2 years on and losing faith...

So, due to circumstances, not really had the pennies to be able to afford a mechanic to sort out the supe, so very slowly when I've actually had a whole 5 minutes, I've done bits and bobs myself. But my mechanical skills stretch not much further than changing a wheel, plus the odd things over picked up over the years.

So, for the issue I'm having, originally it started having a hissy fit when trying to start it, sometimes it would, sometimes not at all for days. I narrowed it down myself to possibly being the igniter module. I bought another, and it did seem to make a little difference as it would now attempt to start. Since that point I have replaced everything to do with the ignition except for the barrel and key.

Two weeks ago, it finally fired up and ran on idle after a little tweaking with timing gun.

From there, when starting first time during a day, it would be a big struggle, once fired up, idling seemed to be running the opposite way around. Low start, turning to high idle.

Now, I'm back to square one, no spark from coil. I know nothing about the electrical side of the car, but I am aware the central wire going into the igniter module is constant power, can't remember which, either black/red or black/orange. Both of these wires run to the coil pack, one of these is constant still and sending power. I decided to buy another igniter module hoping this was my problem again. Nope, the car turns and such, but still no spark.

So, due to circumstances, not really had the pennies to be able to afford a mechanic to sort out the supe, so very slowly when I've actually had a whole 5 minutes, I've done bits and bobs myself. But my mechanical skills stretch not much further than changing a wheel, plus the odd things over picked up over the years.

So, for the issue I'm having, originally it started having a hissy fit when trying to start it, sometimes it would, sometimes not at all for days. I narrowed it down myself to possibly being the igniter module. I bought another, and it did seem to make a little difference as it would now attempt to start. Since that point I have replaced everything to do with the ignition except for the barrel and key.

Two weeks ago, it finally fired up and ran on idle after a little tweaking with timing gun.

From there, when starting first time during a day, it would be a big struggle, once fired up, idling seemed to be running the opposite way around. Low start, turning to high idle.

Now, I'm back to square one, no spark from coil. I know nothing about the electrical side of the car, but I am aware the central wire going into the igniter module is constant power, can't remember which, either black/red or black/orange. Both of these wires run to the coil pack, one of these is constant still and sending power. I decided to buy another igniter module hoping this was my problem again. Nope, the car turns and such, but still no spark.

I wouldn't lose faith after two years. Give it a bit longer. There has to be someone near to you who could help out. There are so many things it could be beyond electrical. It sounds like it could as easily be a fuel problem. Hopefully someone can come over, maybe run a compression test and check out the timing and spark for you and also check the fuel pump pressure and get you rolling again.

Thanks rider. Done compression test. Fuel pump still strong and feeding fuel.

Just doesn't want to spark from the main coil lead. But as I say, I've replaced every single thing beyond the ignition barrel running all the way to the spark plugs.

I say two years, but that's just the starting it up issue, a year and half before that was a gearbox problem, which I am not sure if it's resolved now because I can't drive the damn thing

Alarm/immobiliser been checked and passed as working properly?

Not yet, it's a clifford but doesn't have immobiliser pedro

We're assuming that you've begun with the basics and disconnected then reconnected the battery and not taken for granted that it's got good contacts? Sounds like your ECU could have a bad ground connection. Don't ask me where it is but it could screw everything up randomly depending upon humidity and two weeks ago it rained a lot down here in Hertfordshire so I would bet that you had more than us in Yorkshire. Also the Idle speed control valve, (if we even have them? If not, the 'modern' equivalent) and throttle/cam position sensors etc. could be issues. It would be worth checking the cam belt timing sprockets in case you've jumped a tooth but my money would be on the idle control side of things. A few years ago you'd have been inundated with help. I haven't logged on in ages but it seems very quiet around here.

Is this for an NA or TT?

Is this for an NA or TT?

As hes talking about timing guns i assume NA

So, due to circumstances, not really had the pennies to be able to afford a mechanic to sort out the supe, so very slowly when I've actually had a whole 5 minutes, I've done bits and bobs myself. But my mechanical skills stretch not much further than changing a wheel, plus the odd things over picked up over the years.

So, for the issue I'm having, originally it started having a hissy fit when trying to start it, sometimes it would, sometimes not at all for days. I narrowed it down myself to possibly being the igniter module. I bought another, and it did seem to make a little difference as it would now attempt to start. Since that point I have replaced everything to do with the ignition except for the barrel and key.

Two weeks ago, it finally fired up and ran on idle after a little tweaking with timing gun.

From there, when starting first time during a day, it would be a big struggle, once fired up, idling seemed to be running the opposite way around. Low start, turning to high idle.

Now, I'm back to square one, no spark from coil. I know nothing about the electrical side of the car, but I am aware the central wire going into the igniter module is constant power, can't remember which, either black/red or black/orange. Both of these wires run to the coil pack, one of these is constant still and sending power. I decided to buy another igniter module hoping this was my problem again. Nope, the car turns and such, but still no spark.

Buy some Easi Start and spray it into the plenum by removing the air filter element and having someone spray a good dose into the air box with the lid off while you crank it. Does it try and fire and run then? Yes? Look to fuelling issues. no? Look to no spark or weak spark issues. What would i do if you brought it here? remove all plugs and compression test. FIT NEW PLUGS or sand blast the old ones if they look almost new. Check cam timing, check fuel pressure. Attempt to start while monitoring injector on time. Use that to see if the ECU is commanding a sensible injection time. At same time monitor LT and HT spark voltages.

