Jump to content

Ford Zetec St170 not starting - trigger 2?


Recommended Posts


I am having trouble getting my Zetec (ST170 - zetec engine but with VVT on inlet cam) to start.

There seems to be no signal on trigger 2, which I believe is the problem. I am trying to identify if this is a wiring issue, a sensor problem or something else.

MAP, log and trigger log attached. Can anybody please give some advice? New to programmable ECU's so hoping its something obvious :-D



TriggerScopeLog 120123.llgx PC Datalog - 2023-01-4 1_01_03 pm.llgx original map JR TEST 2.pclx

Link to comment
Share on other sites

Ok, so first just a quick bit of info about the trigger scope in this ecu so you know what to expect.  Your Monsoon is an early one that didnt have the full analog triggerscope hardware (V2.4), so the parameters "Trigger Scope 1/2" which would usually show the raw voltage on the trigger pin in later ecu's arent connected to anything in your ecu so we need to ignore these. 

What we have to work with are the parameters "Trig1/2 Signal" - these are a representation of the signal that is reaching the main micro controller after they have been passed through the trigger conditioning circuit.  So if you dont see a "Trig2 Signal", it doesnt necessarily mean there is no signal - it could  mean the signal just didnt make it through the conditioning circuit.  For example if the trigger 2 voltage didnt meet the trig 2 arming threshold then the conditioning circuit wouldnt allow it through so you would see no "trig 2 signal" in your scope capture.

Many ford cam sensors output very low voltage when cranking so that would be my first thought, try dropping your trig 2 arming threshold to match the example below and see if we get a signal then.    

The second problem I see is your trigger 1 appears to be incorrect polarity as there is a falling edge right in the middle of the "missing tooth" gap.  So swap the +/- wires at the crank sensor plug.  




Link to comment
Share on other sites

Thanks for the quick response Adam.

I updated the arming threshold table as you recommended and it is now saying it has a signal.

I couldn't swap the wires at the crank sensor plug just yet as I didn't have a pin removal tool (the dealer supplied the ECU and loom but isn't being very helpful). Pin removal tool on order

I gave it a quick try to see if it would fire at all but still nothing, so I recorded a new log. Not sure if it is down to the crank sensor wiring though?

PC Datalog - 2023-01-22 3;20;47 pm.llgx

Link to comment
Share on other sites

Can you do another trigger scope while cranking.  The ecu is not commanding any dwell so that suggests it is still not happy with something about the trigger but Im not convinced it is the crank sensor or only the crank sensor.   

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...