ok i suck at these things
so friday i hit up the drags to try out my new slicks on the way back to the ticket booth i hit a bump car bounced a little and shut off.
towed it home saw i had no spark. the coil plug to the distrubitor was loose hooked it back up and still no start so i had fuel and spark checked out the ecu to see what codes id get. when i removed the cover i found this..

would that part be the cause of no start?
just thought id ask since i do have spark and fuel

its part q34e on a obd1 p72






is this thing replacable also? or should i buy a new ecu...

 

The Q34 SD21780SA transistor is a very common component to burn up.... usually happens when two connectors in the engine bay get switched. Not sure that the IA|T or Purge control circuits would have anything to do with your no start issue though... Could have damaged more circuits on the board.

What does the backside of the board look like?

As long as you didn't burn up/melt or cut any of the traces on the board. That component can be replaced quite easily. It is part number SD21780SA, Moates.net sells them for $2 a piece. probably get one from a local electronics store or online at Digikey as well.

Odd that you have both spark and fuel and still nothing! Did you check to see if you may have jumped a tooth on the timing belt or your distributor may have jolted loose when you hit the bump?

 

damn so should still start??
backside looks ok just those two points of that part that is burnt looks burnt.


id try starting the car to see what codes i get and light just stays green or em i supposed to do something else to get codes??

what happpened full story..


i have a 5th gen prelude same motor h22a but not boosted my daily
and on my 4th gen where this ecu came from the car i raced is boosted.

so i took off my distributor to see if i can swap them from my 5th gen to my 4th gen the one that broke down. but noticed the one on the 5th gen is different. so i put the one on my boosted car ( the one with burnt ecu part) put the distributor back on and noticed it was hard to put on.when i asked my friend to crank it i noticed the distributor would toggle around when he would crank it. so i then took it off and moved 180 degree the part that goes into the cam and it went in easily....

you think maybe that there messed up the distributor?


i unhooked the injector clips to see what happens with i just crank with no fuel and it just cranks. when i put the injector clips sensors back on it cranks and seems like it gets stuck like it wants to start .


i tested compression and all is good i checked timing and its good.

 

Your board is toasted, time to get a new ECU. Not repairable unless you want to spend more money than what it really costs