Freelander TD4 "surging"

Hi to all

I’m new to this forum and to Land Rover, having recently purchased a 53-reg Freelander TD4 from a friend.

I’m entirely happy with it except for one problem, so here goes (sorry for the length of this ! )

At low speed/revs (say between 1200 and 1800 revs) and when trying to maintain a fixed speed of say 30mph, the vehicle feels like it’s not sure whether it should be accelerating or decelerating, and “surges” gently every half second or so, as if I’m gently pressing the throttle then releasing it.

If I accelerate hard, it does so very well and with no “surging”. If I take my foot off the throttle to slow down, it does so without “surging”. I only get the surging feeling when trying to maintain a steady speed. And i should mention that when the weather is VERY cold, the fault doesn't show itself for the first minute or two after starting the engine and driving off.

At speeds over 45mph it doesn’t do it, or at least I can’t feel it.

Fuel economy is fine, and performance is otherwise ok apart from the car being a bit hesitant when pulling away.

I visited my local Land Rover dealer to have it sorted out, and what a waste of time:

• They drove the vehicle and could “feel” the problem themselves.
• They hooked it up to their computer but failed to communicate with the ECU, could not explain why this was, and thus could not be sure what was causing the problem.
• They suggested that the symptoms pointed to a faulty fuel pressure regulator and also identified that some turbo hoses had “gone soft” and needed replacing.
• They also proposed that the MAF could give the same symptoms.

Such was their confidence that I agreed for them to change the hoses and fuel pressure regulator and collected the car the following morning, paying them approx £300.

The Land Rover technician had apparently tested the vehicle after fitting the parts and declared it fixed, but it was obvious to me within minutes that it was exactly the same as when I had left it with them. I returned later that day and spoke to the service guy, who apologised but explained that without being able to retrieve the fault codes from the ECU they were unable to do any more unless I was willing to fund their experiments with various replacement sensors. No refund was forthcoming and I left, feeling rather badly treated to say the least.

I have since done some reading on this forum and elsewhere and I have taken it upon myself to change the MAF (as suggested by Land Rover) but this too has proved to be wasted money.

So I’m at a loss where to go from here. Does anyone have any suggestions as to why the ECU refuses to give out its fault codes, or what might be causing the problem? Any help or comments would be much appreciated!

Thank you and regards
Chirky

Hi Chirky,
Two areas that you may consider looking at; http://www.landyzone.co.uk/lz/f9/td4-crankcase-filter-62361.html and Ming's Sticky on EGR.
Reasons? - If your crank case breather has not been changed since new (it got left off LR's service sheets!) or the EGR is blocked or it's valve's sticky then interference between the normal engine breathing/recirculation systems and the normal air flow, could(?) produce similar symtoms but it won't show on any read out.
Both relatively cheap fixes and worth doing even if they don't solve your immediate problem. :welcome2:
There are some other causes for fluctuating engine speeds linked to air con and fuel systems but that's stuff for the more experienced members to help you out with, keep the info coming and I am sure you will get the help you need.

Hi TD John
Thank you for taking the trouble to reply on boxing day! Didn't think anyone would be interested over xmas.
Is it possible to clean the crankcase filter, or is renewal the only option?
And would i be better off just disconnecting the vac line to the EGR valve (as i have read on this forum) to disable it altogether? I guess this wouldn't solve the problem if the EGR was stuck slightly open.

Do you think it's more likely to be a breathing problem, rather than a faulty sensor?

Thanks again.
Chirky

Welcome Chirky

Cleaning the EGR valve is easy enough to do if you are getting the bonnet open anyway. Apart from anything it will help with the airflow. Once unbolted and out, its an old toothbrush and degreasing fluid orpetrol or paraffin etc etc.

Crankcase filter is either the wire mesh type which is easy to clean as above, or the BMW filter which doesn't seem to suffer these problems.

Either way, its probably cheaper to clean bits and replace filters than replace the sensor in the first instance.

