[Mk2] [NA] Missing plug next to fuse box amd no spark.

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Eksterminator
Posts: 52
Joined: Fri Jun 25, 2010 2:47 pm
Location: Hayes (London)

[Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by Eksterminator »

My faulty alternator burned some wires in the loom of 1991 UK Rev 1 (??) 3S-GE so I changed the whole engine wiring looms (including the passenger loom leading to it on 1993 rev2 UK and I took the 1993 ECU as well.
Now there's no ignition and I dont know why :/
I measured all ECU signals and they seemed to be fine apart of IGT signal - it should show some low voltage once the engine is idling, but I cant measure it as the engine is not starting (just cranking).
There is the 12V on ignition coil and all earths fine.
I got no idea why it doesn't start.
The alternator is disconnected (as is damaged), lambda sensor is missing as the 1991 haven't had one and there is something missing just next to the fuse box. The unplugged plug got 2 W-B and G-W wires as on the picture enclosed.
Can any of this prevent the engine from starting ?
My Jap version starts without alternator plug connected and there's also no any IGT signal when the engine is not running (ignition ON) - so I dont think that's the case. I've been told the engine was running on the wiring and ECU. I think that the engine inlet pipes was a bit thicker on the 1993 donor, but it got nothing to do with ignition - maybe a bit with mixture, but it should start I think.
The old ECU got different ignition pinouts and variable resistor circuit so I'm not wondering why it's not firing on the old one.

Is anybody know what should go to the plug ?! It's cable is factory zipped to some small plate which was bolted to the engine bulkhead - there was something on it in stock I think.
I think it was missing already when I took the stuff from the donor car.
The wires colors indicates stop light circuit, but I don't think that there's any stop light going into it.
I think the donor was manual car and the ECU says its manual, but it got some AUTOMATIC version pinouts...

http://imageshack.com/a/img921/6107/OkDSbS.jpg
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abovetherim
Posts: 594
Joined: Wed Feb 16, 2011 8:49 pm
Location: Leicester

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by abovetherim »

Have you checked all the fuses as wire shorts could have taken some out
Are you getting spark?
Are you getting Fuel?
This could help point in the right direction.

Also jap version will have idle up valve on the rear bulk head for the aircon.
Did the donor car have cold start injector so the ecu is mising signal from the cold start switch??

Will it fire up if you spray easystart in the intake?
Eksterminator
Posts: 52
Joined: Fri Jun 25, 2010 2:47 pm
Location: Hayes (London)

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by Eksterminator »

I checked any silly stuff (I'm not a noob).
There's no spark, but fuel is getting on spark plugs. I replaced everything relevant to ignition from my running Jap rev1, apart of the coils under dizzy cap.
I cant see reason why would they burn so I didn't even measured resistance.
I will check it and if it will be fine I will repin ECU connectors for original rev 1 ECU and will add variable resistor + some little wiring changes to make it work as rev 1 assuming the rev2 ecu must be damaged.
If it will not help than I will have to check all the engnine sensors and wiring...
I put 2 diferent wiring looms already and both at first wasn't cranking but once I put the key back to off position battery light was flashing a little (like there was not much voltage) I could hear (starter ?) relay clicking on and off like crazy and the engine was trying to crank but alternator shortcircuit was draining too much current.
I took the alternator off as it was causing the problems, but I don't thinkg it burned anything.

My biggest concern is about the funny plug I pictured - maybe it got anything to do with no ignition problem.
I thought it's a plug for charcoal canister but it doesnt fit. I guess it must be connected with EVAP ECU pinout, but I dont know why the plug is different and shorter cable - plug looks stock...
abovetherim
Posts: 594
Joined: Wed Feb 16, 2011 8:49 pm
Location: Leicester

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by abovetherim »

Would the cable on the mystery plug reach the speedo sensor on the gearbox as the rev1 is cable but rev2+ is electric?
You say you are not a noob so it is safe to assume that the plug isn't the one for the coil? And the coil meters out OK and the bracket for the coil and ignitor earths properly?
abovetherim
Posts: 594
Joined: Wed Feb 16, 2011 8:49 pm
Location: Leicester

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by abovetherim »

Would the cable on the mystery plug reach the speedo sensor on the gearbox as the rev1 is cable but rev2+ is electric?
You say you are not a noob so it is safe to assume that the plug isn't the one for the coil? And the coil meters out OK and the bracket for the coil and ignitor earths properly?
Eksterminator
Posts: 52
Joined: Fri Jun 25, 2010 2:47 pm
Location: Hayes (London)

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by Eksterminator »

No, the speedo plug is unplugged - the cable is very short - it's little off of the cable going to idle-up valve (the one to idle up a bit once the A/C is on).
Coil is not using it's housing as earth (unless additionally) anyway the earths are good.
Maybe some sensor is draining the ignition signal in some way.
I'm thinking if it may be drained somehow from tacho as I've changed whole back looms twice with same results... It's I think a problem in front loom or on engine, as I can't believe 2 looms and ECU's are damaged.
BTW, I checked one of them (the original one) on my Jap version - it got different part code but the same pinouts on PCB inside. It starts but cranking longer than usual. I guess that because Jap version got better air-in flow due to thicker inlets and Jap map is richer.
As far as I understand it starts 'manually' at first and all the additional engine controls like lambda etc start once the engine is running already (apart of few things like temp. relevant switches).
mr2magic
Posts: 643
Joined: Fri Apr 09, 2010 9:33 am
Location: Hannover, Germany

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by mr2magic »

My guess would be you've forgotten to plug in the connector to the distributer housing (4 pin) or the wiring to/from that connector is broken.
Eksterminator
Posts: 52
Joined: Fri Jun 25, 2010 2:47 pm
Location: Hayes (London)

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by Eksterminator »

Everything is plugged properly, but I will measure if the coils connected to it got continuity (I really don't think they're damaged - this kind of things lasts forever).
mr2magic
Posts: 643
Joined: Fri Apr 09, 2010 9:33 am
Location: Hannover, Germany

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by mr2magic »

Could it maybe be some kind of immobiliser?
Eksterminator
Posts: 52
Joined: Fri Jun 25, 2010 2:47 pm
Location: Hayes (London)

Re: [Mk2] [NA] Missing plug next to fuse box amd no spark.

Post by Eksterminator »

mr2magic wrote:Could it maybe be some kind of immobiliser?

I've been thinking if maybe Toyota added some immo in 1993 ECU, but no pinout on PCB indicates anything like that. I'm sure it's not any aftermarket immo blocking it as there is alarm in the car and I didn't know at first how to disarm it once it go on at the first time so I've found the solution to run the car within 2 min. and couldn't believe it worked...
Once the ignition was on and alarm armed I could run the car by a starter relay shortcircuit.
I don't think that any common immobilisers are relevant to back wirings. As long as there's the voltage for ignition and all ECU voltages it should fire unless the ECU is xxxxx or some ignition wiring or something is messing up ignition signals. I'm thinking if maybe the igniter is not compatibile with 1993 ECU as the spark lead and distributor leads are smaller diameter so I fited the 1991 ignition stuff from working Jap car (it was the same size as original) but still doesn't fire.


KAY QUESTION:
Do You think that different year igniter may be incompatibile with 1993 ECU ??

I haven't got 1993 distributor, but I think that distributor, trigger coil etc works the same regardless of leads connection diameter so I think that I can swap over the igniters to make it work with different coil. Do You think that it may help ?
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