2.9 engine ignition timing for octane rating

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2.9 engine ignition timing for octane rating

Post by simmit » Wed Apr 05, 2017 9:52 pm

Somewhere or other I have read that when lower octane/ lead free petrol was first introduced Ford recommended retarding ignition timing by a couple of degrees to suit and that was achieved in the 2.9 fuel injected engines by selecting different cable connections in the loom. Am I correct? If so, will someone advise me where the connections are located and how they ought be arranged for the now available 97 RON fuels.

My engine may be set correctly but I'd like to check for sure.



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Re: 2.9 engine ignition timing for octane rating

Post by peter freeman » Wed Apr 05, 2017 10:05 pm

There is a octane service socket next to the coil with red, blue and yellow wires - this must be disconnected from the ECU to put the system into a code 60 state. In this state the timing is fixed ( not affected by rpm ) and should be set up to 12deg BTDC - the engine should also tick over at around 850. Not my advice obviously but that of a Ford expert.



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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Wed Apr 05, 2017 10:12 pm

I thought there was an "octane plug" that you simply pulled out and plugged back in the opposite way round?


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Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Wed Apr 05, 2017 10:25 pm

From various google searches:

Octane Adjust

Pins 23 and 28 of the PCM (A147) measure the voltage drop across the octane adjust plug (D2) and uses this information to modify ignition spark advance.

--------

The EEC IV also provides a diagnostic output to a Diagnostic Plug and a simple jumper plug method for electronically adjusting the engine timing based on the fuel octane rating.Commonly called the Octane Plug

--------

the 2.9 is 12BTDC but i understand that is for 97 octain fuel and normal unleaded is 9, changing this involves disconnecting the SPOUT wire
Last edited by scimjim on Tue Apr 11, 2017 9:41 am, edited 2 times in total.


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: 2.9 engine ignition timing for octane rating

Post by simmit » Fri Apr 07, 2017 9:19 am

Thank you gentlemen.
So it seems there is an "Octane plug". My question therefore is how must it (the plug/wiring) be set to suit 97 RON fuel? For the moment I shall assume the basic timing is set correctly (at 12 deg. BTC).

I'm a simple lad and strictly clockwork so terms like "code 60", "SPOUT" and similar mean absolutely nothing to me. Simply needed to know where the plug is (thanks for "next to the coil") and how it ought be set/arranged for 97 RON. Please, keep it simple because I'm a numpty bear of very little brain.



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Re: 2.9 engine ignition timing for octane rating

Post by AJL Electronics » Fri Apr 07, 2017 11:01 am

Why bother? I don't believe that you will have any issues. Mine will not be changed from standard because I have not needed to in any 2.9i car I have driven so far. If it does pink out on the road, THEN do it. I can find the info you need when I have a bit more time.


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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Fri Apr 07, 2017 12:27 pm

Old fashioned?

Put a strobe on it and check :-)


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Fri Apr 07, 2017 12:30 pm

IIRC mine was near the coil on my GTC but that may not relate to a Middlebridge - Dave Mac wasn't known for his pretty wiring looms :-)

Image


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: 2.9 engine ignition timing for octane rating

Post by efi_sprintgte » Fri Apr 07, 2017 12:42 pm

To be honest I have found the 2.9 can take a little more advance without pinking on 95RON. The XR4x4 I had weighed a lot more then a scimitar and towed heavy trailers too with no dramas


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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Fri Apr 07, 2017 1:33 pm

AJL Electronics wrote:Why bother? I don't believe that you will have any issues. Mine will not be changed from standard because I have not needed to in any 2.9i car I have driven so far. If it does pink out on the road, THEN do it. I can find the info you need when I have a bit more time.
How do you know it's the right way round to start with?


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: 2.9 engine ignition timing for octane rating

Post by AJL Electronics » Sat Apr 08, 2017 9:32 am

Not sure why the timing adjustment isn't listed here. I was sure that I had seen it.



