Flashing 'Engine Management /Exhaust' Light
Discussion
Hello, please bear with me I'm new to'gassing'. I currently have a Fabia mk2 (2007) 1.2 HTP 70 which has full dealer service history from new.It has done 34k miles. Never had any issues until this weekend where the engine management light flashes. Here's the symptoms......
A couple of people have said to take it for a 'good run', but not sure what they mean by this.
I welcome any ideas & appreciate any help you can offer please.
- Only ever happens at speed on the Motorway when its been at the constant speed for a while (around 3000 revs). Engine Management Light flashes & car goes into limp mode.
- When I pull off the motorway, stop & restart the engine, the light goes out. If I stick to 'A' & 'B' roads light stays off. It only happens when on motorway 60-70mph.
- No faults are showing when it's 'plugged' in to computer.
- Car runs totally fine at all other times. Good MPG, no misfire.
A couple of people have said to take it for a 'good run', but not sure what they mean by this.
I welcome any ideas & appreciate any help you can offer please.
The light actually flashes....as opposed to lighting up and staying lit ?
Are you sure it's the management light ?
And when you say no codes when plugged in...are you 100% sure it is no codes, as opposed to the person trying not having full access ?
What equipment are they using to try and retrieve any information ?
But the flashing light is odd...not sure I've seen to many flash.
Are you sure it's the management light ?
And when you say no codes when plugged in...are you 100% sure it is no codes, as opposed to the person trying not having full access ?
What equipment are they using to try and retrieve any information ?
But the flashing light is odd...not sure I've seen to many flash.
Hi stevieturbo, thank-you so much for replying. Yes, the light just flashes. (It's the orange light in the shape of an engine). When I stop & restart the engine the light goes out. It only comes back on when I drive 60-70mph (2800-3500 revs) for 10 minutes or so.
Other than that, it drives, revs & ticks over perfectly.
Not sure exactly what kit my mechanic has. He's been very reliable over the 20+ years I've used him & he seems to keep up to date with technical kit.
The only thing i've done differently prior to this happening is put some different fuel in. It was running perfectly & incident free on 'Tesco Momentum 99ron'.
Two days before the fault showing i filled up with 'Esso Premium 97ron' from a Tesco express.
Could this change cause a problem??
Other than that, it drives, revs & ticks over perfectly.
Not sure exactly what kit my mechanic has. He's been very reliable over the 20+ years I've used him & he seems to keep up to date with technical kit.
The only thing i've done differently prior to this happening is put some different fuel in. It was running perfectly & incident free on 'Tesco Momentum 99ron'.
Two days before the fault showing i filled up with 'Esso Premium 97ron' from a Tesco express.
Could this change cause a problem??
A flashing MIL means the EMS thinks there is a misfire occurring at that moment that is significant enough to result in tailpipe emissions exceeding the mandated pollutant limits. If you upload the stored OBD codes, the system will tell you if the misfire is on a single cylinder only or on all cylinders. if it is only one, you can swap parts between cyls (like coil packs) to see if the misfire moves, and hence identify the faulty part.
Misfire is detected by the EMS looking at changes in crank shaft speed when cylinders fire (or more accurately, a lack of change of crank speed when a misfire occurs). In some cases, the system can be fooled by things like unbalanced wheels/tyres, worn CV joints, knackered engine mounts, or even loose / damaged crank sensors and reluctor rings etc.
However, there is a good chance that the engine is actually misfiring, so first thing i'd do is take a good look around the engine electronics and the plugs etc, looking for water ingress, cracked HT leads or coil packs. It's certainly not unusual for coil packs to start to breakdown only when hot, like during a motorway run at higher engine speeds/loads etc
Misfire is detected by the EMS looking at changes in crank shaft speed when cylinders fire (or more accurately, a lack of change of crank speed when a misfire occurs). In some cases, the system can be fooled by things like unbalanced wheels/tyres, worn CV joints, knackered engine mounts, or even loose / damaged crank sensors and reluctor rings etc.
However, there is a good chance that the engine is actually misfiring, so first thing i'd do is take a good look around the engine electronics and the plugs etc, looking for water ingress, cracked HT leads or coil packs. It's certainly not unusual for coil packs to start to breakdown only when hot, like during a motorway run at higher engine speeds/loads etc
Tubs and Flo said:
...when its been at the constant speed for a while (around 3000 revs). Engine Management Light flashes & car goes into limp mode.
What do you mean by "limp mode"? If you get a sudden loss of power, chances are it really is misfiring, possibly on two cylinders. In the case when cylinder pairs (1-4 or 2-3) are misfiring it doesn't necessarily feel very rough at all.Tubs and Flo said:
Hi AER,
By 'limp mode' I mean what the owners manual describes as "The engine management system selects an emergency programme which enables you to drive to a garage...using a gentle style of driving".
So I believe the loss of power is enforced by the 'emergency programme'.
I understand what you mean by limp (home) mode, but how do you know this has happened? What are the signs? A warning lamp? A change of engine feel? etc...By 'limp mode' I mean what the owners manual describes as "The engine management system selects an emergency programme which enables you to drive to a garage...using a gentle style of driving".
So I believe the loss of power is enforced by the 'emergency programme'.
The car was driving along perfectly, when all of a sudden the engine light started to flash.
After the flashing started, the car started to slow down as if there was a limiter on it.
Pressing on the accelerator would not increase the speed or revs, it seemed limited at around 40mph.
(after looking in the owners manual, I concluded the car had gone into emergency mode).
I pulled off the motorway at next junction, turned the engine off. Turned engine back on & no light.
Carried on to my destination on main roads & car drove perfectly. On my return journey I went back on the motorway & what I described above, happened all over again.
Prior to this there were no signs of a problem, no misfire, car drove perfectly & still is on main roads.
I am sticking to main roads for now & car is still driving perfectly.
My local mechanic has plugged my car into vag-com & no faults show. He's checked the car over & changed the plugs as these were passed their best. He could find nothing else that was wrong.
I tried motorway again with new plugs & exactly the same thing happened!
After the flashing started, the car started to slow down as if there was a limiter on it.
Pressing on the accelerator would not increase the speed or revs, it seemed limited at around 40mph.
(after looking in the owners manual, I concluded the car had gone into emergency mode).
I pulled off the motorway at next junction, turned the engine off. Turned engine back on & no light.
Carried on to my destination on main roads & car drove perfectly. On my return journey I went back on the motorway & what I described above, happened all over again.
Prior to this there were no signs of a problem, no misfire, car drove perfectly & still is on main roads.
I am sticking to main roads for now & car is still driving perfectly.
My local mechanic has plugged my car into vag-com & no faults show. He's checked the car over & changed the plugs as these were passed their best. He could find nothing else that was wrong.
I tried motorway again with new plugs & exactly the same thing happened!
Hi Le TVR
Technically it is the exhaust warning light, but so many components affect it. Including plugs, coil, bad wire etc.
I've taken it for a good 'hard workout' today to burn off the Esso fuel. Filled it back up with Tesco Momentum 99Ron & the problem seems to have gone!!??
I'll see how it goes over the weekend.
Technically it is the exhaust warning light, but so many components affect it. Including plugs, coil, bad wire etc.
I've taken it for a good 'hard workout' today to burn off the Esso fuel. Filled it back up with Tesco Momentum 99Ron & the problem seems to have gone!!??
I'll see how it goes over the weekend.
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