Hello everyone, as the title itself says. The tachometer on my Favorit started going crazy but I can't see where the problem lies. Here are a few words on the issue; When the car is idling and you press the throttle everything seems fine until the engine reaches some 2500 RPM, the tachometer then jumps all the way to 8000 RPM and bounces back. While driving the car every time I shift gears the tachometer bounces up and down to about 3500 RPM (I shift gears anywhere from 2000 to 2500 RPM) How can I fix this issue? Any help is valuable!

Cheers

Edited 19 April19 Apr by Joja2k

You could try checking your engine earth strap for a start: add a good jump start cable as a second earth and see if that helps?. Failing that I would guess that there may be a fault with your ignition amplifier if it has one, then possibly some fault with the tachometer, or the printed circuit board that it sits on, but that would be a job for an expert: which I am not..

Check earth cables, wires and connections from battery, engine, dash dials, also check the battery terminal posts and inside terminal post clamps are clean, then they are tight to posts. God to start with clean secure supply from battery. After that it could be a connection or wire, I don't know the wire for the tach but ignition issues seems a reasonable suggestion, it might often be accompanied by other signs though, check from spar plugs, back (or from ignition switch to plugs if you prefer). Might just be a dirty or "dry" connection to dial.

Long term Favorit (or Felicia) owner's would know more and better, perhaps it's common issue now, or perhaps not.

Good luck, let us know how you get on.

20 hours ago, nta16 said:

After that it could be a connection or wire

In Felicia the speedometer wire has a square nose which goes 1cm inside the teflon plastic socket and the 2 ''ears'' they ''click'' and hold it place.

is the nose comes out for a reason you hear a characteristic ''Tzzzz'' sound as it bounches.

In Favorit is like this

https://www.ekodiely.sk/galeria/produkty/max/2022/07/20/38792204178-1658301702.jpg

more robust connection.

https://scdn.autodoc.de/catalog/categories/600x600/10661.png

At tachometer

https://media.pazar3.mk/Image/727ff982-5a49-4920-a626-fdfef011e110/20210805/false/False/1280/1024/skoda-favorite.jpeg?noLogo=true

the suddenly prm jump from 2500 to 8000 (it's the limit) means gauge proplem or possible connection (plug) issue.

On 20/04/2025 at 01:04, nta16 said:

Check earth cables, wires and connections from battery, engine, dash dials, also check the battery terminal posts and inside terminal post clamps are clean, then they are tight to posts. God to start with clean secure supply from battery. After that it could be a connection or wire, I don't know the wire for the tach but ignition issues seems a reasonable suggestion, it might often be accompanied by other signs though, check from spar plugs, back (or from ignition switch to plugs if you prefer). Might just be a dirty or "dry" connection to dial.

Long term Favorit (or Felicia) owner's would know more and better, perhaps it's common issue now, or perhaps not.

Good luck, let us know how you get on.

Right, recently I have changed the distributor since the old one was on it's last legs. The new distributor is a NOS Bosch unit, so I have no doubts about bad part quality. After I replaced the distributor I also checked that it was in phase and within it's margins 5 +- 2 degrees. The same day that I changed the distributor the tachometer went nuts, but not immediately, a few hours later. And honestly the only thing that I can remember about the tachometer being suspicious was that before the distributor change, here and there it would jump above 4000 RPM during gear shift, but that's about it, actually it did get stuck at around 3000 RPM when I was driving the car and in higher RPM. Could the distributor change have anything to do with this? So far my thoughts are that it might be the ignition amplifier (module).

Cheers!

Edited 21 April21 Apr by Joja2k

Personally I don't trust something just because it's got a Bosch badge or label on it but no doubt some Bosch stuff is good and if you have tested it and it's OK then fine. You could test again to make sure it remained fine.

Yes of course changing the distributor might have caused an issue or highlighted an existing issue, that might be the new part showing up the old parts(s) or (visa-versa) or you could have disturbed something in doing the change. There was a fault or issue before the change though.

When changing parts did you check are connections were clean, secure and protected, same for wires, no pins corroded or with stuff on them or bent or broke, a slight bit of crud can make all the difference.

I'm not an electrician or mechanic or expert in anything so I possibly not know much take more caution and perhaps care than those those that know more (which is most).

