What Causes 'Reduced Engine Performance' message?

[Sirjames]

Hi All,

New to the forum, but not new to Volvos- used to have a V40 ages ago! Anyway, just got a V50 1.6d (08, 2008 model) and had it for about a week now. All good until yesterday when the 'i' light lit up on the dash and the message 'Reduced Engine Performance' came up on the display. If I stop the car and restart it, the message clears and the car can be driven normally, but it's done this about 5 times now! Does anyone know what might be causing this (or what to check) and how I can stop it??

Thanks in advance,

James

[TimS]

I had this message when my V70 D4 was 5 days old. Unlike yours however, the message didn't clear.Dealer said it was a faulty oil pressure sensor.

[Sirjames]

Thanks Tim- will have a look at that

[hitby]

Fwiw, when I was test driving mine it popped up with this error. The dealer said it was bad fuel and changed the fuel filter. I went on to buy it and I haven't had it happen again in nearly 10k miles. Might be a cheap option that could sort it.

[coughlanc]

As above I had this appear on my S60 D5 several times a week or so back. Fuel filter cured it. Not saying that this is the problem for sure as there are loads of things that could cause it, but it's a cheap part to "shotgun" at it and you might be lucky. Ideally you need to pull an ECM error code to stand a better chance.

[puddles]

I have had a lot of trouble over this the last couple of months, the fact is unless you plug car into a code reader you could be clutching at straws. This could be as simple as a blocked DPF pipe to a fault with turbo not giving the engine the speed it needs. You need the codes to investigate where the trouble is coming from, I found 3 issues with my car a broken probe at the exhaust temperature sensor, a split air filter intake pipe and DPF needed a run to clear it, the code reader even so it never put the engine light on give 3 codes to look into and each code had its value. That is the only warning I got reduced engine performance, if you get Anti skid warning you are looking more at EGR related problems, I have the 2009 v50 I hear 2010 to 2012 have more clear warning symbols. You need the OBD11 reader to find the codes otherwise your just clutching at straws because it can be more then one issue, usually like this time cost a few pounds and time to correct, but it is not always that lucky but if you get any warning light it needs investigating especially if it is the DPF because ifn't it will cause more damage in the long run leading to expensive repairs.

[SwissXC90]

Originally Posted by Sirjames

All good until yesterday when the 'i' light lit up on the dash and the message 'Reduced Engine Performance' came up on the display. If I stop the car and restart it, the message clears and the car can be driven normally, but it's done this about 5 times now! Does anyone know what might be causing this (or what to check) and how I can stop it??

There are literally hundreds of causes

You won't know what it is until you connect diagnostics and read out the fault codes stored in the vehicle

Then you can narrow the fault down to eg fuel, air, electrical, timing, mechanical, exhaust, lubrication, cooling... etc etc etc

To stop the fault you need to identify the fault and then fix the cause of the fault. Either do it yourself, or let a trained, experienced professional do it for you.

Your car is very smart.
Be equally smart and use a code reader or a professional.
Don't guess. Guessing costs money and time.

[puddles]

I have read many answers to this problem all varying and each one right in its own way, so what is the problem? Can I share an experience which may help you to understand why there is no easy solution but investigation to why this as come up, five months ago this came on my 2009 Volvo V50 and went out a few second late, it did this few times till I put redex injector cleaner in and for 3 months had no trouble, there was a bigger problem then just putting cleaner in the fuel, 3 months later a couple of weeks before my child broke of school this message came up again this time with engine warning light and car going into limp mode. I plugged in my code reader cancelled codes which allowed my car to drive normal for a while. I did this till my child broke of school and I had time now to look into this.

First thing I noticed soot all over the engine and there was 3 codes high air intake, overheating EGR and code I had to look up on the computer DPF, looking in I found a split from turbo to intercooler Hose so replaced that and noticed oil in a air filter showing turbo seals had gone so decided to replace turbo, 80% of turbo hoses and oil strainer, car started to drive better no more engine warning light but a warning anti skid light come on, looking at code reader EGR so decided to replace valve and cooler, car started to drive better but reduced engine speed light continued to come on with on code the one I had to look up on computer DPF high temperature, I took car for a long drive but a lot of soot coming out of exhaust and didn't cure the problem.