Merry Christmas
Dave

Hi, If you don't mind getting your hands a bit dirty then have a go at the EGR like in Ming's thread. If it is stuck you will see it's open when you take the hose off, if it's not stuck or dirty, disconnecting/bypassing it does make the car go better (did on mine) anyway. :5bdriving:
I swapped the standard CC filter for the complete BMW part and again noticed a difference. Recently someone found that you can buy just the cone part of the BMW kit rather than the whole thing and it fits onto the LR part instead of the sponge filter holder - cheaper option but keeps the old valve part (ok unless thats sticking?). :5bcheers2:
Both worth doing and cheap mods in Freelander terms - if it solves your variable speed problem a double bonus.
Happy New Year

Hi Guys
Thanks for the replies so far. I've seen the crankcase breathers on ebay for about £30 so will order one asap. Once the old one is off i can take my time to clean/soak it, ready for next time. I might wait a week or two to have a look at the egr, as i don't have a garage and it's a bit cold to be working out doors for too long (yes i know, i'm "nesh", as my wife would say).

Did anyone have any idea why the ecu refused to communicate with LandRover's computers? I'm just wondering if i'll be looking at a new ecu at some point in the future!

Regards & a very Happy New Year
Chirky

I'd get someone else to try to read it (or get a cheap generic reader - about £15 from HK on fleabay) before considering an ECU replacement and all the reprogramming costs that involves.
Anyone with a 'cheap' ODBII generic code reader will/should be able to communicate with the ECU but it will only read the generic Engine (Emmission) codes.
You do need a Test Book or L/R Licenced reader (Sykes Picavant etc.) to read the majority of the LR generic codes (ABS, SRS, G/Box etc.).
But if you can read ANY codes (or live data) using a generic reader then the main ECU is communicating ok and probably you need to try a different dealer.

You say that you changed the MAF, was it a real LR Bosch part or an OEM part?
There have been several threads complaining that 'cheaper' (and not so cheap) MAFS failed almost immediately or were worse than what they replaced?
Seems there was a flood of sub standard parts out there - even saw a thread on one person who had a dealer change the new MAF three times - buyer beware!
Not looking forward to the time when I need one - probably go the Pierburgh and Synergy route as that seens to have more reliable results.

The replacement MAF was from the same LR dealer that attempted to fix things before (the next nearest dealer was too far, but i would have preferred not to give my local dealer any more of my cash if i could have avoided it).

Thanks again for the info and the diagnostics suggestions - i'll report back once i've changed the breather.

Regards
Chirky

this sounds like a classic case of the early stages of injector fouling, i have had it twice now, from what you describe, the car runs fine at speed ,but is a pain at low load/speeds,and will eventually suffer lumpy tickover
the problem is,,,, it is difficult to find the fouled injector until it really becomes badly fouled, or the tickover is very lumpy

what is happening is the spray pattern of the injector is not correct and not being attomised correctly
maybe try some injector cleaner, it sometimes works
if you can pinpoint the faulty injector -replace it

good luck

OK - here's the latest...........
New year's day i decided to tackle the EGR, so set about removing and cleaning it. Not too much gunk inside it considering what i was expecting, and it wasn't jammed open (in fact i would say it's jammed shut!).
Looked inside the manifold with a torch and whilst it's all coated in tar it wasn't too bad. I decided to remove the boost pressure sensor and check/clean it, and ended up removing the manifold in order to access the retaining bolt. The tip was covered in tar-like muck and partially blocked, so i unblocked it with a pipe-cleaner and refitted it.

Having reassembled everything and had a test drive i can say that any improvement is marginal, almost unnoticeable, so i'm thinking john t is right about this being an injector problem.
So the plan now is to begin using injector cleaner in the fuel for a month or two and see if that improves things - i'll report back ............
Regards
Chirky

Chirky said:

OK - here's the latest...........
New year's day i decided to tackle the EGR, so set about removing and cleaning it. Not too much gunk inside it considering what i was expecting, and it wasn't jammed open (in fact i would say it's jammed shut!).
Looked inside the manifold with a torch and whilst it's all coated in tar it wasn't too bad. I decided to remove the boost pressure sensor and check/clean it, and ended up removing the manifold in order to access the retaining bolt. The tip was covered in tar-like muck and partially blocked, so i unblocked it with a pipe-cleaner and refitted it.

