2000cc 71 Firenza not idling

[CanadianFirenza]

Hey Folks!

I have a 1971 Vauxhall Firenza SL 2000 4Speed manual Canadian Market car that I regularly drive. This car uses a single Stromberg 175 right now on of course a 2.0l slant 4.

It has gone through rounds of maintenance (points, ignition, oils, belts, air filter, new battery, running modern 91 Octane Shell V-Power Nitro+ only (for 0% ethanol), etc,.) and was running extremely well for a while.

The other day I had the car out and about and had to come to a stop on a steep hill with a stop sign on top. Once traffic cleared I got the revs up came off the clutch and the car moved into the middle of the street and calmly shut off with no stutters or sputters just gradual rev decline all the way to 0rpm. I rolled it out of the way, shut off any electronics and after letting it sit for about 5 mins it started right back up and ran well all the way home.

Ever since, the car dies at idle and refuses to idle, often without hearing any sort of choke at startup. If I keep my foot on the accelerator pedal even a touch the car runs normally, well, and smooth, but if I let it go down to idle; it shuts off again. On my last try after replacing a cracked vacuum hose I noted the car was popping quite a bit from the exhaust on deceleration as well which is new.

I am 27 and not deeply familiar with Strombergs, especially in this configuration. I have found some videos on the topic of tuning a Stromberg and have considered the condenser as well but figured I would ask here as I am not seeing a directly related past thread. I know someone (me lol) had unscrewed the damper cap and pulled out the damper to see if the carb was wet and put it back in shortly before this drive which I am considering may have been a potential source of the issue?

Pictures attached purely for reference (it is dirty with oil coating and 50+ years of use, but mechanically sound)

Stromberg 175 on 2000cc Vauxhall slant 4 Canada

Engine Bay Vauxhall Firenza 2000cc slant 4 Canada

Any suggestions, experience, or guidance would be appreciated!

[jpsmit]

first of all, 27 may make you the youngest Firenza owner on the planet.

Secondly it seems unikely that just a steep start has messed up the carb unless it dislodged something that has now clogged something else. If the car was running well it should be OK now.

some questions.

1. have you tried running it on starter fluid or even a separate fuel source? If it works, you may have dislodged something in the gas tank.

2. what colour are your plugs?

3. The cap is just to add oil for the damper - it will run better with it but won't stop running without it. If you want to add a bit of oil Transmission fluid or any light oil will do.

4. check the idle at the engine. see where the idle screw is and whether it needs adjusting

5. Message me your email and I will send you a PDF of a stromberg manual.

shouldn't be hard

[gurrier]

jpsmit,
I would venture to say that many owners are approaching or have passed the phase of the year numbers being transposed.

[gurrier]

Hi CanadianFirenza,
Don't know if you have seen this but I found it very useful to give a good understanding of the Stromberg.
https://youtu.be/M7DkaRRQ2k4
or the attached guide should an ignition system fault have occurred
https://www.dropbox.com/t/A6mBsvJE9tGkCcjg

Regards,

Bill

[CanadianFirenza]

Hey thank you for the responses!

@jpsmit:
1- no, I guess I was ruling out dislodging something by how well the car runs with even a partial press of the accelerator pedal - I will try this ASAP

2- the ends are white and green we did throw some old stock ones we had in it a few years back but it may be worth pulling and checking for buildup and gaps as it has been years now - not sure where that gets it

3- ok it had a bit of light oil recently and seems to be topped up as per the technical manuals I have and the cap is reinstalled to a normal tightness

4- The idle screw was marked with chalk from a year or so ago when I adjusted it and looks like it is in the same place, may try to move it to idle a bit higher and see if that helps ASAP

5- Done!

Thank you for all of this


@gurrier:
Haha potentially! I have found some younger owners on Instagram many around my age but in different countries of course (NZ, South Africa, UK, AU etc,.)


I am going to review the video and that guide ASAP they both look quite promising

Thank you for the response!


I will respond once I have time to go through all of this information and confirm - hopefully the next you hear is the car is back up and running

[HC Fairley]

@gurrier:
Haha potentially! I have found some younger owners on Instagram many around my age but in different countries of course (NZ, South Africa, UK, AU etc,.)

There are a few of us out there. I'm 22 and have 2 Vivas at home and a third in storage to be tackled at a later date. Also had a 4th one a few years ago that was dug out of a hedge local to me, it was absolutely rotten but did have some useful parts I was able to scavenge off it before it went to the scrappers. The vivas on top of a 79 Trans Am a while ago (since gone) and a Rover 620 Ti, not to mention the daily runner Mondeo, you're in good company especially if you want to start hoarding

I know of 2 or 3 on this forum in their 20's and another few on the likes of Instagram as you have mentioned who wouldn't be as active here, the first that springs to mind is JP Lennard or Floyd.1968 on Insta, he built a Turbocharged HB Viva recently, he's maybe 24 at most.

[CanadianFirenza]

So the car is running!

This car never fails to live up to the nickname "Fairweather Firenza"

I figured I would take the carb apart a bit disconnect and reconnect the battery and let it sit for a few days and see where it was at before starting down some of these recommendations since most stuff did seem within spec. Today I went to start it, and it started on the first crank, choked well, and ended up finding it's idle again which sounds pretty healthy but maybe a touch high. Another start and run later helped solidify it is running well.

I am going through some light carb tuning and got idle down a touch but running well seemed pretty in tune. May have been the damper cap removal plus a new battery in some mystery mix, it has done this before lol.

Either way, planning to do oil and plugs again soon since after looking the plugs are pretty old, it really does love this shell fuel though.

I appreciate the help, at this stage I am not going to mess with much more as it seems to hate changes more than it loves fixes themselves



@HC Fairley nice to meet you! Yeah I have followed floyd for a bit aka @floyd.1968. Some folks I have found on social media would be @hexytech who has instagram and youtube and is doing a high quality LS swap, @bad_dr3am who has a gorgeous fastback in NZ on instagram, @lotechshed who has a few I believe on instagram, and @_stef.28 who is doing some good work on a 4door south african Firenza on instagram! and myself @thyjesster haha.

I got my first Firenza when I was about 12 (blue project car still a project car) and the silver one when I was 19 in university after following it for years and finding it go for sale when the original owner passed but only recently have my own home and garage to actually live with the car. I am glad to see people appreciate this chassis!