UKPOC forums

Hi all,

Made a post a few months ago regarding my:
1997 2.5L Mazda mx6 2.5i automatic 4 speed (reg P552 AJT)

I still can’t for the life of me figure out what’s wrong with it.

I have replaced the distributor 3 times had it checked and they appear all to be functional.

Cps was replaced once and this made no difference (however I have since found out that my model was in the last 6 months of production so there is a small chance I have the wrong cps)

The timing belt looks like it spins correctly from peaking through the cover but haven’t had it properly off to check incase it’s slightly slack, but it doesn’t appear to jump teeth or look loose?

Had an auto electrician come and check the car, he couldn’t understand why it wasn’t working he said it was the distributor but this couldn’t be the case as I have had all of them benchmark checked at ignition car parts and they all work.

The code I can grab from the OBD-1 diagnostics is 04 (NE1 code or 2 I don’t remember) but either way it’s a crankshaft code

The car cranks really well, had compression tests etc in the last 12 months and the engine itself is in good shape…

Tachometer is absolutely dead when cranking so I’ve assumed this whole time the culprit relates to CPS.

If anyone has anything they recommend checking next or if they know anyone who would be willing to have it in a garage to be worked on (not many places near me are willing) I would be eternally grateful.

If not I might be getting to the end of my patience with it!
Cheers

Also another note, electrician came and sorted out the grounding point under the intake as it was a bit duff, are there any other grounding points I need to be worried about for no spark?

Apologies for the questions.
Does it crank over?
Are you getting a spark at the plugs?
Did you use the correct dizzy when changing it?
Is the firing order correct?
You replaced the CPS, but did you check the plug on the wiring side of the loom, if you have some high resistance it will not work.
These engines rely on the CPS functioning to start, once it's running it couldn't care less.

not sure where you got your CPS plug from, but RockAuto do a few.

https://www.rockauto.com/en/catalog/maz ... ensor,7196?

Hi micron,

Yes it does crank, has no problem doing that.
No there is specifically NO SPARK in any form.
All three distributors are indeed the correct ones this is not the issue.
I can check for high resistance, but to what contact points? Both the points in the loom side of connector or one of the connectors to the battery terminals???
I didn’t personally replace the CPS mechanic replaced it initially months ago

I’ll have a look at that link

High resistance on the loom side I’m guessing would just tell me there’s a dodgy wire?

Rycooda wrote: ↑

Thu Aug 27, 2026 4:09 pm

Hi micron,

Yes it does crank, has no problem doing that.
No there is specifically NO SPARK in any form.
All three distributors are indeed the correct ones this is not the issue.
I can check for high resistance, but to what contact points? Both the points in the loom side of connector or one of the connectors to the battery terminals???
I didn’t personally replace the CPS mechanic replaced it initially months ago

I’ll have a look at that link

High resistance on the loom side I’m guessing would just tell me there’s a dodgy wire?

I don't believe that it's directly the dizzy, but something that feeds in to it, maybe have a check of the wiring for the dizzy, as one of them might be broken
Who supplied the replacement CPS, does it look new?
Have you pulled the grey CPS plug apart, give it a bit of a clean and reconnect it.
If you have high resistance in the plug, then the pulse from the CPS is never going to get through. I only say the loom side, because the CPS is new?

Do you get fuel?

I don't believe that it's the immobiliser, because it wouldn't crank, but there's always a first

I think that I might have said before, but I used to own that car.

I can look at some manuals, but not until after the weekend, sorry

I don’t think it’s the dizzy wiring just because supposedly all of it read fine on voltages and as I say the tachometer doesn’t move, which is usually cohesive with a dead CPS but it’s not impossible

Been asking my mechanic where he got the CPS but he hasn’t yet responded… might just have to get a new one and try it

I have cleaned it a few times yes

I’ll try the resistance just incase it’s a fair point

I remember that on the sensor side I get 0.69 v on the pins but it doesn’t fluctuate when it’s cranking (like the spark doesn’t get past the crank teeth onto the cps)

Where as if i tap metal against it the voltage goes from 0.69 to 0.75 so it could mean the gap is bad?

Resistance on sensor side is 500 something which is normal so I’ll check loom side

If you happen to be able to look up some stuff I’d be grateful! I do remember Paul saying that this was your car initially! It’s been kept in good nick!