Peugeot 405 1.9td very smoky and idle jumps

[TimDonovan]

Hi im new here because,
I have a peugeot 405 1.9td 1993 which I saved from a pentioner who wanted to scrap it.
To my problem, the car was running great and I did an oil change, coolant change, Thermostat change, glow plugs changed, fuel filter change. Just basic Service after standing quite a while.
So one day it started smoking quite excessively, it always liked to smoke on cold starts, but now it never really stops, what symptom came with the smoke is like a little rev surge which happens all out the rev range and at idle. To mention never really sooted or smoked black, much rather a grey smoke.
I can feel it having the little surge driving too.
I have had the injectors checked but that didn't resolve the problem.

Here you can hear and see the rough idle.

[Oldpug]

Provided nothing has been altered on the injection pump, or it’s not loosing any coolant. All it needs is a good thrashing.
Add these to the fuel tank https://www.forteuk.co.uk/product/advan ... treatment/ and give it a long run at high revs. Those old turbo XU Diesels are bullet proof, but they do not like lack of use or slow runs.

[TimDonovan]

Thanks for the reply,
I had the fun screw turned up a quarter turn but as soon as my problem started I turned it back to oem speck.
I was thinking the same with giving it a good run but the little surge rev happens while driving too, and is acomplished with this little knock or dodgy noise.
Yeah the coolant is a thing I didn't have a chance or the balls to drive it a lot in it's current state, I'll put the thing back together and take it for a drive.
I had valve adjustment in mind could that be causing the problem, I'd just wouldn't think valves would change that fast, I'd expect that to happen more gradual.

[TimDonovan]

Thanks for the reply,
I had the fun screw turned up a quarter turn but as soon as my problem started I turned it back to oem speck.
I was thinking the same with giving it a good run but the little surge rev happens while driving too, and is acomplished with this little knock or dodgy noise.
Yeah the coolant is a thing I didn't have a chance or the balls to drive it a lot in it's current state, I'll put the thing back together and take it for a drive.
I had valve adjustment in mind could that be causing the problem, I'd just wouldn't think valves would change that fast, I'd expect that to happen more gradual.

[Oldpug]

When you say valve adjustment, do you mean valve tappet clearances? If so I would not consider it, they are shimmed and never need altering unless the cylinder head has been dismantled.
If a good thrashing does not cure the fault? It could be the knock sensor, but throwing parts at it is not the way, it needs an ECU diagnostic fault code check. Try and find an “old school” Peugeot Specialist who has the old Peugeot Diagnostic Tool.

[CitroJim]

Being a 1993 model, this will have the fully mechanical VP20 pump and therefore no knock sensor or ECU to diagnose.

I'd also not thrash the b0**0cks off of it until the cambelt has been changed, given it's history. If it snaps on these engines then t's game over.

The smoke. When you say grey, is that a light, almost white smoke or dark, almost black? Also, does it smell of unburned diesel?

It may be just a lack of air due to an obstructed inlet tract somewhere between the air filter and turbo inlet. It's not unknown for the large rubber pipes to loose their integrity and squash themselves flat when the engine is revved, thus starving the engine of air.

I take it the air filter itself is clean and the inlet to the air filter housing is clear?

A good test is to run the engine with the turbo, intercooler and all hoses disconnected from the inlet manifold so the engine runs normally aspirated... You should see no smoke under such conditions... You will hear a very loud induction roar too!

Mis-set valve clearances usually result in hard starting with lots of white smoke. As OldPug says, valve clearances rarely need attention.

[TimDonovan]

Hi I was on holiday and I am back on it now.
I started it naturally aspirated as I had parked it, it really surprised my by how well it started and it was running and not smoking up the place as bad, as usual.
So I carefully, started to drive and suddenly I heard like a squeaky noise and really loud like knocking. Had a check but didn't really see anything that may have caused it.
It starts fairly well but I get a massive knocking noise from the inlet.
I've just mounted the intercooler and boost pipes back on. Haven't started it yet tho.
I read up in my hanes manual and I can't stop thinking of my cold start solenoid, in the manual it says the cable should be slack, which mine isn't. Is that a reasonable suspicion?
I'm starting to think its a headgasket or even a bottom end bearing failure,but I can't really explain why it should do that so suddenly.

Please let me know your thoughts, I'll start it now and try and film it running with the turbo all connected up again.

[CitroJim]

The cold start advance mechanism can be dismissed as it only advances the timing a little and not enough to cause your issues. It's worth checking the pump static timing though...

Also, more critically, before doing that (or anything else), do check the cambelt is properly timed. It is easy to get it one tooth out and just one tooth in error can account for your symptoms... The cambelt timing MUST be absolutely correct. Check by pinning the crank and the cam and pump sprockets. Haynes tells you how.

[TimDonovan]

Right, I didn't manage to start it yesterday because I left the ignition on while working on it.
I recorded it running and the smoke. And yes I had the feeling it was smelling quite a lot of unburnt diesel.
I also though about the pump timing, but same as with timing, it really shouldnt just jump out of timing for no reason should it.
I'll try and get my hand on a dial gauge and check the pump timing.



Here it is running. I'm thinking of giving it a drive, maybe it clears out. I'm also gonna do an oil pan seal and I might just have a look at the crank on the lift at work. And do a Co test.

Thanks for your replies and if you notice anything in the feel free to tell me.

[TimDonovan]

Just an Addition to your Previous posts.
Timing belt looks still OK, not brilliant but ok.
I had the engine running NA as seen in the video, and it was still smoking quite bad.
What worries me is the knocking I got out the intake when it idles rough, which Is why I was thinking worn cam or valve adjustment.
Also I'm thinking the crank case ventilation, could that be causing problems?

[CitroJim]

Check the cambelt timing first before proceeding any further

[moizeau]

As Jim says, start with basic checks before over thinking things which can lead you down a rabbit hole. While you're checking the cam belt timing, check to see if the cambelt crank sprocket is secure. Depending on which version of woodruff key set up you have (single or double) it's easy te misset the inner key so it doesn't fully locate. It tightens and everything seems fine and can take several years of vibration to eat it's slot, and start rattling around thus adjusting the timing.

[CitroJim]

Good call on the pump woodruff key and sprocket security Pete!

[TimDonovan]

Ok I'll check the Timing, I already wanted too but the pulley bolt on the crank is on there TIGHT.
I took it for a drive tho, it drives pretty well under load but decelerating you can really feel the engine having rpm surges, fighting the brake.
Also downshifting it really disliked
I put some injection cleaner in it, the really bad smoking got better.
Anyone got experience with good timing belts and pulleys and stuff?
Thanks for the replies up until know

[darbuck]

Gates are the most reliable and consistent quality wise. Continental/contitech are close second in my opinion.i don't trust anything else