Ecu? Fuel pump? Wtf!!!

[ryan95eclipse]

Ok so im getting fed up with this damn dsm. but im still keeping it. we all go through it. so i changed a shit ton of parts. got over 2500 tied up in the car just to get it driveable. Changed the water pump oil pump etc. Then rod bearings went out. Changed em today. Found my eagle rods and Je pistons. happy he didnt lie about that. put the car together. im excited. crank it. it starts after a few cranks and im shocked. the rattle was gone when i rev'd it up. now all there is left is a squeaky rattle that sounds liek a throw out bearing when rev'd up. im not too worried about it atm. my problem is. the car has a new ECU brand new. and now its not getting fuel. i reset the ecu. pump kicks on. start it. and it sounds like pure shit and stalls. try again, no fuel pump. i have to basically keep unplugging the ECU to get the fuel pump to kick on and hope it starts. What would be telling my ECU to not turn the fuel pump on and stay on? Please note that someone chopped and speaker wired my obd2 so i gotta manually read the code and i see these number. 12155/12255 ( long blink, two short 1 short wierd pause 1 short 5 short and 5 short then stops) if someone can help id be amazing.

 

[dsmdeliveryboy]

Are you sure your ECU isn't fried?

 

[Jets303]

Just rewire your fuel pump with its own relay and 12v remote. That way you know your fuel pump goes on when you turn the key no matter what the ecu is doing

 

[GsxEcutioner]

My link is telling me "fuel pump circuit malfunction" it would crank over and rough idle and die; sound similiar?

 

[And_44]

There's a few things. When you turn your car to the start position and your starter engages it tells your ECU to turn on fuel pump, when you disengage the starter and the engine is running your CAS then sends a signal telling the ECU to keep the pump going.

Now your ECU and pump have a relay the MPI relay which is located near your ECU. This relay will get the signal from your ECU and then turn on the pump. Any way for your pump to turn on/off goes through this relay via the ECU.

So long story short, I'd suspect your MPI relay. But you said it started the first time and ran like poop, so your Crank angle sensor probally didn't send a signal to keep pump running and you ran the pressure out of your system, and the running like poop, your CAS tells the ECU when to open/close your injectors aswell. Test your CAS or swap it with a known good one.

If your ECU is "new" I'd suspect it last and TEST the other parts first. Of course pulling and checking the ECU wouldn't hurt anything.

 

[Zac692069]

I like this thread I'm learning. Learining is good

 

[GsxEcutioner]

This helps me aswell since i have similiar problems.
-shane

 

[ryan95eclipse]

Well once the first start up started it idled rough then idled normal then after a few minutes it shut off. Tried to start it again and it would start. idle like crazy up to 3000rpm down to 500rpm and all between then die and shut off. its acting like its sputtering for gas and stalls when it does start up. Sometimes when cranking it over itll just stop after the second crank? or not wanna crank at all? It sounds shitty. it backfires and is worrying me. The only way the fuel pump kicks on is when i mess with the ecu. then i have to do that all over again. i checked the relays on the firewall. switched them around. it acted funny then switched them back. Now my battery is starting to die. Im just looking for a few things i should try. I bought it with the guy saying it needs a fuel pump, but that was to rip me off cause it needs rod bearings and over heated. Is there anything i can try to diagnose it?

My obd2 connecter doesnt work at all, The ecu looks brand new not even a scratch on it.

Mpi relay? where is that? i read somewhere it was the gold box next to the ecu? buttt i dont have that gold box on this car.

 

[GsxEcutioner]

Ok for what I gathered on Dsmlink forum and galantvr4. This seems like your fuel pump isn't pumping, The ecu senses a 12v source on one of the pins that controls the fuel pump, if it doesnt see the 12v's, it will toss a code and shut down the car.
-Shane

 

[ryan95eclipse]

will the pump still come on if i pay around with the ecu like it does now? like until it eventually goes out completely? so just change the fuel pump and i should be good correct? sorry i cant reply fast. this site only lets me access it 5 days out of the week

 

[GsxEcutioner]

I got mine to work today, I spliced The fuel pump relay pin on the ecu to another 12v source such as the mpi relay pin, this allows the pump to power up as soon as the car is put on ACC. Much better
-Shane

 

[kidtsi]

Are you sure your ECU isn't fried?

yeah that

 

[ryan95eclipse]

ok sounds good. im gonna try a few things and get some prices on shit. i really wish i would have bought that walrbo pump for 50 bucks when i seen it now. ill kepe and update

Ok so my obd2 doesnt work for some reason. :/ ??? i have no idea why not. and i manually read the codes. and today it was reading just random numbers. the codes i could make out were:
po204
po105
po122
po401
po411
po505
po115


unplugged some sensors n plug em back in and half of them went away.
but still showing random numbers.

its a brand new ecu.
would a different year ecu make my car start(first start of the day) idle for less then 10 minutes and a hard stall? then not wanna start at all without back firing and making other noises? im pretty sure my fuel pump is fine. it kicks on but the continuous trying to start my car is killing my battery quickly. and today after it kept stalling/not starting. a little bit of white smoke started coming from the exhaust. not much just a little bit which i think if from it sitting. any ideas? im just trying to get this car driveable. its been in my driveway for 3 months. since i bought it