DEFENDER2.NET - View topic - Lazy start and rough idle when cold.

↓ Advertise on Defender2 ↓

Home · FAQ · New Posts · My Posts · PMs · Search · Members · Map · Calendar · Profile · Donate · Register · Log In

Home > Tdi > Lazy start and rough idle when cold.

Page 1 of 2

Print this entire topic ·

Mean Green

Member Since: 15 Sep 2011
Location: South Ayrshire
Posts: 278

Lazy start and rough idle when cold.

I am looking for suggestions - my 200tdi 90 cranks for ever before it splutters into life. Then it idles rough and 'hunts' for several minutes.

It has a new lift pump and recently changed injector pump. The battery is good and has also been on the C-tec charger to make sure.

In my head it feels like it is a fuel starvation issue - as if the fuel had drained back to the tank and had to be sucked back up to the injectors before it will start. (probably over simplistic, but it feels like it wants to start but doesn't have any fuel).

Probably a related issue - there is a fair amount of white smoke and smell of unburnt diesel when it first starts. Once is it going it runs fine.

27th Dec 2023 3:26pm

Retroanaconda

Member Since: 04 Jan 2012
Location: Scotland
Posts: 2552

First thing to check is the fuel leak-off lines on the injectors, either perished hose or loose banjos depending on age. Very common on Tdis, and causes this issue if left for more than a few hours.

27th Dec 2023 4:04pm

Mdm

Member Since: 11 Sep 2013
Location: Sunny Lancashire
Posts: 1528

was the injector pump rebuilt?

easiest way to double check if fuel pipes are drawing air is feed from a small bottle of fuel in the engine bay. if it starts every time this way you know you have an issue on the feed side of things.

if not then pump or up stream of that bit or on the return side

27th Dec 2023 5:47pm

8619simon

Member Since: 05 Nov 2016
Location: North Wales
Posts: 229

1995 Defender 110 300 Tdi CSW Epsom Green

Re: Lazy start and rough idle when cold.

Mean Green wrote:
I am looking for suggestions - my 200tdi 90 cranks for ever before it splutters into life. Then it idles rough and 'hunts' for several minutes.

It has a new lift pump and recently changed injector pump. The battery is good and has also been on the C-tec charger to make sure.

In my head it feels like it is a fuel starvation issue - as if the fuel had drained back to the tank and had to be sucked back up to the injectors before it will start. (probably over simplistic, but it feels like it wants to start but doesn't have any fuel).

Probably a related issue - there is a fair amount of white smoke and smell of unburnt diesel when it first starts. Once is it going it runs fine.

Is the timing OK? I had the same symptoms especially the white smoke on start up which then disappeared after a few minutes. Turned out the timing was slightly retarded.

27th Dec 2023 7:35pm

Mean Green

Member Since: 15 Sep 2011
Location: South Ayrshire
Posts: 278

Thanks for the suggestions. I will start with timing and work out from there.

The timing was checked after the engine was re-installed during the re-build, but wont hurt to double check.

27th Dec 2023 8:00pm

johnlad

Member Since: 18 Dec 2023
Location: Blackpool
Posts: 32

Mine was like that when the glow plugs had all failed.

28th Dec 2023 9:42am

Fossil

Member Since: 23 Aug 2015
Location: Bolton
Posts: 13

1997 Defender 110 300 Tdi CSW Coniston Green

I would agree, glow plugs have to be a suspect and are easily checked for power getting to them, and continuity

28th Dec 2023 10:40am

Mean Green

Member Since: 15 Sep 2011
Location: South Ayrshire
Posts: 278

Can someone sense check my thoughts on the 200tdi timing, it has been a long time since I last did this and cant exactly remember the details.

Am I right in saying that for the timing to be right, there are three things that can be checked...

1. the TDC line on the pulley should line up with the casting on the crankcase
2. the timing pin should slip into the slot on the FIP
3. the timing pin should slot into the slot on the flywheel.

I started by lining up the pulley and TDC line - but the slot on the flywheel was not alingned with the wading plug hole and the pin would not go into the FIP. So i lay underneath looking up into the wading plug hole and had someone turn the engine until I could see the slot. When this was lined up, the pin also slipped into the FIP, but TDC was about 20mm or so away from the casting mark.

