Urgent Help Needed

[fifthorda]

Well, I thought I had fixed my problem. I didnt. I need to get this car on the road ASAP, since it will now be my dd since my other car needs serious repairs. I do not have spark. When I turn the key to on, it sparks once and thats it. When I crank it (it does turn over) theres nothing. I can smell fuel ( I dont know if its the cold start or the actual injector that are fireing.) Car is an 85, with a fresh 83 rebuilt motor. It ran when I got it ( had terrible rod knock). Things I have done
1. test the coil = good
2. try another coil = same things, sparks once when key on
2. test dizzy = good
3. check fuses = good
4. check grounds = good (removed coil and ingniter and buffed behind them)
5. check power at ecu (bat terminal, and ign. switch) = ign switch terminal has power when key on, bat never has power
6. Added 12 volt source to ecu (bat.) = no change
7. Swap ecu = no change

I am out of solutions. Where should I look next? I would need this car for the weekend if possible.

[omarty]

How are you determining it only sparks once? how are you checking to see it is or is not sparking? There are more qualified people here to help you but i think this is where they will start.

[AJ]

I would put in new fuse in the EFI,good fuses can be bad...

Change ignitor, be careful testing you can burn it out if not...

[83CelWA]

What style ignitor are you using? The one with the one large plug? Or the 2 smaller plugs? If it is the one with the one large plug, swap that plug and the one from the injector resistor and see what happens.

[fifthorda]

Im testing it with the coil lead. I will try another igniter tonight. I am using one with two connectors. My spare is with the single connector. Is this ok?

[foxhound]

Is there a crank or cam positioning sensor on our cars we can check?

[bozosoku]

There is no crank or cam position sensor other than the dizzy. Probe voltage at the ECU terminals under this link

http://www.cygnusx1.net/Supra/Library/TSRM/MK2/manual.aspx?S=FI&P=76

If there is no BAT voltage something is wrong, recheck your wiring.

[83CelWA]

Im testing it with the coil lead. I will try another igniter tonight. I am using one with two connectors. My spare is with the single connector. Is this ok?

You would have to swap the plug on the spare, for some reason Toyota decided to make things a little more difficult and around '84, they changed the ignitor plug to the single style instead of the earlier style with the two single connectors. The thing that makes this difficult is that the single plug is also the same style plug for the injector resistor and I have seen it a few times where the wrong plug was used for the wrong component.

[fifthorda]

What could be the reasons for no voltage at bat?

[83CelWA]

What do you mean? If your battery is not putting out any voltage, it is a dead battery.

[Linga]

Check the grounds that bolt to the intake manifold. When i forgot to put these on it would spark once when i turned the key on but had nothing otherwise. If you haven't taken off the intake manifold maybe one broke or you have a bad connection there. They are really hard to see but there is a cluster of ground wires that attach to a bolt for the intake.

[fifthorda]

What do you mean? If your battery is not putting out any voltage, it is a dead battery.

Loll :duh: Dont worry I'm not new to mechanical work. Ive done a few builds, and thats also what Im studying in. Im saying 0 v at bat terminal on ecu, as I stated earlier. I now have all the electrical diagrams i could get from mitchell1 (much better than the tsrm, if anyone wants them I could put them up). Ill try to find where theres a problem.

to linga: the engine was COMPLETELY rebuilt, which means taking the engine out, and removing the grounds. That ground is on tight. I have good ground at ecu.

[83CelWA]

Does this also mean you checked ALL the fuses in the engine bay and drivers side kick panel? Also check the pink fuseable link that is in the fuse box in the engine bay.

[fifthorda]

Yep they all appear to be good. If all else fails Ill try replacing them, as sometimes fuses which seem to be good, arent. The bat. terminal seems to be connected to the headlight retainer relay (from looking at the diagrams), which I bypassed. Ill see if my problem is there. But it still didnt work with 12v current to the terminal so Im not sure that would affect anything...

[StanS]

disconnect ecu and see if there's correct voltage at bat terminal.

[fifthorda]

As I said earlier, there is none. If I add direct 12v current, it still doesnt work.

[fifthorda]

Problem solved. Mistake was on my part. When I removed the wiring harness, I also removed the connectors to clean the connections inside. WHen I reassembled the ignitor connector, I swapped the green with white line for the solid green one :(:S Now I get spark out of the coil, but when I plug it into the dizzy cap, it doesnt reach the plugs. The problem will be much easier to find. Ill change the rotor. I already have a new cap.

[AJ]

Nice find!! It usually the basic stuff, when you have ruled out the electronics/sensors...


Problem solved. Mistake was on my part. When I removed the wiring harness, I also removed the connectors to clean the connections inside. WHen I reassembled the ignitor connector, I swapped the green with white line for the solid green one :(:S Now I get spark out of the coil, but when I plug it into the dizzy cap, it doesnt reach the plugs. The problem will be much easier to find. Ill change the rotor. I already have a new cap.

[StanS]

You could have had an internal short to ground in both ecu's. Checking the ecu bat terminal with the ecu disconnected would determine that the voltage is not getting to the terminal and that an internal ecu short is not the problem.

Also, in general, replacing a part doesn't mean that the new part (if untested) is good.