ABY ECU Intermittent issue

[edge_devil]

I've kept the fuel pump wiring as standard, with the feed being switched by the ecu controlled relay. I think I need to check some wiring, especially as you say the grounds and now I think the relay too!

Fuses are standard blade, I'll drop a photo later on.

[UrS4boy]

...On another note.... My fuel pump runs when I switch on the ignition, but doesn't just prime, it keeps running. I know that's not normal, but could it be the upgraded chips in my ecu causing this?

Not normal and probably nothing to do with the chips. Depends how you wired things. If the fuel pump is "running" then it should be priming, i.e. pressurizing the fuel rail.

The intermittent ECU thing could be a flakey ECU ground or, if you are using the thermal fuse on the ECU power, a flakey thermal fuse (Change it out for a spade fuse).

[edge_devil]

Thanks, looks like I need to go through it all...ps car running okay ATM so waiting for it to go wrong..

On another note.... My fuel pump runs when I switch on the ignition, but doesn't just prime, it keeps running. I know that's not normal, but could it be the upgraded chips in my ecu causing this?

[UrS4boy]

Potential solutions to why your AAN/ABY/ADU isn't starting

.. After this long preamble, the question I have is, what could cause this issue? The normal ground and 12v and lose connections on the ECU I have tried, but are there any external components (knock sensor etc) that could cause this issue? /url]

You can start by reviewing the AAN ECU pin-out documented here:

http://forums.quattroworld.com/s4s6/msgs/21009.phtml (knock sensors are not your issue)

And then move on to this:

Potential solutions to why your AAN/ABY/ADU isn't starting:

http://forums.quattroworld.com/s4s6/msgs/210191.phtml

Good luck

[edge_devil]

Hi all,

I have searched and cannot find a similar thread, forgive me if I've missed one.

First off, this is an ABY engine with the type A ecu (no immob) and it's built into a kit car. The AC and P/S pumps are removed, the original wiring loom is in use but has been shortened (by me) and the ECU is chipped, not by me.

I have added a black box with an LED and switch connected to the engine light output from the ECU so I can simply check for errors using flashing lights.

With engine running I have run the ecu test using the led, and the system returns 4444, all okay.....but last week and a few other times the engine cuts out and won't start. This could be while idling or driving. What is apparent is when I turn on the ignition, before it start the engine when the ecu is playing up the LED flickers or doesn't light up at all. When things are working fine the LED comes on and shines a solid colour as it should.

After this long preamble, the question I have is, what could cause this issue? The normal ground and 12v and lose connections on the ECU I have tried, but are there any external components (knock sensor etc) that could cause this issue?

I used this site for most of my information: http://www.sjmautotechnik.com/troubl...ng/ecu20v.html