Lots of smoke after 5k revs! Please help.

[rs-ross]

Hi,

Yesterday I was accelerating hard in 2nd gear and the whole rear windscreen filled with smoke. I then tried accelerating in other gears and there was less smoke but it seemed to be on the overrun as opposed to accelerating. I took the car out again tonight to test it and noticed there was little to no smoke now when accelerating, none on the overrun. It only seemed to smoke when accelerating past 5k revs.

The oil level is still perfect and hasn't moved since I serviced it a couple of months ago, and there's no gunk around the oil filler cap. There's also a slight splutter from the exhaust when idling. This hasn't seemed to effect the performance at all. I couldn't say what colour the smoke is as I only have access to it evenings during the week.

I predominantly use the car for very short journeys 4 times a week (5 minute journeys) and it returns around 27mpg which is quite low, although I imagine this is due to the short journeys unless there may be some underlying fueling issue?

What could be the possible causes of the spluttering and smoking? Any suggestions would be great!

 

[jesus]

Was the engine up to temperature?

 

[MG cup]

Possibly just water in the exhaust with the winter weather/condensation. Allow to warm and give it some to clear it out which is what probably happened the other night when you seen steam/smoke.

 

[MartinR]

normal

 

[rs-ross]

The engine was at normal operating temperature. In fairness I don't often floor it due to the short journeys, but yesterday it was a bit of a longer trip. I'll be interested to see at the weekend what colour the smoke is, but hopefully like you guys have said it will only be temporary and the system has just cleared itself out.

 

[rs-ross]

There's not much smoke anymore but now the emission warning light is on, and flashes if I go above a certain rev range! It also feels like there's a real loss in power and the car is very shakey.

Am I right in thinking this could be caused by a number of different things; spark plugs, coil pack, ht leads, cat, injectors, sensors etc? What would be the most likely one to cause the symptoms the car has as I've heard even a diagnositc test wouldn't be able to pinpoint the issue?

 

[Dan]

Hmm I have heard of the front lambda sensor making these sorta symptoms happen before.

Does it idle ok?

 

[aucky]

RE smoke, Its likely to be water blowing out of the exhaust, which has built up due to your short journeys.

The low pressure behind the car throws it all onto the rear windscreen.

 

[lemonnobby]

As said water out the exhaust 182 are prone due to the exhaust

 

[rs-ross]

Idling isn't too bad, isn't erratic but it does sound a bit rattly and there's a slight hesitation.

The smoke issue seems to have subsided now, it's more the fact the emission warning light is on and there's no power. As you accelerate, particularly from low revs, it's very shakey and the power isn't there.

 

[Dan519]

if the light is flashing, that signifies a "destructive misfire" usually either a dead injector, or liquid down a sparkplug hole.
You'll need it to be plugged in to identify the exact fault

 

[Dan]

Where are you from?.

 

[martynzs]

Mine does this, completely normal - 99% sure it will be steam, does it condense on the rear window?

 

[rs-ross]

it only flashes sometimes, most of the time it's solid. I'm based in Essex so may take it down to a garage for diagnostics, unless I could use one of the handheld codereaders to get the same result if it's just gonna be a generic error code?

 

[Dan]

Hmm mine a few times when I 1st fitted my decat then it stay solid and has done for a long time.

A code reader will give you a fault code also worth buying as they come in quite handy whilst owning a Clio lol

 

[montana]

Is it smoke or steam?

If its white = steam, but if it was blue = oil, black = air filter, spark plug etc.

The lumpy idle when warm is fine:approve:

 

[rs-ross]

Is it smoke or steam?

If its white = steam, but if it was blue = oil, black = air filter, spark plug etc.

The lumpy idle when warm is fine:approve:

it was white so I think just steam.

I checked the spark plugs and noticed all were fine and no water or debris in the cylinders. The spark plug nearest the oil filler cap did seem to have a lot of black carbon deposits on. Any ideas what this could indicate?

 

[mr.pink87]

Overfuelling/misfiring on this cylinder. Check injector, spark plug, HT leads.

 

[rs-ross]

Overfuelling/misfiring on this cylinder. Check injector, spark plug, HT leads.

Thanks for all the suggestions guys.

I changed the spark plugs for new NGK ones as these were getting old anyway, and also swapped the ht leads and coil pack for a second hand set I had but still no joy.

Regarding the injectors, what's the best way of testing these? If the engine is running do I just unplug the wiring plug from each injector one at a time, or do I need to actually remove the injector completely? And what should I be looking for to determine if one of the injectors is faulty?

 

[Kyle 86]

it only flashes sometimes, most of the time it's solid. I'm based in Essex so may take it down to a garage for diagnostics, unless I could use one of the handheld codereaders to get the same result if it's just gonna be a generic error code?

Where abouts in essex are u fella?

 

[MG cup]

Thanks for all the suggestions guys.

I changed the spark plugs for new NGK ones as these were getting old anyway, and also swapped the ht leads and coil pack for a second hand set I had but still no joy.

Regarding the injectors, what's the best way of testing these? If the engine is running do I just unplug the wiring plug from each injector one at a time, or do I need to actually remove the injector completely? And what should I be looking for to determine if one of the injectors is faulty?

This will work, only if you have a misfire at idle or under no load. As said, unplug electrical connection on injector while running and listen for an audible change in engine note, if no change when removing it point's towards a fault on that cylinder. Same applies with HT lead's.