Rough start up and light flicker of ignition light on dash

For all electrical questions; Alternators including fitment; Light connections/wiring; Instruments; Gauges; MFA; Heater blower (not coolant related) issues etc etc.

Moderator:Scirocco Register

Forum rules
Hints, tips and guides for repair and modification - the FAQ section on the main website is worth checking first for information relating to common faults and technical help. Useful posts and guides will be added to the FAQ http://www.sciroccoregister.co.uk/scirocco-faq
Brenjacques
Posts:109
Joined:Sat Jan 19, 2019 3:07 pm
fill in the right answer:15
Re: Rough start up and light flicker of ignition light on dash

Post by Brenjacques » Sat Nov 14, 2020 6:43 pm

Well after a lot of testing I can't find anything actually wrong with it so I'll agree with you that it is just an oddity. I think if anything some dirty contacts or high resistance on the second half of the exciter wire could cause this but I'm not too bothered if there is actually nothing wrong.

I'll try and whip the plugs out tomorrow and take some photos, what do you have in mind as to the cause of the starting issue?



User avatar
james butler
Posts:2895
Joined:Fri Apr 24, 2009 1:54 pm
fill in the right answer:10
Location:birmingham

Re: Rough start up and light flicker of ignition light on dash

Post by james butler » Sun Nov 15, 2020 5:55 pm

i really need to see the plugs first before i can really say but it sounds very VERY similar to when my headgasket was going and would dribble th esmallest amount of coolant into a coupke of cylinders so when starting would sound like it was running on 2/3 cylinders, it would quickly clear and drive normally


I dont mind project cars but I HATE SANDING!!!

Brenjacques
Posts:109
Joined:Sat Jan 19, 2019 3:07 pm
fill in the right answer:15

Re: Rough start up and light flicker of ignition light on dash

Post by Brenjacques » Mon Nov 16, 2020 3:46 pm

Sounds like it could be something along those lines, I wonder if some oil is seeping through the valve stem seals, there is a bit of smoke on start up but I initially put it down to the colder days as I've only noticed it since then. I haven't topped the coolant up in a long time (way over 6 months) and it is still at the same level as I last topped it up. The only thing I top up very occasionally is the oil but there is a leak on the sump, maybe one or two valve stems aren't too good either.


I'll get the plugs out this week and take some photos if I can find where my 21mm socket has gone :-D



Brenjacques
Posts:109
Joined:Sat Jan 19, 2019 3:07 pm
fill in the right answer:15

Re: Rough start up and light flicker of ignition light on dash

Post by Brenjacques » Tue Nov 17, 2020 2:46 pm

I've uploaded some photos of each spark plug here https://www.flickr.com/photos/165005061@N07/

To me they look okay but a bit carbon fouled, I think the ignition timing needs advancing somewhat but there's no oil fouling or signs of burning coolant on them.



Brenjacques
Posts:109
Joined:Sat Jan 19, 2019 3:07 pm
fill in the right answer:15

Re: Rough start up and light flicker of ignition light on dash

Post by Brenjacques » Mon Nov 23, 2020 11:21 am

Just wondered if anyone could give some advice regarding the ignition timing. Had a look at it yesterday and the Haynes manual states the with the engine set to TDC the notch on the distributor body should line up with the rotor arm. I marked where the current settings were before I adjusted it to this but when I did the engine wouldn't fire and just spluttered slightly before dying.

There is another marking on the flywheel at some angle before TDC (must be a replacement flywheel because there are no markings as shown on other threads online but there are casting marks). I set it to this, which is also closer to my initial notch marking (when I turned the engine to TDC after) and it fired up okay but seems to be off even more than it was prior.

I'm going to look more later on, can anyone confirm that the notch on the distributor body should be in line with the rotor when the engine is at TDC. I'll probably go from the cam pulley next time if there is a marking there as I can't be certain with this replacement flywheel.

Maybe it's possible that it's running rich to compensate for bad ignition timing and it wouldn't fire last time because of overfueling.



User avatar
C 20 CCO
Posts:242
Joined:Sat Jan 06, 2018 8:38 pm
fill in the right answer:15
Location:Burnley, Lancashire.

Re: Rough start up and light flicker of ignition light on dash

Post by C 20 CCO » Mon Nov 30, 2020 11:26 am

Buy yourself a strobe light, I got one a few years ago. It proved very handy when replacing the cam belt. So much easier and because the ignition system is basic, you’ll be able to set the timing.

Going back to your ignition module from earlier in the thread, make sure there is plenty of copper grease sandwiched between the module and heat sink plate. Little or no grease means it can fry itself eventually.

Hope this helps


Sent from my iPhone using Tapatalk


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.

Brenjacques
Posts:109
Joined:Sat Jan 19, 2019 3:07 pm
fill in the right answer:15

Re: Rough start up and light flicker of ignition light on dash

Post by Brenjacques » Fri Jan 15, 2021 2:53 pm

Just thought I'd update on this thread. I sorted the ignition timing with a strobe light to the flywheel mark, it was a bit out and certainly improved things. I also had the carb tuned up properly and that is all okay now.

Still facing problems with the rough starting, almost sounds like it's misfiring when starting cold and the engine is a little shakey, runs like this for about 10-15 seconds then smooths out as the revs rise more and is fine after. I've recently fitted a new ignition coil, HT leads and plugs but this has made no improvement.

Just wondering what else to look at as prior to this it used to start fine, straight up to 2k rpm on full choke with no lumpiness.

Regarding the ignition module I did order a new one but it didn't work straight out the box so I just refitted the original. The heatsink compound was really dried out on it so I cleaned and put new compound on when refitting. I'm just wondering whether this fault could be to do with the module, although I'd expect it to either work or not.