On my older cars with more basic ignition systems I would also check spark plugs, HT leads (more naughty spray test than resistance reads) the rotor arms and perhaps dissy caps could cause all sorts of issues. Very rarely, unless new, would the (single, old style) coil play up. Then of course there was the voltage regulators and for some the alternator.

I forget the details of the type of ignition system on your car, the others have told and explained it to me but I've not retained the info (without a photo to look at).

Like all the other parts the ignition amplifier module, or its connections or wires, could be faulty but all things need to be checked and tested rather than just suspected, unless a part(s) are so inexpensive and trustworthy you don't replace them for the sake of it (a mate changes spark plugs every annual service as he gets them at such a low price). He would swap a (single old style) coil as they are low priced and difficult to check for full consistent reliable function in use (unless you have a dyno or meters you can wire up whilst driving the car), of course the risk is new modern made parts being worse than worn old parts.

I have often found it is the simple basic items that have been overlooked that were or are the cause - not always of course and I'm not saying any of these in your case - but a number of times I've been told "no it won't be that" or "that's new" or "I've checked that" (HT leads used to be a favourite, I was even caught out myself by them).

One way to help check new parts is to refit the old part and see what if any difference it makes, perhaps to test readings too.

Edited 21 April21 Apr by nta16

Hello everyone,

After testing and probing I decided to change all of the contacts for the tachometer, the "condition" improved so to speak. The tachometer now only goes wild at 3500 RPM (it was going wild at 2000-2500 RPM before changing the contacts) I have come to the conclusion that it's either the ignition amplifier (module) or the tachometer itself. Any thoughts?

Ps. As I have understood the tachometer is getting an impulse from the ignition coil to read the rotations of the engine and it is then connected to the ignition amplifier. So given that it could also be a "chain reaction" (meaning that both the ignition coil and the ignition amplifier are at fault).

I have checked the spark plugs and the ht leads, both were replaced (and are good) and are fresh (by the previous owner last year, but I have replaced the spark plugs myself after buying the car)

Cheers!

Edited 24 April24 Apr by Joja2k

1 hour ago, Joja2k said:

So given that it could also be a "chain reaction" (meaning that both the ignition coil and the ignition amplifier are at fault).

Could be both or neither just changing parts can run on to be an expensive and slow process to find a resolution. You would have to include wires and connectors as parts too. Best to test the items first. If you decide to replace them hold on to the old parts for a good while (up to year or two perhaps) in case the new parts turn out to be lower quality than the ones you took off.

You could also look for anything that could interfere or cause issues, something trapped or rubbing or something added to the car causing issue(s), incorrect or poor wiring or connections.

I had a set of HT leads that looked good so I left them to change later rather than as I normally do change to know good ones and I got a very indeterminant engine cutting out but easy to restart, turned out to be a high voltage backtracking to the distributor cap and causing havoc, it cost me more than a good set of quality HT leads to find this out on an old Sun diagnostic machine with someone who knew what he was doing with it.

Let us know how you get on and what you find the solution to be.

Hello everyone,

As of today the only thing I haven't changed is the connection to the board itself. I have checked all of the cables a couple of times and they are fine (not damaged anywhere). I have changed the HT leads, the ignition amplifier and the ignition coil. After all of those changes the tachometer is working a lot sharper (it was kinda sluggish before). But the problem still persists (but not in as it was before, the tachometer jumps here and there again but only when I let go of the throttle). I haven't had the chance to test it while driving the car yet. But yesterday before the changes I was driving the car and in the higher RPM's when the tachometer began going crazy, the engine started to behave like it was misfiring (there was a lot of push and pull in the higher RPMs and it also felt like something was blocking (restricting) the engine at the same time). I will test the car in motion today and leave the info later on.

Honestly, if it's not the connection to the board itself i don't know what else it could be?

Cheers!

14 minutes ago, Joja2k said:

Hello everyone,

As of today the only thing I haven't changed is the connection to the board itself. I have checked all of the cables a couple of times and they are fine (not damaged anywhere). I have changed the HT leads, the ignition amplifier and the ignition coil. After all of those changes the tachometer is working a lot sharper (it was kinda sluggish before). But the problem still persists (but not in as it was before, the tachometer jumps here and there again but only when I let go of the throttle). I haven't had the chance to test it while driving the car yet. But yesterday before the changes I was driving the car and in the higher RPM's when the tachometer began going crazy, the engine started to behave like it was misfiring (there was a lot of push and pull in the higher RPMs and it also felt like something was blocking (restricting) the engine at the same time). I will test the car in motion today and leave the info later on.

Honestly, if it's not the connection to the board itself i don't know what else it could be?

Cheers!

In short, the symptoms so far are; misfiring in the higher RPM's and the tachometer going crazy in the higher RPM's (above 2500). Could it be an engine vacuum leak?

Cheers!

15 minutes ago, Joja2k said:

Could it be an engine vacuum leak?

The symptoms in a vacuum leak (in my case) was unstable idle at low rpm and suddenly needle drooping from middle rpm to low or in steady idle.

Check that small rubber hose it's an easy task, check the connection in front (to the regulator) or in the end (intake manifold) and use tie-wraps or in the middle if there is a crack.

It sounds like possibly an ignition or electrical issue to me. Are all earth on car electrics ad electronics (ignition) clean, secure and where appropriate protected. Anything that earths through the engine check that they fully can and that the engine (and battery) earths are also clean, secure and where appropriate protected.

Same for connection(s) to board - clean, secure and where appropriated protected.

I think we have covered before - not assuming a new part is fully working correctly or installed correctly or that the previous part was correct, or fully working or installed correctly. Something like a frayed unseen wire inside it's insulation can cause problems when under more load (electric or physical) or when something is hot or cold or vibrating from car movement. These are why you do road tests after repair or replacement work, what works when the car is stationary may not, or not fully work, when the car is in actual use on the road. Even a rolling road isn't as good s an actual drive in various conditions (and over longer time periods).

Has anything (devices) been added to the car that might cause some sort of interference, any changes from factory standard on electrical wiring, has the wiring been varied from factory type.

Are you working on the car in a garage (heated and de-humified or holes in the roof) or outside in the frost, rain or snow. Any water, or other fluid(s) leaks on the vehicle.

That's me out of ideas.

Hello again,

After testing the vehicle on road with both the new parts fitted and the old parts refitted. I can say that the car behaves better with the old parts (at least it is more consistent per se).

Any suggestions?

Videos of the rides coming soon, just need to upload them

Cheers!

Edited 30 April30 Apr by Joja2k

Here are the links;

PLEASE NOTE: the screeching that is heard in both of the videos is coming from the steering wheel, the base needs to be lubed!

New parts fitted:

Also check the video description!

Old parts refitted:

Also check the video description!

Again as I said I have checked all of the wiring and it looks good, the engine does not have an earth strap (or at least I'm dumb because i cannot find it). All of the connections are secure and clean (I cleaned them).

I would say that overall the car is behaving better with the old parts refitted but the problem persists!

Any suggestions?

Cheers!

Edited 30 April30 Apr by Joja2k

My quick thoughts, though I did get a little distracted by the temperature gauge (D.FYLAKTOS will know more about that) and the creaking of the seatbelt(?) was a dominant sound to me.

• How do the new parts compare to the old parts, are they the same make, model and exact type

• does the engine normally sit at (a very steady) 1,000 rpm at idle (when warmed)?

• what is that red thing around the ignition barrel?

• how does the car and engine sound and feel when the rev counter flicks (you mention misfire)?

• it may well be somethings else making the sound so I am not sure, does the engine "tappety" (ticky)?

Slightly off subject, are you ever able to get the car on to an open road and get the revs and speed higher, lower revs can be good for fuel and engine saving but it does mean that things can get clogged up a bit so the occasional "Italian tune-up" blow-out (the cobwebs) runs are required. Previous models had a green marked section on the rev counter to show where the engine was best suited to use. Of course "Italian tune-up" runs and where you have the engine in the rev range depend on the condition and health of the engine and car and you would not push the engine or car if the engine and whole car are not in reasonable good condition and health.

Be interesting to see what @D.FYLAKTOS and @Thefeliciahacker think of those videos being Felicia owners and more knowledgeable.

16 hours ago, Joja2k said:

the engine does not have an earth strap (or at least I'm dumb because i cannot find it)

A proper cable from negative pole to the car's body will do the job.

https://www.skoda-parts.com/data/items/278/5da96621b81ea_xl.jpg

1K0 971 250

The throttle body is 100% clean?

