Starting/Misfiring/Stalling problem

[dogan]

Okay so I have had an intermittent issue for the past couple of months where my 4age conversion in my KE70 would become hard to start, misfire and stall.

At that point I had noticed that the ground wire to the igniter on the coil pack had come loose and torn off, i just patched it back up and it was good for another week or two until the same thing happened, again it seemed to be the earth wire as it had come loose again because of the quick patch i had done last time.
Only difference is that this time whether the ground was good or not it still wouldn't start or would start, misfire and bog down the moment any kind of throttle was given. So looked around and found that a terminal came loose off of one of my relays. Fixed that up and was good for another week and now im having the exact same problem but this time the ground to the Igniter is good and solid, all terminals on all the relays are good and i also have spark going to the plugs. I assumed it might have been a fuel pump issue but upon pulling the fuel hose off the fuel filter and cranking i can see that there is definitely fuel going to the rail..

Any help or ideas of what to check will be appreciated!!

[Slimer86]

Check all earth connection. Also where earths were previously loose and causing issues, clean up the connection with wire brush/emery cloth and contact cleaner, as it is likely that it was arcing at that point and causing reoccurring issues.

[dogan]

I have been over the earths over and over again and I still haven't got it running. It's actually worse now than before.

While going over my wiring, i noticed some exposed wires where the distributors plugs were so i re-did the plug. Also i noticed that the wires inside the distributor were rock hard and the insulation was cracked. Eventually i sourced another dizzy to try.

Once the other distributor was in, it fired up right away perfectly! Idled well, revved well, didnt misfire. Tried it again the next day to have the same issue as before! Started with a roughish idle and just really not right, I thought id check and adjust the timing but once i moved the dizzy plug the car shut off and after that it has been GAME OVER!

Now the fuel pump doesn't even pump while I'm cranking. I have checked the COR relay and there is definitely power coming to it and power going to the Fuel pump through the COR relay.

After this i checked all the other relays and made sure there weren't any loose connectors etc. All good.



Does the fuel pump work off the distributor some how??

Is there a way to test my distributors??

Would the igniter have anything to do with this?? How can i test that??



ANY HELP WILL BE GREATLY APPRECIATED!

[LittleRedSpirit]

Did you pop the cover off the ecu and check the condition of the capacitors? Some people have had random or intermittent performance from the circuits showing their age. It seems you took the dizzy itself out of the equation by experiencing the same issues with both units. Might be a wiring or ecu issue. AFAIK the ecu triggers the COR for the fuel pump. Not the dizy.

[Matt]

The first thing I'd be checking is the condition of the dizzy plug on the engine harness, as it is very common for these to break and given the last thing that was touched was the dizzy plug before the car shut off it is a good starting point.

I also suspect the Circuit open relay isn't wired correctly with the starter signal (12v whilst cranking) to the relay. Usually this doesn't cause a problem, as the ecu detects the engine is turning over and provides the ground to the relay. Plus the fuel rail usually remains pressured and there is enough fuel to start the car. If you've always found the car takes a bit to start this would be why.

The dizzy itself doesn't control the fuel pump, but the signals from it are used by the ecu to detect a running condition. On an ae82, you can rotate the dizzy and the fuel pump in most instances will run.

IF you have power going to the fuel pump and it isn't running the rail is empty, check the earth at the pump but it is likely your fuel pump is shot. Measure the resistance of the pump to be sure.

Hope this helps

[dogan]

Thanks for all the help! Turned out to be a partially cut cable to the fuel pump, and also the distributors plug on the loom side which I had redone before wasn't seating inside the plug.