I decided to buy a new DPF filter and I did and for five weeks no trouble all codes cleared, sadly last week reduced engine performance message came up again, after further investigation the exhaust temperature sensor probe had broke off and air filter to turbo hose was split, for the sensor the code reader showed high voltage when put in computer information lead to the sensor, replaced that and that problem cured but engine reduced performance message is still coming up so waiting to receive the hose, I can't see any other faults so I am lost if this doesn't work as over £1,300 new parts as gone into putting this right. I blame this on ignoring earlier warning signs and Turbo and EGR failure was caused by overheating due to a block DPF so don't ignore the warning even if it goes off and doesn't come on for a few months as redex wasn't a cure.

You will need a code reader as even so it will come up with DPF there will be another code leading you near to a related problem, check for soot around engine which is showing a split hose, there is no one solution it starts by a blocked DPF which if ignored will cause other problems. Yes it can be as simple as a split hose and as complicated as a overheated engine. Once new parts have been fitted you will need a code reader to update ECU as if you don't delete codes the EGU will still think it got these problems, sorry I haven't got no easier answer, like I said over £1,300 doing all the labour myself. Each part I replaced had to be replaced and problems was caused by overheating and the two parts which later went I didn't replace so putting old parts back on is a gamble.

[puddles]

Going back to about May I got this message on my car and thought I cured it with Redex because I got no problems till July, I kept running car till my child broke off school by then I was getting Engine reduced performance, Anti skid warning and engine light was on, so please don't ignore early warning signs. I ended up replacing Turbo because oil in art filter and 90% pipes, now engine light and anti skid lights where on. I replaced EGR valve and cooler and now was only getting engine light, so I replaced DPF and full Exhaust.

For five weeks no problems car driving as it should and then suddenly engine reduced performance light come on, I investigated and found two more faults Exhaust temperature sensor end had snapped off and there was a split in the Turbo to air filter hose a hose I never replaced. I put a new temperature sensor in but still got engine reduced performance, replacement Hose come and fitted it an now no lights car driving fine. DO NOT IGNORE EARLY WARNING IF THIS LIGHT COMES ON INVESTIGATE IMMEDIATELY, IT CAN BE AS SIMPLE AS A LOSE CONNECTION, SPLIT IN THE HOSE PIPE ETC, if you do ignore it then it will lead into major faults. Even if the light comes on then goes off again look into it. It cos me just over £1,300 and that was just for parts as fitted all the parts myself, if had to have in garage could of been looking at £3,000 to £4.000.

There is no single answer to this I have read reviews where it as been a lose battery terminal to major problems like mine Turbo and DPF failure, I was told by a mechanic I knew all the damage was caused by a blocked DPF which overheated other parts causing damage. I was told if I had of took notice of early warning took car for a long run it would of cured the problem but running the car with the fault damaged other parts like overheating the EGR system and Turbo, in some extreme cases even blow engines. The OBD2 reader will lead you to the fault, it may come up with 3 codes for 1 fault as for the split pipe it came up with air high intake, DPF and electrical but when replaced the pipe all these issues vanished, do one fault at a time the ones you can clearly see like a split hoe or a lose connection, if problem still there you need to look for signs like oil in air filter, blocked DPF etc. But it needs seeing to as it will lead to greater damage and higher repair costs, I know its a pain and confusing but nothing simple. I hope this helps and avoids high costs for you.

[Annette456]

I have had this problem with my Volvo s40 1.6 diesel. It was showing some warning signals like this reduced engine performance and abs service required? This would happen intermittently and when a diagnostic was done a lot of faults were showing? Acceleration pedal was one. A month later my alternator completely failed! This could be the route of the problem? If having these problems it may be the alternator and I would recommend getting it checked. I’ve not had one sign up now it’s driving great!! Hope this helps 👍🏻🙂