But you can do a LOT with a multi meter and a few basic tools if you are patient and go about it logically.

If you want to dive in with a wild card check the water temp sensor for the ECU resistance **AT THE ECU CONNECTOR PLUG**, with it unplugged from the ECU itself. On the limited info you give and if forced to make a wild stab at it, i would say you may have a water temp (ECU *NOT* temp gauge) sensor issue.

All this is dependent on you getting a good spark from the coil king lead to engine ground when cranking.

A few years ago you'd have been inundated with help. I haven't logged on in ages but it seems very quiet around here.

It is very quiet compared to a few years ago, maybe a couple of mods still happen by but that's about it. Lots of singles have died in bits and many people moved onto Datsuns. The only 'busy' section these days is parts so if the OP decides to break his car, then there will still be lots of interest.

Maybe the mk4 is just to specialist today with not many doing many miles as most now seem to be parked up for posterity, something I admit to being guilty of but after 19 years of trouble free ownership it deserves a comfortable retirement. If the OP lived close to me, I'd be available to pop over to see if I could help out so hopefully all the good spirited Yorkshire owners will be in touch to offer their support and services.

Cheers guys.

I'll look into those points Chris. I know it was a bit of a rambling on, but the main issue I guess is, theres no spark at all from the king lead. Yet I have replaced all replaceable parts, 2x igniter modules, coil pack, leads, full dizzy, plugs. Straight away with all parts replaced, with an effort, it finally came to life, not perfectly, but ran, but each time I touched the accelerator it would die.

I'm not sure if this info makes any difference but, I tested the plug to the igniter module, obviously the central wire (b/o) is constant power, and seems fine, then there's the b/r wire but can't remember what it is, both run from the module to coil, power still feels that direction too. But just out of curiosity, I tested the module for ground, no issue there. What I thought was strange is, the central pin in the modules socket that receives the power, shows a faint ground too.. I doubt it is a module problem if indeed this isn't normal, as all 3 modules I've used showed the same.

Thanks rider, can't say I've ever been on a forum that's ever been any friendlier

Just incase you haven't seen this it might be of help to you

http://www.mkivsupra.net/vbb/content.php?61-Diagnostics

Cheers guys.

I'll look into those points Chris. I know it was a bit of a rambling on, but the main issue I guess is, theres no spark at all from the king lead. Yet I have replaced all replaceable parts, 2x igniter modules, coil pack, leads, full dizzy, plugs. Straight away with all parts replaced, with an effort, it finally came to life, not perfectly, but ran, but each time I touched the accelerator it would die.

I'm not sure if this info makes any difference but, I tested the plug to the igniter module, obviously the central wire (b/o) is constant power, and seems fine, then there's the b/r wire but can't remember what it is, both run from the module to coil, power still feels that direction too. But just out of curiosity, I tested the module for ground, no issue there. What I thought was strange is, the central pin in the modules socket that receives the power, shows a faint ground too.. I doubt it is a module problem if indeed this isn't normal, as all 3 modules I've used showed the same.

Thanks rider, can't say I've ever been on a forum that's ever been any friendlier

You need a scope on it, or an AJ6 tester (my AJ6 tesyer is 30 years old, but a super bit of simple kit, it emits a pulse to mimic a crank or disi, and it can receive a pulse, to see if a crank or disi sensor is working and sending out a signal). I have never tried it but a multi meter set to a low voltage AC range might show if the disi star wheel and coil is giving an output when cranked. A none LED test lamp should show if the coil itself is getting LT pulses from the ignitor module. Go to YouTube and search for no spark testing, there should be plenty of stuff there.

Ah cheers Chris

Morning all. Wanted to give you an update.

Done some testing, coil works, igniter works, checked igt signal from ecu harness, that's reading (.050-ish). Did the igt lead from igniter to coil, that works.

Yet still no spark when all put back together.

Also, I'm not sure if this helps, but I keep getting error 22 and my ignition barrel light won't go out when there's no key in it and doors are closed.q

Would anyone know if I where looking at needing a new ecu? Or possibly ignition switch?

Also, error 22 has been replaced by 12

http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13920&d=1112558346

Error 12 could be crank / cam sensor?

I got this error when my timing star fell off the crank and hit the crank sensor breaking it.

Ouch that's not good. I'm wondering if then it's due to having complete dizzy replacement. Probably not set correctly.

I wiped the codes yesterday and now found 3:

12, 13 and 22

It's the Ecu! Just had the same problem, open it up, look at the capacitors, they leak over the board and that's it, bang goes the Ecu! They are fixable sometimes, but worth a check as it takes 15 mins, located under for he passenger footwell

I literally replaced everything before checking the Ecu, plugged a mates Ecu in and boom, ran like a dream. You can use a manual Ecu to see if it starts but you won't be able to drive it, make sure you get the right Ecu for your car, a soarer one won't fit, supra ones have completely different plugs, you'll need this one

You can text me on 07428969066 and I'll be more than happy to talk you through it, I'm not on here often really!

Surely there must be a member not far from you with an NA that you could swap the ECU with

and see if your problem is cured.

Pop up a post in supra chat as that gets the most traffic on here

Cheers everyone. Just finished work. Will be over at garage later and will pop ecu out and have a look