Black smoke with exhaust and egr valve smoke in engine

[Welshy_Pete]

I just got my peugeot 306 hdi 99% done all the parts cheap and done by my self and afew friends. I just fitted the last part needed the slam panel everything fine. But now something serious has started a nightmare. I also drove the car 10miles before all this and it was driving fine. But abit of black smoke when the turbo kicks in. Also wen your foot right down. Its allways done this also on tick over reving it.

I think the car run out of diesel cause I was on a hill. It just wouldn't go up the hill so I put some more diesel in the car it then moved fine.

Big problem black smoke you cant see out the back window! Also there no power in the car it struggles like hell. I dont think I can get the turbo to come on when driving.

The car felt like its been going slower recently sluggish. But when I first got it was flying around like a bat out of hell.

The car start up fine, ticks over fine. It doesn't smoke on tick over left running. But god knows wats going on its no good for the road unless Im mad max to get rid of the bad guys!

Its just black soot coming out the exhaust. There no blue, white or oil from the exhaust.

Just been outside in the car with bright LED torches they show up everything. The egr valve there alot of black smoke comes out of that unit?

The egr valve I have you can see a bar in the middle. There like a valve moving up and down it stays near the top 1/4 posistion then rev goes in abit?

306 hdi 90bhp

[CitroJim]

Pete, in any diesel, much black smoke suggests a lack of air resulting in incomplete combustion of the fuel charge.

In your case it sounds like the engine is very simply being strangled...

A choked air filter can cause this and so too can a collapsed turbo pipe. One or more of the rubber pipes may look OK at rest but when revved you may find it is being sucked flat and thus stopping airflow. A seized turbo can cause this but that's rare.

Other causes can be a badly duff MAF sensor (the lump between the airbox and the concertina pipe leading to the turbo). Is it connected? For a test you can disconnect the MAF sensor and see if that changes anything. Normally though a duff MAF sensor just causes the car to run sluggishly...

The EGR valve can be disabled by pulling off it's vacuum pipe and plugging off the end of the pipe so that vacuum does not escape. I don't think the EGR is the cause though, just a symptom of a blockage...

That you can see smoke coming out of it suggests you may possibly have a partially choked exhaust. The cat may be badly choked.

Is yours a 110 with an intercooler? A big hole or blockage in the intercooler or its pipes can cause your problem too.

[Welshy_Pete]

Pete, in any diesel, much black smoke suggests a lack of air resulting in incomplete combustion of the fuel charge.

In your case it sounds like the engine is very simply being strangled...

A choked air filter can cause this and so too can a collapsed turbo pipe. One or more of the rubber pipes may look OK at rest but when revved you may find it is being sucked flat and thus stopping airflow. A seized turbo can cause this but that's rare.

Other causes can be a badly duff MAF sensor (the lump between the airbox and the concertina pipe leading to the turbo). Is it connected? For a test you can disconnect the MAF sensor and see if that changes anything. Normally though a duff MAF sensor just causes the car to run sluggishly...

The EGR valve can be disabled by pulling off it's vacuum pipe and plugging off the end of the pipe so that vacuum does not escape. I don't think the EGR is the cause though, just a symptom of a blockage...

That you can see smoke coming out of it suggests you may possibly have a partially choked exhaust. The cat may be badly choked.

Is yours a 110 with an intercooler? A big hole or blockage in the intercooler or its pipes can cause your problem too.

All the 306 hdi 90bhp dont have a intercooler. Mine all standard at the moment.

[Welshy_Pete]

This gets more strange I checked everything again the car has had a loop system put in to bypass egr. So I put those pipes back to normal and the car running perfect.

Ive cleaned the egr valve on the outside to see later on any leaks. But at the moment nothing at all.

All the smoke has stopped now out of the exhaust and egr valve.

So how come the car dont like the loop system strange?

[spider]

Examine the air filter and all intake pipework then , I'd concur it may be as simple as insufficient air.

[Welshy_Pete]

Examine the air filter and all intake pipework then , I'd concur it may be as simple as insufficient air.

Just got anther update now.

[Welshy_Pete]

Pete, in any diesel, much black smoke suggests a lack of air resulting in incomplete combustion of the fuel charge.

In your case it sounds like the engine is very simply being strangled...

A choked air filter can cause this and so too can a collapsed turbo pipe. One or more of the rubber pipes may look OK at rest but when revved you may find it is being sucked flat and thus stopping airflow. A seized turbo can cause this but that's rare.

Other causes can be a badly duff MAF sensor (the lump between the airbox and the concertina pipe leading to the turbo). Is it connected? For a test you can disconnect the MAF sensor and see if that changes anything. Normally though a duff MAF sensor just causes the car to run sluggishly...

The EGR valve can be disabled by pulling off it's vacuum pipe and plugging off the end of the pipe so that vacuum does not escape. I don't think the EGR is the cause though, just a symptom of a blockage...

That you can see smoke coming out of it suggests you may possibly have a partially choked exhaust. The cat may be badly choked.

Is yours a 110 with an intercooler? A big hole or blockage in the intercooler or its pipes can cause your problem too.

If you take the vacum pipe of I will also have to block the bit that goes in the master cylinder t piece as well?

It has the loop bypass done on mine it didn't like it. So Im thinking would the vacum block work or not?

But its running fine with everything normal so its hard to say wat to do.

[CitroJim]

Pete, I'm not at all familiar with this loop bypass you speak of. How is it plumbed.. Can you give us a good description?

yes, when ever you pull the vacuum pipe from the top of the EGR valve it's vital to plug the loose pipe end so that all other vacuum systems continue to function normally. Brakes especially!!!

[Welshy_Pete]

Pete, I'm not at all familiar with this loop bypass you speak of. How is it plumbed.. Can you give us a good description?

yes, when ever you pull the vacuum pipe from the top of the EGR valve it's vital to plug the loose pipe end so that all other vacuum systems continue to function normally. Brakes especially!!!

The pipes were looped going back in to circulation or something. So Ive put it all back to standard how it should be.

If you take the vac hose of what do you do with the plug solinoid leave that plugged in or out?

thanks

[CitroJim]

If you take the vac hose of what do you do with the plug solinoid leave that plugged in or out?

Leave the electrovalve (solenoid) plugged in Pete. If you disconnect it the ECU becomes a bit flustered and raises a fault...

[Welshy_Pete]

If you take the vac hose of what do you do with the plug solinoid leave that plugged in or out?

Leave the electrovalve (solenoid) plugged in Pete. If you disconnect it the ECU becomes a bit flustered and raises a fault...

What diffrence will I see with it disconnected?

Apart from clogging up the exhaust or engine.

Also the pros and cons if any?

thanks

[Welshy_Pete]

Hello any ideas to my last questions?

thanks

[Welshy_Pete]

If you take the vac hose of what do you do with the plug solinoid leave that plugged in or out?

Leave the electrovalve (solenoid) plugged in Pete. If you disconnect it the ECU becomes a bit flustered and raises a fault...

What diffrence will I see with it disconnected?

Apart from clogging up the exhaust or engine.

Also the pros and cons if any?

thanks

Just thinking if to block the valve or not......