Td4 Lack of power at 70mph - fixed !

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In the past someone suggested to pull off the vacuum arrival tube at the solenoid and connect it straight to the turbo, that way you can check whether the turbo works was the idea behind ??
 
Fitted new solenoid with no difference also now refuses to start, leave it for a couple of hours, then fires up. Going into a diesel specialist tomorrow, I'm now suspecting faulty pump.
 
Hi springer1 . Think mine could either be the pump under the wheel arch or the boost solenoid. Finding it hard to start at the moment. Fitter EGR blank and it is better at the low end but sounds like there's no turbo.. If you put it in neutral and rev it, it goes straight up.. Not sure what to try next solenoid or pump..
 
Just sorted out the slow starting problem. Found that there was air getting into the pump causing the Diesel to cavitate. Released the air and it's sorted. Also disconnected the MAF today and went for a drive, load of performance but also loads of black smoke. Connected the MAF back up and it had lost it's performance. Also had a big hose and connected it up to the boost solenoid and found that this is constantly sopping vacuum to the turbo. Not sure if this is right or wrong. Also tested this with the MAF of and it was the same. So I'm not sure at the moment what the fault is. Disconnected the hose to the turbo and it made no difference. What do I try next?
 
Just sorted out the slow starting problem. Found that there was air getting into the pump causing the Diesel to cavitate. Released the air and it's sorted. Also disconnected the MAF today and went for a drive, load of performance but also loads of black smoke. Connected the MAF back up and it had lost it's performance. Also had a big hose and connected it up to the boost solenoid and found that this is constantly sopping vacuum to the turbo. Not sure if this is right or wrong. Also tested this with the MAF of and it was the same. So I'm not sure at the moment what the fault is. Disconnected the hose to the turbo and it made no difference. What do I try next?
 
Had new pump and filter fitted, cured the problem, it flys now. They pressure tested the old pump and plenty of pressure, but very noisy. It must have been sticking.
 
Hi all go easy Im a newby.

I worked on L/R series II/III years ago and well due to the weather over the last couple of years I decided to buy a 4x4. It was only ever going to be a L/R but it had to be family friendly. Now I have had BMW 5 series for some years, so the solution became a no brainer.
I bought an 01 plate SE TD4 3 months ago, 80k on the clock full service history.
Thats the back ground.
When I got it I rang the 'specialists' that had been servicing it to find the back ground. First thing was to change the VCU which had become solid. Since then I have had little time to play with it. Until last W/E. I took put the EGR and de-junked it and as much of the air box as I could, replaced it, job done. NOT.
My good lady took it down the motorway and couldnt get more than 70mph and had a large black cloud following her. On her return I received the mother of all ear bashings. Now BMWs have a habbit of resetting the ECU to any mods or different driving methods- AH maybe it doesnt like having a clean EGR.
I took it out to find it was absolutely gutless. Back at the house I removed the engine cover to find one hose had blown off( intercooler return) and the 90 degree bend out of the EGR was blowing it had become very 'squidgy' over the years from absorbing oil fumes.
I purchased one (dealer part only) £14.50 fitted it and now have full boost.
You cant really tell the hose is leaking unless you rev it above 3k, then you will hear it HISS.
If the vehicle wont go above 70mph you are getting no boast at all, even with a turbo that is not functioning correctly ie failed actuator you will get some boost.
Hope this helps
 
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Have sent the hippo into the garage as it also needed an MOT and mentioned the lack of power to them. They said it was the MAF was faulty and the waste gate was seized open.

Symptom. Using a lot of fuel £20=100miles. Slow to ecellerate and if you put your foot to the floor you get black smoke out of the exaust. Slows down on hills.

Have not had the garage to do the waste gate yet as I needed the car for work but will have a look myself this week and keep you all posted...

Any thoughts most welcome..

Also changed:
MAF
Crank case breather filter
Boost solenoid filter
Turbo vac pipes
Fitted EGR bypass
90 degree intercooler hose
 
Hello all, just thought i'd update you on the cause of my lack of power issues with my Td4 03MY in case it helps anyone.

I initially had a split turbo hose whilst on the M6. It was the short 90 deg hose. Symptoms were initially lack of power, and then black smoke and air whistling sounds. Bought a new one of those for under a tenner and fitted it.

Unfortunately it didn't fix the lack of power over 70mph, but at least there was now no smoke. Symptoms now were that on a slight gradient on the motorway the car would start to lose power and thus speed. There was also a slight noise but not the same as the air noise from the split before.

The Td4 turbo is variable geometry and is controlled by the boost solenoid (see black plastic unit in the picture). It applies a vacuum to the turbo via pipe 1 in the photo. When the vacuum is applied the turbo exhaust side vanes close and it uses more exhaust gas to provide more boost.

My solenoid had failed so that it constantly applied vacuum to the turbo, and thus operated it at max boost all of the time. What then happens is that when you get a high speed / load condition i.e. 70mph and a hill, the ecu senses that the turbo is over boosting and derates the engine by cutting the fuel in order to protect it from damage. It will then speed up again when you get back onto the flat.

The solenoid is STC4198, cost £34, took 15mins to fit (don't need undertray off). Fitted and all working perfectly now.

So if you have lack of power on hills at 70mph, try this test. Pull pipe 1 off the turbo and drive a 70mph hill and see if it cures your issue. If it does, voila it's the boost solenoid. With the pipe off it will be a little sluggish at low speed accels as it won't be able to close the vanes for full boost, but it's fine to drive in order to do your 70mph test.

For info pipe 1 is solenoid vacuum to turbo, pipe 2 is vac supply to solenoid from the plastic reservoir at the side of the engine, pipe 3 is the solenoid vent to fresh air via the little filter. Check these for holes as they rub various engine parts. Also worth checking that your boost solenoid filter isn't blocked, as this would prevent the solenoid from releasing the vacuum and cause the same symptom. Fair chance it's ok though and your solenoid is bust.

Good luck ! :)

also had the won't pass 70mph
put new solenoid valve on my TD4 few days ago and it flys now

Thanks for the tip
 
I have been reading the above posts with great interest especially for those who have had to replace turbo intercooler hoses. For a few quid more why don't you replace with Samco 57mm silicone hoses that are virtually manufactured to last a lifetime.
 
I have been reading the above posts with great interest especially for those who have had to replace turbo intercooler hoses. For a few quid more why don't you replace with Samco 57mm silicone hoses that are virtually manufactured to last a lifetime.

I haven't heard of anyone have silicone hoses fail yet, but please give me a link to the exact product that you are suggesting.

The link 57mm silicone hoses in your post shows only a 1m length of straight hose.

If you were to try fitting that it would kink badly between the intercooler and the ducting.

The turbo hoses need to be formed to shape.

The bigger diameter 90degree bend could be a stock item, but the straight pipe would only work for the little piece after the air temp sensor.

Check on the DPH website and you will see the shape they have to be.

Cheers,

Singvogel.
 
Standard hoses straight off the shelf. No cutting or bending required.
Lengths just right. Bore sizes fit.

Pics below are self explanatory.

LHS.jpg

Upper_RHS.jpg

lower_RHS.jpg

Straight coupling 76mm long X 76mm diameter:
http://www.demon-tweeks.co.uk/Search.do?method=delegate&n=525&p=247850&s=samco

You'll find the rest of what you need over here:
http://www.demon-tweeks.co.uk/samco-universal-elbows

I have been running these hoses in the tropical heat for the past 3 years.......no issues so far.
 
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OK zhoey,

I see what you've done now - several bends joined. ;)

That will work of course - but a lot of extra metal joints and hose-clips.

I don't think it would be much cheaper than the pre-formed hoses from DPH, though.

Caio,

Singvogel. :cool:
 
OK zhoey,

I see what you've done now - several bends joined. ;)

That will work of course - but a lot of extra metal joints and hose-clips.

I don't think it would be much cheaper than the pre-formed hoses from DPH, though.

Caio,

Singvogel. :cool:

Tropical heat here means turbo hoses don't last out anything more than 18 months.
 
Tropical heat here means turbo hoses don't last out anything more than 18 months.

I'm not sure where you are, but I can well imagine the effect of prolonged heat.

I run to the Balkans several times a year and the under-bonnet temperatures are sky high - when you open the bonnet you have to stand back and wait a good few minutes before you can check anything.

Here's a pic of the silicone hoses I have now.

Caio,

Singvogel. :cool:
 

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I'm not sure where you are, but I can well imagine the effect of prolonged heat.

I run to the Balkans several times a year and the under-bonnet temperatures are sky high - when you open the bonnet you have to stand back and wait a good few minutes before you can check anything.

Here's a pic of the silicone hoses I have now.

Caio,

Singvogel. :cool:

Next time we'll all meet some place after a run in our FL's, pop the bonnets, bring out the sausages & chicken wings and have a BBQ. :tea:
 
Next time we'll all meet some place after a run in our FL's, pop the bonnets, bring out the sausages & chicken wings and have a BBQ. :tea:

Hi zhoey,

Thanks for the invitation to the BBQ. :D

You haven't yet said which sun-kissed, coconut-grove bestrewn, tropical paradise island this party will take place. ;);)

Can we have BBQed bananas please? Wrapped in alu-foil on the injector cover?

Caio,

Singvogel. :cool:
 
Hi zhoey,

Thanks for the invitation to the BBQ. :D

You haven't yet said which sun-kissed, coconut-grove bestrewn, tropical paradise island this party will take place. ;);)

Can we have BBQed bananas please? Wrapped in alu-foil on the injector cover?

Caio,

Singvogel. :cool:

Malaysia. No paradise island, yet a little better off than Watford.
 
Thank you Kungfu0210 i will try this and hopefully will fix the problem from what you describe seems to be the exact sympton. than you again all
 
Hi

My 2001 TD4 is still lack of power. I hav changed:

- 2 x fuel pump
- EGR blanking
- vacuum pipes
- Chrankshaft filter
- fuel an air filter
- turbo hoses
- turbo solenoid

But it still lack of power, but no smoke. Engine also rattle to much. But between the engine bay fusebox and the firewall/bulkhead there is an hidden sensor with some red rubber on the top. Its hard to get the finger down there, but it feels like the red colored top is a kind og push-button, and wiring goes in to ECU. Do any of you now what this is?
 
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