ok guys ill try and explain this the best that i can. Last friday i took my car out for the first time in about a week. car started right up no problems and i was drving it for about 10 min when all of the sudden it seemed like it was losing all of its power and it was trying to shut off. I kept it in a low gear and gave it a lot of gas so it wouldnt shut off. Came up to a red light and the tach was jumping like crazy. i put it in gear when the light turned green gave it gas and it just shut off. Try and start it a couple times with no luck. Leave it there over night go back the next day and it starts up( really rough start) Drive it to my mechanic casue i didnt want to mess with it and it barely makes it there when it does the same thing. It seemed once the car warmed up it would start to have theses problems. My mechanic looked at and calls me to tell me that it is my ecu. He says when the car is cold it runs in a "open loop mode" and when it warms up it runs in "closed loop mode" which i guess means what fuel maps it uses i dunno. But he says that its ecu is done for and i need to get a new one to see if thats the only problem. Does this seem like i reasonable problem? I dont see how something like that can go bad all of the sudden. My buddy was telling me there could be a chance thats its the o2 sensor and considering i replaced mine a couple weeks ago when i replaced my headers and downpipe with and old o2 sensor i could see that being the problem. Sorry if that didnt make much sense. Any insight would be great. thanks guys

 

yea its prob the ecu...is the car stock? if you have a fpr check the pressure and make sure your not unloading too much fuel

 

yea i checked the distributor, timing , spark, ignitor...all that good stuff everythign checked out.i mean the car is relatively stock just intake, headers, exhaust, no a/c or p/s but other than that stock.my buddy has an extra p28 laying around i think ill look for a stock h23 basemap a burn a chip and see if that works before i buy another ecu

 

when it dies do you have spark? do you have fuel? these are the things you need to check when it dies. To me it sounds like a main relay...pull the relay and check for burn rings on the circuit board. The relay is under your dash by the steering column

http://techauto.te.funpic.org/mainrelay.php

 

i actually just replaced the main relay a couple months back...i will give it another look though. If the main relay were bad why would it start back up after the engine cools down?

 

yea a chipped 28 will work fine

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pprowler6 &raquo;</TD></TR><TR><TD CLASS="quote">why would it start back up after the engine cools down?</TD></TR></TABLE>

My accord did that, I would stop at the gas station and it would not start back up until it was cooled down. I guess the relay gets hot as well from the high resistance because of the bad solder. I could take the relay out and take it inside in the air conditioning and then plug it back in and it would start. then it would get hot again and wouldnt start. Had a local shop re-solder the original and I havent had any problems.

Good luck!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pprowler6 &raquo;</TD></TR><TR><TD CLASS="quote">i actually just replaced the main relay a couple months back...i will give it another look though. If the main relay were bad why would it start back up after the engine cools down?</TD></TR></TABLE>

Because the soldering on the main relay expands when when it gets hot, this gives
you a bad connection. When it cools down the soldering contracts and gives you a good connection again.

 

Im having the same exact problem with my 93 SI h23 stock automatic

did you ever figured out what was causing the car to die after warm up? could this really be the main relay?