EEC-IV Wiring Information

Pin No Wire Colour Purpose Voltage
1 Not Used
2 Not used
3 Not Used
4 Not Used
5 Not Used
6 Not Used
7 Engine Coolant Temp 20*C-3.1V, 40*C-2.2V, 100*C-0.5V
8 Not Used
9 Not Used
10 Airconditioning Clutch On 0V Aircon Off, 12V Aircon On
11 Not Used
12 Not Used
13 Not Used
14 Not Used
15 Not Used
16 Ground 0V
17 Self Test Output (STO) PWM signal 0V-12V
18 Not Used
19 Not Used
20 Case Ground 0V
21 Idle Speed Control +8V to +11V Engine Running
22 Fuel Pump Control +12V Ignition On
23 Knock Sensor (Unleaded Only) +3V Engine Running
24 Not Used
25 Intake Air Temperature Sensor 0*C 3.9V, 20*C 3,1V, 40*C 2.2V
26 Sensor Reference Voltage +5V
27 Air Flow Sensor (Unleaded Only) Variable Voltage
28 Not Used
29 Not Used
30 Transmission Position Neutral 0V-0.1V, In gear 5Volts
31 Canister Purge 8V-10V with Engine Running
32 Not Used
33 EGR Solenoid (Unleaded) Voltage Pulse @ 1800 RPM
34 Data Output Link PWM Data
35 Canister Purge Solenoid (Unleaded) Voltage Pulse when Engine Running
35 EGR Vent Solenoid (leaded) Voltage Pulse when Engine Running @ 1800RPM
36 SPOUT (Spark Output) Ignition 7V average with Engine Running
37 Ignition Power 12V with Ignition On
38 Not Used
39 Not Used
40 Ground 0Volts
41 Not Used
42 Not Used
43 Air Flow Sensor (Leaded Only) Variable Voltage
44 Not Used
45 Not Used
46 Signal Ground 0Volts
47 Throttle Position Sensor 0.7V closed, 4.5V WOT (Wide Open)
48 Self Test Input 0Volts for Self Test, 12V Normal operation
49 Not Used
50 Not Used
51 Not Used
52 EGR Vent Solenoid (Unleaded) Voltage Pulse @ 1800 RPM
53 Not Used
54 EGR Vent Solenoid (leaded) Voltage Pulse @ 1800 RPM
55 Not Used
56 PIP Profile Ignition Pick Up 0V - 12V on Ignition PIP
57 Ignition Power 0Volts Off, 12V Ignition On
58 Fuel Injection Ignition Bank 1,3,5 PWM On Fuel Injection
59 Fuel Injection Ignition Bank 2,4,6 0Volts Off, 12V On
60 Ground 0Volts


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Re: 2.9 engine ignition timing for octane rating

Post by simmit » Tue Apr 11, 2017 9:23 am

scimjim wrote:
AJL Electronics wrote:Why bother? I don't believe that you will have any issues. Mine will not be changed from standard because I have not needed to in any 2.9i car I have driven so far. If it does pink out on the road, THEN do it. I can find the info you need when I have a bit more time.
How do you know it's the right way round to start with?
And that's the point! Thanks everyone for contributions but really all I now need to know is whether or not my "octane plug" is set suitable for RON 97, ie. which wires to which?



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Re: 2.9 engine ignition timing for octane rating

Post by scimjim » Tue Apr 11, 2017 9:40 am

scimjim wrote:Put a strobe on it and check :-)


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: 2.9 engine ignition timing for octane rating

Post by simmit » Thu Apr 13, 2017 4:41 pm

peter freeman wrote:There is a octane service socket next to the coil with red, blue and yellow wires - this must be disconnected from the ECU to put the system into a code 60 state. In this state the timing is fixed ( not affected by rpm ) and should be set up to 12deg BTDC - the engine should also tick over at around 850. Not my advice obviously but that of a Ford expert.
Thanks Peter.
I do find a connector from the loom which is about diameter and length of my little finger and has 3 wires going in (Brown, blue/brown stripe and blue/yellow stripe). This connector/plug has 3 wires out (Red, yellow and blue) which all seem commonly connected to earth at the coil mounting bracket. Is this the Octane Plug?
If it is then how must the wiring be set for 97 Ron fuel?



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Re: 2.9 engine ignition timing for octane rating

Post by peter freeman » Thu Apr 13, 2017 5:30 pm

If you send me your email address I will forward on to you the emission set up document - its 2megs so too big to send otherwise. The wiring mods are there to retard the ignition for poorer than 97 Ron fuel so I think the engine is designed for 97 anyway and the timing will not need to be touched - it seems to run ok on 95 as well not that I have done it very often - only when 97 is not available in such as Morrisons and they have given me a 10p per litre off coupon.



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