Technical Check Engine warning lamp on.

[thuraja]

Hi guys,
My Panda 2004 'check engine' warning lamp is on and apparently I need to replace my plugs.
Will the dash warning lamp extinguish, once I've replaced the plugs?
My mechanic mentioned something that he will need to cancel the fault tru his computer for the lamp to go out. (which means that I can never change my own plugs)
Thanks

 

[Goudrons]

The Check Engine warning light is on because the engines ECU has detected a fault or suspicious reading from one of it's many sensors.

It will have stored a code, often described as a DTC (diagnostic trouble code).
This code can be read with a scan tool via the cars on board diagnostic port and code looked up (on the internet) to help indentify what is wrong.

It's not unusual for it to take three drive cycles (three cold start-warm ups) before a Light is lit and DTC stored, this is to make certain it's an ongoing fault.
Some will turn the light off similarly, but most need to be cleared with a scan tool before they will go off (after repair)

Generally these sort of faults fall into two, it's not always just a faulty/broken sensor that all too often get the blame!

Most sensors work on a signal voltage and alter this signal voltage somehow before it returns to the ECU, so whatever alters this signal might be over or under reading or not reading anything
So a mechanical fault could be altering what the sensor reads beyond what the ECU expects to see.

Or
The sensor it's self is faulty or broken or has a wiring fault.


I doubt old sparkplugs would, on their own cause a Check Engine Light, so I think you might be a bit misled there I'm afraid.
A scan of the engine ECU is needed, once the code is read and looked up it should make it much easier to diagnose.

There are cheap, bluetooth ODB2 readers available (ebay) that use your smartphone that work reasonable well to read these codes.
Most diy mechanics will have something that will pull a code.

They generally read generic engine codes that every manufacturer uses that relate to fueling and ignition.

These tools aren't so good at reading manufacturer specific engine codes, but there aren't usually that many used on engine ECU's.

They will also not read ABS or Airbag ECUs, that is usually a different tool or a specific manufacturers combined diagnostic tool.

So get the code read, a proper diagnosis and whatever repair is needed, otherwise it's just going to come back again and again.

 

[g8rpi]

Additionally, if you are going to do your own work on the car, there is Fiat software that runs on a PC (any old laptop will do) that gives much more information than the code number or generic message that the handheld readers give. There are two packages Multiecuscan (which I prefer) and AlfaOBD. MES costs €50 for the registered version an interface (such as an ELM 327, get a "modified" one like ebay item 271275445368) costs about €25. The free demo verson of MES will tell you a lot and clear the check light. The full setup will cost you less than a lot of garages will want just to read the code and clear the light.

HTH,
Robert G8RPI.

 

[Sweetsixteen]

Most cheap code readers will clear the Mil (your check engine light) and buying one is a great investment which will save you time, worry and money.
It may be that you are not able to fix the fault yourself, but at least a code reader will give you knowledge, and this will be useful when you take your car to a mechanic.

If you choose to get a code reader and clear the light yourself, MAKE A NOTE OF THE FAULT CODE BEFORE CLEARING IT. Codes are stored for a reason, and if the same code returns later you have an ongoing fault.

 

[thuraja]

Many thanks for the replies containing very useful information. I have tried to locate this reader online but the ones I found on ebay fail to mention FIAT amongst the many cars it would fit.
I would greatly appreciate a link to one which would fit. Another thing, would this unit be left plugged in or fitted whenever you'd need to check a fault warning light?
Thanks again.

 

[g8rpi]

Hi,
I recommend the Fiat specfic Multiecuscan softwarehttp://www.multiecuscan.net/ rather than hand held reader. Try the free version first, but the registered version is only €50 (£30). You need an interface lead like ebay item 271275445368. This will allow you to look at the engine module. If you need to look at other modules like ABS and air bags you will need adaptors like 301231120324. This setyp needs a laptop to run on, but even an old Windows XP one from ebay (I got mine for free on freecycle

) will do the job.
The handheld units (ebay item 271819306958 for example) only connect to the engine module and give far less information. The information they give is generic to all makes, whereas Multiecuscan gives model specific information and many more functions.

Robert G8RPI.

 

[Goudrons]

One of these
http://www.ebay.co.uk/itm/Mini-ELM3...tic-Tool-UK-/271623595403?hash=item3f3e07258b

It will read all the basic, generic DTC's and I've used one of these many times, it worked on our 2007 Panda no problem.

I've never needed more for engine DTC's, it's very cheap and with a bit of practice and knowledge it can be used to dig down on a fault.

It will come with software for a bluetooth device, (tablet, smartphone) but I have found the App Torque Pro simple and easy to use from Android devices.
http://www.ebay.co.uk/itm/Mini-ELM3...tic-Tool-UK-/271623595403?hash=item3f3e07258b

It's powered via the cars OBD2 port, so you can leave it attached if you want and display all sorts of engine related specs to your phone, but there is no need really.

 

[Sweetsixteen]

Remember that if you get what Goudrons suggests, which is a useful piece of kit, you will also need the software and a laptop/tablet to interrogate it, and you can't leave it plugged in unless you leave the screw-on cover off. The cover does not fit when the device is connected.

An Autel Maxiscan will do a similar job, and you can get these off Ebay for around £9 delivered. They are a stand-alone code reader, and work well with small Fiats, but do not read transmission or ABS faults.

 

[DigDug]

Here's the lot of cables that will allow you to read and clear all codes on the car with the aforementioned MultiECU scan software

[ame]http://www.amazon.co.uk/dp/B005E8RTSO/ref=pd_luc_rh_sbs_02_01_t_img_lh?_encoding=UTF8&psc=1[/ame]

 

[thuraja]

Thanks for all the very informative replies, I appreciate all your support.

 

[Sweetsixteen]

As everyone above.

Just bear in mind that the bluetooth dongles mentioned will not work if you're running an iPad.

 

[thuraja]

Ok,
The problem has gone away...
All that was needed was a fuel injector cleaner !! I poured a bottle of Slick 50 into the fuel tank and within 2 days, It was back to normal.
Sometimes it pays to start with the simple things.
Thanks to everyone who tried to help, was much appreciated

 

[Most Easterly Pandas]

Ok,
The problem has gone away...
All that was needed was a fuel injector cleaner !! I poured a bottle of Slick 50 into the fuel tank and within 2 days, It was back to normal.
Sometimes it pays to start with the simple things.
Thanks to everyone who tried to help, was much appreciated

I doubt it'll have been that simple, I've never had a MIL appear thats just required a bottle or snake oil to resolve.

Hopefully it'll stay away however.