Ignition Timing question

[ketvrin]

I did search but found no specific answer on this topic, so suggestions please...

I refitted my dissy and set the timing according to the Sierra manual - rotor pointing to #1 and mark on pulley lined up with 12 degrees. The engine fires and runs OK but is a bit hesitant on acceleration and pops and bangs more than usual on over-run.

Now I remember reading somewhere that I need to change the timing if using 97/98 U/L but what to ? and can the timing be adjusted by turning the dissy or do I need to earth an ECU connection to achieve the change in timing (read that somewhere too ???)

I also saw Tvrgit (I think? apologies if it was not you ...)advising someone that it takes 4 or 5 hot/cold cycles before the ECU overcomes the effect of being disconnected - effects similar to throttle pot problem ?

so whats the timing setting for running on 97/98 RON and how do I reset it ?

[ijbd]

Ketvrin,

you need to attach a startester (Loewener/Mabeco) to the running engine.
I assume you have to leave this to a TVR/Ford dealer.
The tester does a selftest of the EEC, then gives out signals to adjust.
Code 60 is start adjusting, 70 is stop adjusting.

Leaded/unleaded adjustment is by means of a jumper on the multiplug of the EEC, the pins are in the bible.

mvg Boudewijn

[Jed-S]

Something like the Gunsons fault code reader will put the ECU into service mode (although the manual with mine was wrong) to allow you to adjust the timing.



Edit to say: I'd initially set my ignition to 9 BTDC without using the service mode but when in service mode it was a 0 degrees. Chances are your dizzy is out of position if you've timed in without placing it in servce mode.

Edited by Jed-S on Monday 9th July 08:09

[ketvrin]

OK I have the bible (first edition) in front of me now and it describes how to earth wires on the "octane adjustment plug" but also says that for my ECU type (88BB12A650JA) I dont need to make adjustments for 95 ULG but does not say anything about further adjustments for 97/98 ???

what does the "octane adjustment plug" look like ? I have two plugs, one with a black cover and the other with a red?



I have bought a gunsens tester and await its delivery...

K

Edited by ketvrin on Monday 9th July 08:47

[ketvrin]

Thaks for the email Jed, that explains what I need change the setting to - or maybe I should just go back to and stick to 95 RON ???

[jimed]

That can't be a proper TVR owner's hands above - they are far too clean ..
Jim

[ketvrin]

jimed said:

That can't be a proper TVR owner's hands above - they are far too clean ..
Jim

you are looking at the skin grafts I had after the winter refurb mate

[Jed-S]

The red one is the one used for retarding the ignition by the 4 or 6 degrees. The black one is the one where the fault reader/STAR unit goes.

[ketvrin]

Thanks Jed

I dont suppose you know what the other "danglers" are do you? there is a red relay and a yellow relay plus theres a purple connection which simply holds a 30amp fuse.

I dont like unidentified danglers

[baggiebird]

Been thinking about this as I was fettling my S3c yesterday. Checked timing with strobe light on Nr 1 cylinder, reads 17-18 deg. BTDC estimated at 900 rpm. Reset to 12 deg. BTDC by moving distributor - and re clamping, which Haynes manual for Sierra 2.8/2.9 appears to advocate. Then checked timing several times it is still 12 deg. BTDC and appears to advance normally as engine speed increased. Accept that full diagnostic check with Ford kit would be even better but how far out can mine be doing it this way?

[tvrgit]

ketvrin said:

I also saw Tvrgit (I think? apologies if it was not you ...)advising someone that it takes 4 or 5 hot/cold cycles before the ECU overcomes the effect of being disconnected - effects similar to throttle pot problem?

Good memory - I did say that on mine at least, if I disconnect the battery, then the car seems to settle on a "fast idle" even after it has warmed up - it will continue like that for ages (days) until you leave it to idle, it gets hot, the fan cuts in, then it's perfect again until the next time the battery is disconnected.

It's almost as if it forgets where "hot" is, so thinks the engine is always "cold" until the first time it gets properly hot, then it remembers the proper "cold" range that needs the extra fuel (forgive the technical jargon there).

It's probably symptomatic of something else to be honest, my car runs terribly when it's cold (so does my nose but we'll overlook that eh?) so I don't think the "cold start" circuits work well - it always starts and idles but won't pull smoothly till its warm.

[Barkychoc]

ketvrin said:

OK I have the bible (first edition) in front of me now and it describes how to earth wires on the "octane adjustment plug" but also says that for my ECU type (88BB12A650JA) I dont need to make adjustments for 95 ULG but does not say anything about further adjustments for 97/98 ???

what does the "octane adjustment plug" look like ? I have two plugs, one with a black cover and the other with a red?



I have bought a gunsens tester and await its delivery...

K

Bet you can't get that lot back in without swearing......

Edited by Barkychoc on Monday 9th July 16:19

[ketvrin]

I think years of backpacking, touring on motorbikes and cramming a fortnights gear into small car boots gave me packing skills that were tested to the limit... I did swear however

[Jed-S]

baggiebird said:

Been thinking about this as I was fettling my S3c yesterday. Checked timing with strobe light on Nr 1 cylinder, reads 17-18 deg. BTDC estimated at 900 rpm. Reset to 12 deg. BTDC by moving distributor - and re clamping, which Haynes manual for Sierra 2.8/2.9 appears to advocate. Then checked timing several times it is still 12 deg. BTDC and appears to advance normally as engine speed increased. Accept that full diagnostic check with Ford kit would be even better but how far out can mine be doing it this way?

The problem with not placing it in service mode when you adjust it is that the idle control valve will be compensating for the engine idle speed. It is worth getting a Gunsons FCR for the 15 or so quid that they cost on ebay.