Td5 a little down on power and lumpy idle from start

**Markf** · 27th March 2018, 01:13 PM

Hi folks,
I've got a question or two.
Bog standard unmodified D2 2000 manual Td5 with a 10p engine. EGR is still intact. Head recently replaced with an AMC head for 10p.

Since head replacement the engine has a REALLY lumpy idle for a few seconds after starting especially when cold. Much belching of black smoke while lumpyness persists when starting from cold. Lumpyness period is a bit shorter when starting from warm / hot.

It can't maintain 110kph up a local hill in top gear - it drops down to below 100kph. It used to be able to accelerate slightly up the same hill before the head replacement so it's down on power. At low revs (from idle) it's a definite slug - down a lot of power. Once the 2k RPM threshold is passed it goes a lot better. I know a Td5 just off idle is a slug but it's now a LOT more sluggish.

MAF replaced with a genuine MAF. The old one was reading about 30 or so at idle and never got beyond about 310 at full noise. The new MAF shows about 50 to 55 on my Nanocom at idle and over 530 at full noise. With the new MAF it feels as though it goes better and is definitely worse with the MAF disconnected.

MAP/IAT cleaned - it was pretty mucky but cleaning it made no difference. The readings from my Nanocom seem to indicate that it's working OK.

EGR valve cleaned and is giving no faults whereas with the old head and MAF I got EGR stuck closed or EGR stuck open faults regularly. Cleaning the EGR valve made no difference to the power or idle problems.

I've checked ALL of the hoses for integrity and there is nothing wrong with any of them including the turbo hoses. Boost modulator solenoid is new.

MAX boost is up around 1.4 to 1.6 at full noise.

Injectors were put back in the right place and Nanocom shows the correct codes in the right place.

Glow plugs tested and are OK.

Injector loom was replaced at the same time as the head. No oil in red plug. Engine loom is only about 10k km old.

Fuel pump is new and genuine.

Does anyone have any ideas what to look at next please ?

**Tins** · 27th March 2018, 01:38 PM

I was going to say injector codes, but you've covered that.

Was it like this from the moment you had the head replaced? Clutching at straws here, but could the timing chain be a tooth out? I'm not familiar enough with the mechanical side of TD5s to know if that is even possible.

**PhilipA** · 27th March 2018, 02:01 PM

Yes, agree re timing. Maybe not a tooth out but probably worth checking the camshaft timing.

I thought that may contribute, but the black smoke on start up on a stock engine is a bit of a worry.
I wonder if there is a poorly seated injector and the washer is leaking.

What are the injector balances when idling? If one shows more than say2% or so it may point to a leaking washer.
Regards Philip A

**Markf** · 27th March 2018, 02:06 PM

Originally Posted by johntins

I was going to say injector codes, but you've covered that.

Was it like this from the moment you had the head replaced?

The trip from the workshop in Morwell back to Moe was when it started - straight after the head was replaced.

Clutching at straws here, but could the timing chain be a tooth out? I'm not familiar enough with the mechanical side of TD5s to know if that is even possible.

Hmmm. That's something that I didn't even consider in my wildest imaginings. I'll have to do a bit of googling to work out what the symptoms may be and if it's even possible without wrecking things like valves, etc. I would've thought though that the symptoms of the timing chain being out world be a bit more severe. As I say, I need to research more.

**Tins** · 27th March 2018, 02:26 PM

Originally Posted by PhilipA

Yes, agree re timing. Maybe not a tooth out but probably worth checking the camshaft timing.

Is that adjustable at the sprocket? In that case I would definitely be looking at that.

**Markf** · 27th March 2018, 02:37 PM

Originally Posted by PhilipA

Yes, agree re timing. Maybe not a tooth out but probably worth checking the camshaft timing.

I thought that may contribute, but the black smoke on start up on a stock engine is a bit of a worry.
I wonder if there is a poorly seated injector and the washer is leaking.

What are the injector balances when idling? If one shows more than say2% or so it may point to a leaking washer.
Regards Philip A

Injector balance numbers oscillate a bit between -3 and + 3.

You did give me an idea though.
Yes. Oil level has risen since it was filled. and this doesn't look good.Oil drop.jpg

Poo Bum Wee

**Tins** · 27th March 2018, 04:19 PM

Originally Posted by Markf

Injector balance numbers oscillate a bit between -3 and + 3.

You did give me an idea though.
Yes. Oil level has risen since it was filled. and this doesn't look good.Oil drop.jpg

Poo Bum Wee

Bugger

**Markf** · 27th March 2018, 06:17 PM

Originally Posted by johntins

Bugger

Yeah, bugger indeed. Very, very disappointing after paying a barrow load of money for a new head and another MUCH bigger barrow load of money to get it installed.

I'm hoping that they've (VSL Morwell) only nicked an o-ring or two. I've told them what the problem is and I can't get it in until Easter Tuesday.

In my frenzy trying to diagnose the problem I did the fuel purge thing (throttle to the floor 5 times) and found three things. 1. It made no difference to the lumpy start. 2. My fuel pump is nice and quiet as befits a pretty new one. And 3. The oil level rose a couple or three millimetres.
When I pulled the dipstick to get the drop on the paper I thought that it seemed a bit thin and the nice halo around the drop confirmed it. I think that there's a LOT of diesel in the oil. Can't smell diesel but my sense of smell is almost non existent.

This little exercise has proved once again what a valuable resource this forum and its people really are.

**DazzaTD5** · 27th March 2018, 06:51 PM

I have seen many a sole stuff up when fitting injectors to a TD5, how I dunno, maybe its a touchy feeling thing ya get when working on the TD5 engine long enough. When I do them I like to whisper sweet nothings at the engine.

I'd prolly recommend only using genuine seals, both the o-ring and copper seal.

**Markf** · 27th March 2018, 09:08 PM

Originally Posted by DazzaTD5

I have seen many a sole stuff up when fitting injectors to a TD5, how I dunno, maybe its a touchy feeling thing ya get when working on the TD5 engine long enough. When I do them I like to whisper sweet nothings at the engine.

I don't go so far as whispering sweet nothings to.
I reckon the Td5 is a bloody reliable lump provided it always has clean fuel, clean oil and clean filters.
This time around it was a dealer who did the work. My guess is that they hurried the job and wrecked an o-ring or two when fitting the injectors to the head.

I'd prolly recommend only using genuine seals, both the o-ring and copper seal.

Genuine only here always. The local dealer will be doing it and they'll only supply genuine parts.

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