Having reassembled everything and had a test drive i can say that any improvement is marginal, almost unnoticeable, so i'm thinking john t is right about this being an injector problem.
So the plan now is to begin using injector cleaner in the fuel for a month or two and see if that improves things - i'll report back ............
Regards
Chirky

Click to expand...

Any update on your injectors?

I'm interested in your results too - I've had your surging problem on a nearly three year old Freelander 2, although mine was most noticeable at high speeds in 5th and 6th gear.

I had it into the garage yesterday for an electric fault, but mentioned the surging as well - and they told me they had ordered a battery and "a valve". I'll be following up on Monday to see what that valve actually is - and then whether it makes any difference!

Jim

Hi guys.

Well, funny you should enquire about my progress as i was going to post an update in a day or two......

Having concluded that john t was probably right about it being caused by injector fouling, i had a look at a few

products (Millers etc) and finally went for a tin of BG244.

See Power Enhancer HOME | Engine Cleaning | Injector Cleaner | Octane Booster for more details, although I actually bought it off ebay.

I don't do huge mileage and since adding the BG244 to a full tank i've used just over half the tank and covered

about 260 miles.

Results so far......very impressed. The surging problem has now all but gone - i occasionally think i can feel it

very slightly but that's because i'm expecting it to still be there. The real test is my wife, who always

commented on it, but who says she can no longer feel it at all. If there is still any residual effect i think the

remainder of the tank should see it off.

The BG244 itself smelled exactly like Millers diesel sport4 but seemed a bit thicker (= more concentrated ?) when i

put it in the tank. I rarely fill the tank completely, so in the long term i think i'll start using "proper"

filling stations rather than supermarkets, as i suppose it's the additives that make the likes of Shell/Esso a bit

more expensive, but it'll save me trying to add a half-portion of Millers each time i add £25 of diesel !

So, thanks to john t for his advice, and a big thumbs-up to BG244. I initially thought it would turn out to be a

waste of money, but it actually seems to have worked for me and i'm a happy bunny.

Regards to all
Chirky

Hey - that's good news!

I was about to get a can for myself, but the garage has now replaced the turbo boost control solenoid which they say caused the surging problem.

Have not tested this properly yet - will report back if any problems.

Jim

have same problem. I was told by an independant repairer it was the fuel pressure regulator wiring harness. Bought the harness today and will fit in next few days

Oh no - that's three different solutions I've read for a surging problem! :doh:

Hope yours works well for you. I'm doing a longish run tomorrow so mine will get a test then and I'll report back.

Jim

ginny said:

have same problem. I was told by an independant repairer it was the fuel pressure regulator wiring harness. Bought the harness today and will fit in next few days

Click to expand...

how much was the harness? whats the problem with them? if its the connector why the whole harness? thanks.

the harness cost £40 from a landrover dealer, it has 3 wires and is about 2 feet long. Been told it is a common fault with the connection that goes on the fuel pressure regulator

jimstrong said:

I'm doing a longish run tomorrow so mine will get a test then and I'll report back.

Click to expand...

Well, it does look as though the turbo solenoid has fixed my particular surging problem - although I'll be keeping a close eye on it, all was well today at the speeds I previously saw the problem occur.

Jim

ginny said:

the harness cost £40 from a landrover dealer, it has 3 wires and is about 2 feet long. Been told it is a common fault with the connection that goes on the fuel pressure regulator

Click to expand...

Section 6 of this 75ZT HOME mentions LR tech bulletin 00052 to replace the harness and the fuel pressure sensor due to corroded contacts. It includes part numbers.