Felicia Fast Idle and Idle rpms

[Cepheuz]

what is the fast idle (rpms at cold startup) and idle speed for a skoda felicia 1.3 (carb, and MPI)

wanted to adjust mine, but have no point of reference

[DGW]

Autodata CD2 lists data for four 1.3 engine codes for the Felicia, all of which were available for your car's year. The idling speeds quoted for the engine codes are:

135 - 42kW (57hp) - 800+/-50

135 - 43kW (58hp) - 800+/-50

135M - 50kW (67hp) - 760-820 - Not adjustable

136M - 40kW (55hp) - 760-820 - Not adjustable

[KenONeill]

With carb and Kettering arc, my mates and I always used to set idle like this:-

Change any ignition components that were due to be changed.

Set points gap.

Take car for a drive and get engine hot.

With engine running, swing dissie to get highest idle speed.

Adjust idle mixture screw on carb until you get the slowest revs the engine idled cleanly at.

[djaychela]

what is the fast idle (rpms at cold startup) and idle speed for a skoda felicia 1.3 (carb, and MPI)

wanted to adjust mine, but have no point of reference

"Carb and MPI"?

There's no adjustment of the idle speed available on the MPI.

[Cepheuz]

"Carb and MPI"?

There's no adjustment of the idle speed available on the MPI.

yes, i know there is no adjustment for the MPI, witch would give me a good reference to where my Carb model should be at warm up, that is why i asked what is the fast idle speed...

i know the idle speed is 850rpm, i alredy set it, and i have Autodata CD2 and Vivid Workshop manual, plus Haines Carb manual, but none of them give me the Fast idle for my car.

all i have found ithe the hayne for forman 135 witch would be 2300 rpm, i think this is a little too much, and wanted to compair it with the MPI fast idle.

so please, tell me at what rpm is you engine when you first start it on the mornings,

sorry to bother, without a 5 gas exaust analyser and without a oxigen sensor is har to tune a carb for all the rpm rage.

[Cepheuz]

With carb and Kettering arc, my mates and I always used to set idle like this:-

Change any ignition components that were due to be changed.

Set points gap.

Take car for a drive and get engine hot.

With engine running, swing dissie to get highest idle speed.

Adjust idle mixture screw on carb until you get the slowest revs the engine idled cleanly at.

doing that my engine would knock or ping a lot, even with 95 RON gas, plug it feels like the clutch is slipering (but is not, just feels like that)

i've set the ignition timing, dwell and point gap, all acording to stock data, just need the fast idle, is not a matter of adjusting the engine, but tuning the carb stock.

[felicia16v]

the engines fitted with a carb had an automatic choke system which did run them up to around 1800>2000 rpms when cold and gradually dropped it down as they warmed up.. ign should be around 10 deg with no vac at hot idle.

the mpi engines dont really alter from cold rpms to hot as the ecu runs the fuelling to suit

[TeflonTom]

There's no adjustment of the idle speed available on the MPI.

there is :yes: but you cannot do it manually, you need to do some vag-com jiggery pokery, it is only a very limited range of speeds it can be adjusted to, iirc it's +/- 150rpm

[markjmd]

what is the fast idle (rpms at cold startup) and idle speed for a skoda felicia 1.3 (carb, and MPI)

wanted to adjust mine, but have no point of reference

Cepheuz

According to my copy of Autodata Carburettors 1992 Edition, fast idle on the 1.3 Favorits (135 and 136) with Pierburg carbs is 2300rpm. The carb model is listed as "2E3, identification number 4301-360.6". The adjustment instructions for the Jikov carbs don't make any mention at all of a fast idle speed, but they have a manual choke so I'd be surprised if that's what's fitted on the Felicia.

Cheers

Mark

[J242]

my 1.3 MPI idles at 850, fast idle is around 1100 (cold mornings, etc). everything standard, hope this is useful

[Cepheuz]

my 1.3 MPI idles at 850, fast idle is around 1100 (cold mornings, etc). everything standard, hope this is useful

thanks,

i went ahead and set fast idle to 2300rpm, after doing this (and setting choke valve gap correclty) i cooled the engine for 4 hours, it started @ arround 2000rpm, then went to 1500rpm and after a while it settle to 900-950rpm (my normal idle) so all is good,

i know idle should be lower, but it shakes and with this setting is smooth.

[Thefeliciahacker]

On 03/07/2010 at 02:45, TeflonTom said:

there is :yes: but you cannot do it manually, you need to do some vag-com jiggery pokery, it is only a very limited range of speeds it can be adjusted to, iirc it's +/- 150rpm

I know its a veryyyy old topic but please can you elaborate how this is done
I thought of aplying 12v to the ac ecu pin in order to trick it into thinking the ac is on and therefore raising the idle.
BUT if it is possible to do it through vag com i would happily try

[RicardoM]

22 minutes ago, Thefeliciahacker said:

I thought of aplying 12v to the ac ecu pin in order to trick it into thinking the ac is on and therefore raising the idle.

I would be VERY careful with applying any voltage on any pin of the ECU. Unless you have a spare one ready.

As for the "jiggery pokery" mentioned, I am not aware of such possibility. It is more important to diagnose WHY the idle rpm is not normal in order to find the real CAUSE instead of fooling the ECU by tweaking an input parameter.

[Thefeliciahacker]

1 hour ago, RicardoM said:

I would be VERY careful with applying any voltage on any pin of the ECU. Unless you have a spare one ready.

As for the "jiggery pokery" mentioned, I am not aware of such possibility. It is more important to diagnose WHY the idle rpm is not normal in order to find the real CAUSE instead of fooling the ECU by tweaking an input parameter.

Its not actually low but rather the dash seems to display it low. 500 rpm when under normal operation. And around 800-900 when cold. 

Sadly I don't have a tachometer to verify. The real reason is that when the car is under a high load on low rpm (1100-1200) and you suddenly press the clutch while releasing the throttle the rpm will drop down to almost 100 (on the dash) and the car will try to bring them back up, this happens with both lpg and gas. While the success rate (of avoiding a stall) with gas is 100% with lpg it is around 60%. 

Note when ac is on and idle is a little higher none of these happen. 

Please see the last part of this vid as you can clearly see the low "displayed" rpm

 

Edited 23 August, 2019 by Thefeliciahacker

[KenONeill]

I'm going to stay well clear of saying that you can/how you modify the ECU to "increase revs" when the AC is on.

 

What I can say is that AC does cause an additional load on the engine, which will pull the idle speed down and demand a squeak of throttle to get it back to normal.

[Thefeliciahacker]

1 hour ago, KenONeill said:

how you modify the ECU to "increase revs" when the AC is on.

I mean it is done automagically by a certain pin that goes HIGH 
But i was wondering what can be done through vag-com

[KenONeill]

On 23/08/2019 at 15:32, Thefeliciahacker said:

I mean it is done automagically by a certain pin that goes HIGH 
But i was wondering what can be done through vag-com

Nothing in VAG-COM I think. OTOH, based on what you've said I suspect that, if you know the pin-outs, there will be a wire from the live side of the AC switch feeding the pin that's switched Low to High.

[RicardoM]

@Thefeliciahacker

13 hours ago, Thefeliciahacker said:

While the success rate (of avoiding a stall) with gas is 100% with lpg it is around 60%. 

Having LPG installed should have been an information important enough to share in this context. Also having the engine details clearly showed under your avatar helps a lot. See my car description to the left.

 

The tachometer works perfectly fine. It is the fast idle and normal idle rpm that are very low. As I've mentioned in my last post, you don't tweak the ECU when something goes wrong. It is usually the sensors that send wrong data to ECU. There is a saying, "garbage in, garbage out". In your case I see two probable reasons:

1. The intake vacuum is somehow disturbed by the LPG installation.
2. The LPG installation is somehow connected to the ECU causing issues.
3. The combined sensor (Intake Air Temperature + Intake Air Pressure) is dirty.

[KenONeill]

@RicardoM Agreed 110% about the LPG kit. I was working on the basis of solving an idle speed drop when air conditioning was switched on, and had no idea about the LPG. It's not even the same problem!

[RicardoM]

10 hours ago, RicardoM said:

In your case I see two probable reasons:

Make it three.

[Thefeliciahacker]

17 hours ago, RicardoM said:

The tachometer works perfectly fine. It is the fast idle and normal idle rpm that are very low. As I've mentioned in my last post, you don't tweak the ECU when something goes wrong. It is usually the sensors that send wrong data to ECU. There is a saying, "garbage in, garbage out". In your case I see two probable reasons:

1. The intake vacuum is somehow disturbed by the LPG installation.
2. The LPG installation is somehow connected to the ECU causing issues.
3. The combined sensor (Intake Air Temperature + Intake Air Pressure) is dirty.

Well I did not mentioned the LPG as the car had this issue long before the LPG was installed,
This was apparent by the un-educated attemps to improvise a solution to increase the idle.
The previous mechanics had wrapped zip ties onto the metal part of the thorttle body in a desperate attempt to get the idle higher (make this thing stop in a more open position)
Just for the record when I got the car I replaced all rubber hoses and make sure there were no vaccum leaks present, today I replaced the MAF/IAT sensor with a known good working one.
The TB was also replaced today with a good known one.
Also the crank position sensor got replaced today with a known good one (and that actually made the car run smoother and accelerate better)
And I again made sure there were NO vaccum leaks.
But still couldn't this just be a sligtly miss-reading tacho?
Still waiting on my vag-com to make a factory reset using Motordiag Simos Manager
Any opinions are more than welcome
 

Edited 24 August, 2019 by Thefeliciahacker

[RicardoM]

13 hours ago, Thefeliciahacker said:

And I again made sure there were NO vaccum leaks.

How did you do that?

13 hours ago, Thefeliciahacker said:

But still couldn't this just be a sligtly miss-reading tacho?

No, in your video I could hear clearly the rpm is low. The engine is struggling to idle. The tachometer works by converting the pulses from crankshaft sensor -> ECU into voltage using an integrated circuit (frequency-voltage converter). Nothing fancy. The voltage feeds a coil that creates a magnetic field that in turn rotates the needle.

13 hours ago, Thefeliciahacker said:

The previous mechanics had wrapped zip ties onto the metal part of the thorttle body in a desperate attempt to get the idle higher (make this thing stop in a more open position)

We're talking about high tech in there...

[Thefeliciahacker]

1 hour ago, RicardoM said:

How did you do that?

I did that using two methods. 

First I sprayed contact cleaner everywhere around all rubber hoses and connections. 

And secondly while the engine was running I put my hand on to the TB and the car stalled. And after stalling it held a vaccum for approximately 10 seconds. 

Which is good based on that some air is going to leak from the oil cap small port. 

Also doesn't a vaccum leak usually cause high idle due to leaning of the engine? 

1 hour ago, RicardoM said:

We're talking about high tech in there...

Sadly yes and who knows what else they would have tried. 

Some of them even think that the felly has self adjusting valves 😂. 

[RicardoM]

9 hours ago, Thefeliciahacker said:

Some of them even think that the felly has self adjusting valves 😂. 

Yeah, also self-repairing engines.😎

 

The last solution is to reset the TB properly with Motordiag Autocomsoft SIMOS Manager.

[Thefeliciahacker]

8 hours ago, RicardoM said:

Yeah, also self-repairing engines.😎

 

The last solution is to reset the TB properly with Motordiag Autocomsoft SIMOS Manager.

This is what I am planning to do when I get my kkl cable. 

And I will make a video tutorial about it in English as I have already done one for the TB cleaning.