Hi all,
Newbie member here getting to know my 1994 2.5L Probe. It's a lovely example, not perfect, but a great spec that I bought in October last year. I've done a lot to the car already (it had sat for 12 years before the previous owner bought it) but I'm having ignition issues which I'd love to know if anybody is able to help with (I'm stumped and the "code reader" I built (blinky LED) doesn't think anything's wrong).
The engine cranks, I have fuel pressure to the rail and I'm pretty sure my injectors are ok (the exhaust reeks of unburned petrol after turning the engine over). I've put a spark tester in line with my plugs and it lights, however I'm wondering if it's not quite getting the voltage it needs to create a spark... That said, there are no misfires so no evidence of a spark anywhere in the cylinder despite the tester glowing (dimply).
Could this be a coil pack issue? Or dizzy? If not, could it be the crankshaft position sensor or some sort of whacky immobiliser setup? Any advice on what it could be (and where to get decent replacement parts) would be much appreciated!
Looking forward to seeing some of you at the NEC resto show,
Ben
V6 Ignition Issues
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Bengineer_92
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Bengineer_92
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Re: V6 Ignition Issues
Amazing thank you, I'll have a poke around in the daylight and see what's what 
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Micron
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Re: V6 Ignition Issues
Hi Ben,
There could be a few reasons for your non starting.
Has the immobiliser been by-passed? do you still use a fob? If it has been by-passed, then I would check the connections behind the centre console, if it hasn't been by-passed then I would look at doing it (write up in the Oracle, accessed for £10 membership).
There is a grey plug near the dip stick, which is the CPS plug, pull it apart, give it a clean and back together again.
You dizzy could be faulty (likely if your moby hasn't been by-passed) you can have it tested, there is a company in Basildon Essex called ignition Car Parts, who repair and sell dizzy's
these are normally a good starting point.
Thanks
Trev
There could be a few reasons for your non starting.
Has the immobiliser been by-passed? do you still use a fob? If it has been by-passed, then I would check the connections behind the centre console, if it hasn't been by-passed then I would look at doing it (write up in the Oracle, accessed for £10 membership).
There is a grey plug near the dip stick, which is the CPS plug, pull it apart, give it a clean and back together again.
You dizzy could be faulty (likely if your moby hasn't been by-passed) you can have it tested, there is a company in Basildon Essex called ignition Car Parts, who repair and sell dizzy's
these are normally a good starting point.
Thanks
Trev
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Re: V6 Ignition Issues
Do NOT , EVER , leave a plug lead disconnected......it will kill the transistors in the distributor
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Bengineer_92
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Re: V6 Ignition Issues
Thanks Trev, that's really helpful.Micron wrote: ↑Wed Feb 18, 2026 9:46 amHi Ben,
There could be a few reasons for your non starting.
Has the immobiliser been by-passed? do you still use a fob? If it has been by-passed, then I would check the connections behind the centre console, if it hasn't been by-passed then I would look at doing it (write up in the Oracle, accessed for £10 membership).
There is a grey plug near the dip stick, which is the CPS plug, pull it apart, give it a clean and back together again.
You dizzy could be faulty (likely if your moby hasn't been by-passed) you can have it tested, there is a company in Basildon Essex called ignition Car Parts, who repair and sell dizzy's
these are normally a good starting point.
Thanks
Trev
I'm not using a fob but I've had the car starting pretty reliably in the weeks after I bought it so I'm confident it's not an immobiliser issue. While the engine is cranking you get a strong smell of unburned fuel from the exhaust so injectors seem to be working... I'm just not getting a spark.
There's some voltage getting to the plugs (I've had an inline tester on them) and my gaps are correct, but I suspect the voltage at the plugs just isn't enough to create an arc. This is why I'm drawn to the distributor... I've bought a replacement cap and rotor to try first, but if that doesn't work, I'll give the guys in Basildon a ring in case the transistors in the dizzy have given up (though I'm not sure how this could have happened since I bought the car).
I've noticed the issue has been worse since it's been wet which is making me wonder if the internals of the cap are wet and/or corroded... hopefully I can have a look at the weekend!
Thanks again,
Ben
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Bengineer_92
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Re: V6 Ignition Issues
Thanks for the info! I won't have done this at any point but it's good to know the danger
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Micron
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Re: V6 Ignition Issues
These dizzy’s can start to break down at anytime.
Have you checked the CPS plug?
As regards to the moby, just because it was working ok when you first got the car, doesn’t mean it’s still ok, I would check the connections of the by-pass.
The fuel will be because it’s not firing.
Have you checked the CPS plug?
As regards to the moby, just because it was working ok when you first got the car, doesn’t mean it’s still ok, I would check the connections of the by-pass.
The fuel will be because it’s not firing.
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Sunfly
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Re: V6 Ignition Issues
If it was recently starting poorly and running rough I'd suspect the Dizzy, but if it was running very nicely when you shut the engine off, I'd suspect the CPS. An engine running well in every other respect will never start with a CPS fault simply because it doesn't know the angle of the crank. The engine can continue running when a CPS goes rogue, mid journey, because the TDC sensor in the Dizzy tells the ECU where the crank is but it will NOT START without crank angle info from the CPS.
Follow Microns advice over the connector by the engine first, then check the CPS wiring hasn't fouled on the pulley, then change the CPS.
Good luck
Follow Microns advice over the connector by the engine first, then check the CPS wiring hasn't fouled on the pulley, then change the CPS.
Good luck
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Bengineer_92
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Re: V6 Ignition Issues
Thanks Sunfly that's really helpful. A replacement CPS seems straightforward enough to get hold of so I might replace it just to rule it if nothing else! I'm excited to see who's prediction's going to win...Sunfly wrote: ↑Tue Feb 24, 2026 2:06 pmIf it was recently starting poorly and running rough I'd suspect the Dizzy, but if it was running very nicely when you shut the engine off, I'd suspect the CPS. An engine running well in every other respect will never start with a CPS fault simply because it doesn't know the angle of the crank. The engine can continue running when a CPS goes rogue, mid journey, because the TDC sensor in the Dizzy tells the ECU where the crank is but it will NOT START without crank angle info from the CPS.
Follow Microns advice over the connector by the engine first, then check the CPS wiring hasn't fouled on the pulley, then change the CPS.
Good luck
All the best, Ben
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