Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > PV, 120 (Amazon), 1800 General

Notices

PV, 120 (Amazon), 1800 General Forum for the Volvo PV, 120 and 1800 cars

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

Misfire

Views : 1016

Replies : 16

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Aug 14th, 2018, 11:13   #11
arcturus
arcturus
 
arcturus's Avatar
 

Last Online: Today 09:21
Join Date: Mar 2006
Location: Sagres Portugal
Default

The latest. now they seem to accept that there is a problem with the unit

Hello George,

Most of the time spykes on the board net occurs when the battery is full of charge and the voltage regulator starts working.

When the misfires are constantly there, also when you just start the engine after it was off for a long time, there is maybe something else wrong.

Normally the alternator test is very easy when the 123ignition was still mounted in the engine. In your case it is already removed.

Please send the ignition to us for a check.
__________________
life's too short to drink bad wine
arcturus is offline   Reply With Quote
Old Aug 16th, 2018, 21:08   #12
Ron Kwas
Premier Member
 
Ron Kwas's Avatar
 

Last Online: Today 14:29
Join Date: Jul 2007
Location: Connecticut, USA
Default

Arcturus;

I have some news...in part from the Volvoniacs Forum ( http://www.networksvolvoniacs.org/in...7s_zuv....html ), where Juergen says his 6V car runs fine with it, and checked documentation where the unit is specified to operate from 4-15V...BUT...if you note the voltage collapse which occurs during Starting in this video https://www.youtube.com/watch?v=PzDj49BF4V0 where I can see 3.2V(!) it is clear to me that the unit is at the fringes of its operating range during Starting...maybe it works...maybe it doesn't...and that easily explains the source of a misfire to me...

Cheers
Ron Kwas is offline   Reply With Quote
Old Aug 17th, 2018, 02:26   #13
Pigeon
Volvo-loving biker
 
Pigeon's Avatar
 

Last Online: Feb 3rd, 2019 06:24
Join Date: Sep 2006
Location: All alone in the crazy city
Default

I think Ron's on the right track... I don't know these units myself (they're the sort of thing that if I want one I can knock one up for nothing out of bits I've got lying around, so I have no reason to buy a commercial unit) and there seems to be next to no information about them on the web (in particular, no circuit diagrams of the unit itself as opposed to of how to wire it in, and I can't find any decent photos of the circuit board), but I can find enough to raise a few suspicions:

They give me the impression that they were basically designed for 12V systems, and the "OK for 6V" stuff is there because they have been found to run on 6V well enough most of the time that the cases where they don't can be blamed on deficiencies of the car's existing electrics (which would be more or less true in a technical sense, too, but misses out that a 6V system would be much more likely to exhibit those deficiencies in such a way as to mess the thing up than a 12V one would).

They appear to be microcontroller-based devices (from the couple of crappy low-res photos I did find of the circuit board) and I would hazard a guess that the digital circuitry runs internally off a 5V rail, not 3.3V, because they incorporate a MEMS vacuum sensor and those are nearly all 5V devices. A 12V car electrical system should pretty much never suffer enough of a voltage sag to make a 5V regulator drop out, but a 6V system is probably hovering on the verge of it all the time, and I can't see anything beyond a 100uF capacitor to help the unit ride out a sag. An excursion big enough to affect the internal regulation would only need to cause the 5V line to drop momentarily below the internal "power good" threshold of either of the two microcontrollers (the "obvious" one, and the one in the pressure sensor) to cause them to reboot, and while they were rebooting there would be no spark for a few engine cycles.

It might help to hang a 10000uF or so capacitor between the unit's positive supply terminal and earth, and feed it via a Schottky diode. OTOH on a vehicle like this where mechanically-compatible 12V versions of all the electrical items are readily available through their use on later models, there comes a point where sticking to 6V becomes unjustifiable hairshirtery, and if it was my car I'd more than likely conclude that that point had been passed.
__________________
Pigeon's Nest

Be kind to pigeons
Pigeon is offline   Reply With Quote
The Following User Says Thank You to Pigeon For This Useful Post:
Old Aug 17th, 2018, 10:50   #14
arcturus
arcturus
 
arcturus's Avatar
 

Last Online: Today 09:21
Join Date: Mar 2006
Location: Sagres Portugal
Default

Hi I passed on Pigeons remarks for comment and here is the reply

Frank Bontenbal

9:23 AM (24 minutes ago)

to me
Hello George,

Please stop reading all these forum nonsense.
Al kind of people they do think how it works.....

We designed the electronics for the distributors ourselves, and we are a team of electrical engineers. So we know what we are doing.
We sell these distributors (also for 6 Volt) for the last 15 years.
Thousands of cars are running perfect on 6 volt.

For your information, we use a voltage step up converter to guaranty a stable 5 volt power supply for the microprocessor. Also when the unit will be supplied with only 4 Volt.....
So this is not the case....

Please return the ignition and we will find out if something is wrong.
__________________
life's too short to drink bad wine
arcturus is offline   Reply With Quote
Old Aug 17th, 2018, 14:03   #15
arcturus
arcturus
 
arcturus's Avatar
 

Last Online: Today 09:21
Join Date: Mar 2006
Location: Sagres Portugal
Default

Hi Pigeon and thanks for taking an interest.
Re' your statement
there comes a point where sticking to 6V becomes unjustifiable hairshirtery,
There is much more to converting to 12V than simple alternator battery etc,as I'm sure you know.
Dynamo, starter, regulator, coil, wiper motor, heater motor, fuel gauge, relays but to name a few. Even if I obtained a 12v fuel gauge and wiper motor, fitting them as I'm sure you know, would,unless you are a fully paid up member of the "limbo" club, would involve removing the dash which necessitates the removal of the wind screen, so it's not "hair-shirting"
Then there is also the matter of originality, not important to everybody but important to me.
__________________
life's too short to drink bad wine
arcturus is offline   Reply With Quote
Old Aug 17th, 2018, 18:00   #16
Pigeon
Volvo-loving biker
 
Pigeon's Avatar
 

Last Online: Feb 3rd, 2019 06:24
Join Date: Sep 2006
Location: All alone in the crazy city
Default

Thanks, that's interesting. Such a step-up converter was something I was specifically looking for when I searched for photos of the circuit board, but I didn't see any sign of it; although I could only find crappy low-res photos that were too small to be as informative as I wanted, such a thing would usually betray its presence by using an inductor, which would be a sufficiently distinctive component that I'd still expect to be able to pick it out. I guess they must have used a switched-capacitor converter instead, which doesn't use any such easily-distinguished components.

Re originality, of course this is a personal choice, and I must admit that my views may be coloured by the 6V system on my bike, where there is not the option of fitting a 12V generator from a later model and I wish there was
__________________
Pigeon's Nest

Be kind to pigeons
Pigeon is offline   Reply With Quote
Old Aug 17th, 2018, 18:29   #17
arcturus
arcturus
 
arcturus's Avatar
 

Last Online: Today 09:21
Join Date: Mar 2006
Location: Sagres Portugal
Default

We don't have many pigeons here but I do feed sparrows
__________________
life's too short to drink bad wine
arcturus is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 16:01.


Powered by vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.