Vacuum hose is checked thoroughly?

I have Felicia but the temperature needle works one click different here in Favorit.

23 hours ago, D.FYLAKTOS said:

A proper cable from negative pole to the car's body will do the job.

https://www.skoda-parts.com/data/items/278/5da96621b81ea_xl.jpg

1K0 971 250

The throttle body is 100% clean?

Vacuum hose is checked thoroughly?

I have Felicia but the temperature needle works one click different here in Favorit.

Yeah, I do have a cable coming from the negative pole of the battery to the car's body and it's a clean connection. (I was confused because I thought "engine strap" should come out of the engine lol)

The throttle body is 100% clean (I cleaned it)

All of the vacuum hoses were inspected and none of them have holes and/or are broken, cracked anywhere. Those that were were changed by me.

Cheers

On 01/05/2025 at 10:33, nta16 said:

My quick thoughts, though I did get a little distracted by the temperature gauge (D.FYLAKTOS will know more about that) and the creaking of the seatbelt(?) was a dominant sound to me.

• How do the new parts compare to the old parts, are they the same make, model and exact type

• does the engine normally sit at (a very steady) 1,000 rpm at idle (when warmed)?

• what is that red thing around the ignition barrel?

• how does the car and engine sound and feel when the rev counter flicks (you mention misfire)?

• it may well be somethings else making the sound so I am not sure, does the engine "tappety" (ticky)?

It's not the seatbelt creaking, but the steering wheel as I wrote in the post. The base of it is rubbing against the plastic housing, so I need to lube the steering wheel.

The new parts look the same, but there's no indication on them what make they are.

The one weird thing comes to mind though. The new distributor does not have any markings on it (ie where you line it up so that you know that it's gonna hit the no 1 tdc)

I honestly thought about the distributor and I think that my neighbour, who set it up for me did it wrong, I'm gonna check that later today.

The engine sits anywhere from 900 to 1200 RPM, but usually at 1000 RPM (I lowered the RPMs on the carb, but when we went lower than approx 900RPM the engine would start "dying" So I figured that the tachometer is ****ed. The RPMs were lowered as much to the spec as I could by my ear (800 +- 50 RPM) So I think the tachometer is giving the wrong reading. After changing the distributor the RPMs kicked up by like 100 though (I think the distributor timing is off).

That red thing around the ignition barrel is like an airplane protection clip? Like they have in the cockpits.

The engine sounds like it's misfiring, there's a lot of push and pull, power loss (ie the car is not really going faster when the counter flicks) and hesitation (also on the gas pedal there is a lot of movement backwards and forwards (like it's jittering).

Could the incorrect distributor timing cause misfiring and all of this nonsense that's happening with the car?

Cheers!

Edited 2 May2 May by Joja2k

52 minutes ago, Joja2k said:

It's not the seatbelt creaking, but the steering wheel as I wrote in the post. The base of it is rubbing against the plastic housing, so I need to lube the steering wheel.

Fair enough, I didn't see the note originally, perhaps I missed it or you added it latter, the noise did seem to me to be coincide with the steering wheel being moved but that's on a video over the internet not real life with you actually in the car.

Surely if there's rubbing then either the steering rod cowling is too close or the steering wheel is fitted too low or a combination of both, assuming both are factory standard and original to when car was new and not replacements. My last car had a non-original steering wheel rod and I had to cut the (plastic) cowling down to get a good fit.

With the distributor I am only used to those with no marking, set up approximately and then adjust as required, timing is set after valve clearances (CB points) and plugs have been checked and adjusted as required and before any fuelling checks and adjustments.

Don't worry too much about idle and idle speed shown on dial as long as you get smooth consistent idle after the engine has been fully warmed (engine Oil temperature above 80c and above 90c for better oil (and possibly engine) life.

Sorry on second look at vids I noticed what the red thing was.

Yes the misfiring could upset the rev counter AFASIK unless VW had things different (the fuel gauge system seemed usual over complicated VW / German set up especially for the make and model of the car at that time so I don't know how over complicated VW might have made the rev counter (Simply (Un) Clever).

