Main Relay vs Ecu Question

[reckedracing]

ok, so i've got this 90 hatch, DPFI/auto tranny

the thing has a no run issue

the main relay is clicking as fast a rabbits fuck and the brown top injector (upper injector) is firing off like crazy, in unison with the main relay clicking...

i have a suspicion that the ECU has shit the bed, and that is whats making the injector/main relay click so fast like that
its noticeably loud...

i've changed out the brown top injector with 2 other ones, and i've tried 3 diffrent main relays...
the only other obd0 ecu i have is for a manual hatch, it doesn't do the clicking, but it also doesn't start the car...

ideas?

 

[Z6CRX]

Quoted post[/post]]
ok, so i've got this 90 hatch, DPFI/auto tranny

the thing has a no run issue

the main relay is clicking as fast a rabbits fuck and the brown top injector (upper injector) is firing off like crazy, in unison with the main relay clicking...

i have a suspicion that the ECU has shit the bed, and that is whats making the injector/main relay click so fast like that
its noticeably loud...

i've changed out the brown top injector with 2 other ones, and i've tried 3 diffrent main relays...
the only other obd0 ecu i have is for a manual hatch, it doesn't do the clicking, but it also doesn't start the car...

ideas?

ECU Fuse, and check all your fuses.
My condensor fan fuse crapped out and my car wouldnt start
charged the battery changed the fuse started up

 

[redhothondacrx]

Quoted post[/post]]
ok, so i've got this 90 hatch, DPFI/auto tranny

the thing has a no run issue

the main relay is clicking as fast a rabbits fuck and the brown top injector (upper injector) is firing off like crazy, in unison with the main relay clicking...

i have a suspicion that the ECU has shit the bed, and that is whats making the injector/main relay click so fast like that
its noticeably loud...

i've changed out the brown top injector with 2 other ones, and i've tried 3 diffrent main relays...
the only other obd0 ecu i have is for a manual hatch, it doesn't do the clicking, but it also doesn't start the car...

ideas?

ck all engine ground wires,sounds like a bad connection

 

[reckedracing]

ok, here's an update

i got the helms and found out that the ECU LED flashing 16 times = a fuel injector problem
and i also ran all the main relay tests as per helms and at least one of the 5 main relays i have is good

the helms i have is for MPFI and its saying to listen for injector clicking
well i know the injector is clicking about 300 times a minute so its pointing back to either the ECU or some other electrical problem

i need the helms for DPFI

 

[skillz2k5]

My roomate had the same problem before we converted to MPFI. He pulled an underdash main relay, popped the top off and all the solder points inside were cracked. He heated them up and put a new dot on each one... works fine now. Just something to check not sure if it will fix your prob.

 

[reckedracing]

well, thanks for the reply but i've checked the main relay as per helms step by step diagnostics and it checks out...

 

[handlebarsfsr]

check the map sensor. my relay was messing up and the fuel pump wasnt priming, turned out to be the crappy wiring job i did on my 2.5 bar. theres a fairly large circut, with several sensors on it that causes the relay to kick over like that, one bad wire or sensor on there will make it do that.

 

[yebabee]

I just did a swap for a friend and had the same situation with the clicking, Ended up being a loose ground on the starter. I would look around like the other poster said above for a loose or missing ground.

 

[reckedracing]

the motor has several grounds right off the head and valve cover
we put jumper cables directly from the battery negative to the top ear of the distributor as well as one of the valve cover bolts with no change

we ended up getting another DPFI auto ecu from the junkyard on saturday
as the car sits right now, if you turn it over it will turn over and fire every once in a while, like its only hitting on one cylinder

the new ecu = no hitting at all, and the main relay clicks much faster...

still baffled by this car and its driving me crazy

 

[reckedracing]

well, it turns out that it was the main group of grounds in the engine harness that go to the top of the thermostat housing

apparently the guy who previously owned the car changed the motor and it never started again, becuase he didn't tighten the 10mm bolt...
fucker


thanks for all the replies