Am i right in thinking that this would suggest that the timing belt has either slipped or has been misaligned when fitted and to fix it is basically a timing belt change ??

6th Jan 2024 11:32pm

bodstruck

Member Since: 09 May 2020
Location: Wiltshire
Posts: 784

If it was a timing issue would it not run poorly all the time?

You may have eliminated the glow plugs as a cause already but the symptoms you describe are exactly the same as i had on my Puma some while ago. New glow plugs solved it.

7th Jan 2024 9:05am

julian

Member Since: 17 Feb 2017
Location: Devon
Posts: 53

1994 Defender 110 300 Tdi CSW Alpine White

My vote is on drain back. The hole could be anywhere from the injector leak offs to a poorly sealing olive on the lift pump tails.

I always advise making up a bit of fuel line with clear nylon pneumatics pipe so as you can physically see any air. Failing that any way of connecting the return from the back of the IP to a short hose that you can dunk under the fluid level in a clear (coke) etc bottle and watch for air bubbles.

To me your symptoms sound just like something not sealing up quite right and the hole not being big enough to cause issues when running, but just large enough to cause drain back.

12th Jan 2024 12:26am

Chris86

Member Since: 15 Jul 2014
Location: South Yorks
Posts: 755

Rough Idle

Hello,

Does the rough idle and smoke clear altogether?

We have had a similar issue on a 300tdi, the keyway on the crank pulley was worn so the engine was able to minutely retard and advance itself, just fractionally.

Made for lumpy idling when starting, when driven "normally" under load it was fine, then if you idled for a long-ish period or spent a long period coming down hill on engine braking the issue would return.

Was a pain to track down.

Chris

12th Jan 2024 2:02pm

Mean Green

Member Since: 15 Sep 2011
Location: South Ayrshire
Posts: 278

So had a minor disaster.

I have owned the 90 for 25years this year and it occurred to me that I cant remember ever changing the glow plugs (largely because it never really needed them and started on half a turn of the key everytime).

So given the advice above, I thought, might as well change them for an easy fix... whats the worst that can happen!!! .. so it turns out the worst that can happen is a sheared glow plug - half of which is stuck in the head. So it now needs stripped down and the head off to get the remains of the glow plug out.

22nd Jan 2024 7:02pm

custom90

Member Since: 21 Jan 2010
Location: South West, England.
Posts: 19579

That sucks, that’s a real concern with glow plugs it really is.

When was the fuel filter last changed? Diesel$ Live$ Matter. ⛽️🛢️👨‍🔧🧰⚙️ RED, WHITE & BOOST! 🇬🇧

22nd Jan 2024 7:17pm

julian

Member Since: 17 Feb 2017
Location: Devon
Posts: 53

Mean Green wrote:
So had a minor disaster.

I have owned the 90 for 25years this year and it occurred to me that I cant remember ever changing the glow plugs (largely because it never really needed them and started on half a turn of the key everytime).

So given the advice above, I thought, might as well change them for an easy fix... whats the worst that can happen!!! .. so it turns out the worst that can happen is a sheared glow plug - half of which is stuck in the head. So it now needs stripped down and the head off to get the remains of the glow plug out.

I've been driving mine with a stuck tip for some time. I keep thinking it will shoot out at some point, but it has not.

I doubt yours will move at all, but worth soaking in wd-a-like and then going for a spirited drive before pulling the head?

23rd Jan 2024 3:01pm

blackwolf

Member Since: 03 Nov 2009
Location: South West England
Posts: 16886

2007 Defender 110 Puma 2.4 DCPU Stornoway Grey

There are kits and tools available for the removal of broken and stuck glow plugs, it is a very common problem.

The principle of operation is as described here (not that this article describes an OM606 though).

https://www.instructables.com/How-to-remove-Broken-Glow-Plugs/

Another explanation:

23rd Jan 2024 3:37pm

Page 1 of 2

All times are GMT + 1 Hour

Jump to

< Previous Topic | Next Topic >

Posting Rules

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum