Hey guys does the Ecu board look normal?

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forcedinduction

move it like this'''''
Joined
Aug 10, 2013
Messages
76
Hi I have been chasing down a problem with no power signal at the pump and no fuel pump prime signal at the pump relay. (The spark and injectors still fire) just no power to the pump or prime.
I have been getting lots of help locally from Dave H. But I can't get there today so I decided to take some pics of the Ecu board.
It looks kinda bad to me because. I really don't know how to describe it. It just does not look right.
But then again I'm brand new to this so I'm not sure what I'm looking at. Lol

Any input would be great.
 

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Looks normal to me too......what does the pins where the car connects to ecm look like....no white or green resisdue?
 
thanks guys. the contacts look pretty unremarkable. I just ordered a new one. I hope that ends this nightmare. sometimes it starts sometimes it does not. but it always starts if I jump the fuel pump.
 
You might have a build up of old dried up dielectric grease in the relay itself. Common problem in our cars. I take it there is no hot wire pump kit on the car correct?
 
no its hotwired. and I replaced the stock relay yesterday. the problem is there is no prime signal from the ecu to the relay. the relay gets standing voltage but no signal to trip the relay to prime the pump when I turn the key. all fuses are good
 
It still does the same thing even if you eliminate the hot wire kit and plug the body harness into the sender the stock way?
 
I had a problem like this 2 months ago. Ended up being the hot wire kit relay was full of rain water because the weatherpack seal was missing on the incoming hot wire.
 
I replaced that relay also. It was corroded. That's how I jump the pump when she won't start. I bought a 5 post relay so I pull the wire out of 87 and plug it into 87a and it sends constant power to the pump so I'm not stuck anywhere. Then I connect it back when I get the car home. But I'm getting sick of doing that. Lol
 
Ive had sensors, and most likely the charcal canister solenoid or egr control module short out and shut down ecm control out puts....
Unplug those two items and test......
If I may suggest more, cause testing a ecu and figuring out is defective can be difficult for me too...but good news is our ecms arent exspensive like the newer cars I work on, can be a costly mistanke for me, so heres some tests I can think of I think you should try to eliminate the car its self....if above doesnt prove a fault.
1)check voltage...at ecu, battery,etc....
2) wiggle test; start car wiggle main ecu wire at battery,main grounds behind pass head.
3)live data, look closely while car wont start, see if any sensor is off....theres a clear flood mode for example if tps is reading wot at start.......
 
forcedinduction, in your third picture, bottom center, see the small transistor with the metal tab and the blue, orange, yellow stripes. Replace it with a PN2907 transistor.

That transistor sends +12 volts to the fuel pump relay to activate it. They go bad all of the time. I posted additional information in another thread here someplace about this.

As for starting at other times, with enough cranking the oil pressure will increase and turn on the fuel pump via an oil pressure switch. It is a back up in the case that this transistor or the relay fails.

RemoveBeforeFlight
 
if the crank position sensor was bad the injectors would not fire either right?
because it will start when I jump the pump everytime.
 
Correct, no injector pulses, there would also be no spark.

If the pump is not priming for 2-seconds at key-on, engine-off, it is a fuel pump relay activation issue. Either that transistor in the ECM is bad, the fuel pump relay or socket is bad, or there is a bad wire someplace. Can re-check for fuel pump prime after at least 10 seconds of key-off (4 -5 seconds actually, but better to be on the safe side).

RemoveBeforeFlight
 
I just replaced the ecu today and everything worked great for a few hours but now its back to its old tricks. im lost lol im about to just run a wire with a switch under that dash to switch the pump on when the car decides to pull this crap-ola. lol
 
I just replaced the ecu today and everything worked great for a few hours but now its back to its old tricks. im lost lol im about to just run a wire with a switch under that dash to switch the pump on when the car decides to pull this crap-ola. lol


I've been thinking of doing the same thing. Mine had a 0psi fuel pressure event on startup a week or so ago.

It just seems like eliminating the relays would simplify things. Plus a switch for the pump would make a great theft deterrent device.

Maybe cut the Hotwire and run it in the car with a heavy toggle..?
 
And all night tonight it primes and starts up with no problem :facepalm: lol

But in the back of your mind you are wondering when the problem will rise again.

I had an intermittent electrical issue last week and a few years ago. In both cases it turned out to be a weather pack that was not clicked/plugged all the way in.

One was a cam sensor plug that looked all the way in,but wasnt. Plus the way it was sitting made it not very visible.

The other was the orange ECM wire behind the battery. The prev owner never clicked it. I hit a bump and ghe car would quit for a second,then be ok.
 
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