 and 41 are still there? did i do it the right way? the picture will show what i did... thanks again for helping out everyone! we are close to figuring it out!!!

 

thats what i was thinking too cuz my car didnt have any check engine lights before my ecu fryed... so idk?