I'm not sure if the setting of the distributor would cause that much of a misfire reaction but if the distributor isn't fitted correctly (I have heard of one not being fitted so that it was secure so actually moved around, also seen a cap fitted backwards, clip left off, etc.). If your distributor is a cheap one made in China then try refitting your original distributor and see if there is any difference. As I put before it could be the distributor, how it's fitted, (the rotor), the cap, (leads, plugs).

Good (landscape) photos of your engine bay might help identify things, can't remember if you have done this before but photos of (dissy) distributor, HT leads, module, coil might help.

For earthing check, as with first reply on this thread, a good temporary tester, to engine perhaps if battery to body cable has been checked, is an engine starter jump cable (parked use only of course. You can do no harm adding a permanent good quality and correct sized earth cable to the engine, or to other items if required, perhaps additional wire(s) to items that get poor earthing by factory route.

On 19/04/2025 at 21:31, Favorit Fan said:

add a good jump start cable as a second earth and see if that helps?

ETA: you can add previous photos you have put up in posts by clicking on the open-file icon on the left hand side of the grey box at the bottom of the post box.

Edited 2 May2 May by nta16
ETA:

Hello again,

I have refitted the old distributor in and set the ignition timing approximately (I don't have a timing light) And now there's no more jumping on the tachometer so far. The car is working as it should. That makes me suspect bad new distributor quality. Your thoughts?

Also if anyone knows how can I set the distributor timing without the timing light, that would be very helpfull?

Ps. The way I have approx set the distributor timing is. I turned the motor to 5 Degrees on the pulley, fitted the distributor in and turned on the car. The car was working on approx 400 to 500 RPMs. then I turned the distributor counterclockwise until the RPMs rose up to about 1000 on the tachometer (I have noticed that when the car is off the tachomter sits at some 200 to 250 RPMs on the clock, so I figured that when in motion 1000 RPMs on the tachometer should be about 800 more or less irl) then I tightened the distributor and that's it.

Cheers!

Quick new update, after restarting the car, there is now noise coming from the engine bay, but I can't decide if it sounds like rattling, knocking or pinking.

2 hours ago, Joja2k said:

Quick new update, after restarting the car, there is now noise coming from the engine bay, but I can't decide if it sounds like rattling, knocking or pinking.

The noise is coming from somewhere between the distributor and the no.1 cylinder (that's how it sounds)

4 hours ago, Joja2k said:

That makes me suspect bad new distributor quality. Your thoughts?

It sounds like you may have bought one of the many p1ss-poor, rubbish built Chinese ignition parts. Often they are just a gamble, some work fine, others work for a while then intermittent or complete fail, others still soon play up or fail. I think I put before they were so cheap the purchasers carried the old dissy in their car ready in case the new one needed swapping out - to me, having had decades of unreliable parts, not a good way of doping things. Over here many would have the old dissys refurbished, I preferred a good quality fully (top and bottom) electronic distributor, fit and forget (other than annual clean of rotor and cap posts. Costs more initially but still going reliably after (nearly) 16 years of use.

4 hours ago, Joja2k said:

Quick new update, after restarting the car, there is now noise coming from the engine bay, but I can't decide if it sounds like rattling, knocking or pinking.

I think (I might be wrong, again) that you put before that you have checked/set the valve clearances already, you have checked the plugs so now get the timing right and then check, adjust as required) fuelling. If you have not already done so make sure your engine air filter (and filter box) are clean.

Ignore the tachometer other than as a rough guide, get it sounding smooth and running at steady idle and go from there, I will leave it to others that know more for best method of setting timing, they may need to know you have a module if that wasn't standard to the factory car originally.

2 hours ago, nta16 said:

I think (I might be wrong, again) that you put before that you have checked/set the valve clearances already, you have checked the plugs so now get the timing right and then check, adjust as required) fuelling. If you have not already done so make sure your engine air filter (and filter box) are clean.

Ignore the tachometer other than as a rough guide, get it sounding smooth and running at steady idle and go from there, I will leave it to others that know more for best method of setting timing, they may need to know you have a module if that wasn't standard to the factory car originally.

Valve clearances have been checked and adjusted some 2000 km ago by myself to exact factory spec, also if by module you mean the ignition amplifier (module), no it is the factory one in the car, even though i bought a new one.

Cheers!

Edited 2 May2 May by Joja2k