Running rough - power issues

[mools]

Hey all,

My '06 Td5 defender (and me) are having a few power related issues.

From steady revs cruising on the highway if I put my foot down, to overtake for instance, I'm not getting the fast response I used to get. Increasingly frequently the engine seems to choke, I get no power, like the engine tries to respond but gets over ridden - engine chugging and feeling a bit rough. I then have to drop off the power to get a smooth feel back and pull back in behind the vehicle in front with the feeling of embarrassment which accompanies a failed over taking attempt. Strangely though if I feed power on very slowly this doesn't seem to happen, it just takes too long. It never used to do this, the vehicle has bags of power; chipped, intercooler, exhaust etc. so somethings up.

My first thought was that the exhaust center box had collapsed - as I'd noticed more soot and fiberglass filaments at the tail pipe - but I had this chopped out and still the problem persists, although lower down power and exhaust note are now better. So I'm wondering what's the cause; faulty EGR valve is my next theory?

Any one here had similar symptoms with a Td5? If so what caused them and how did you solve them? How can I test weather it's the EGR? If I unplug the MAF meter will this prevent the EGR working when it uses the default MAF values? This might help me work out if it is the EGR valve.

I'm planning on blanking off the EGR but I really want to get to the bottom of this before I make any changes.

I'd Really appreciate some opinions / advice on this - it's bugging the hell out of me and making me (and defenders) look daft - too many failed overtakes! I want my old beast back!

Thanks a lot,

mools.

[justinc]

Mools, sounds quite like either a delaminated intercooler hose, or the beginnings of a fuel pump failure. Remove the hoses and pipework from the turbo to the intercooler on the passenger side of the engine bay and have a look inside for signs of delamination. The later hoses were of better quality so it isn't as common, but worth checking all the same.


JC

[Allan]

Check the cat. I seem to remember someone on here a few months ago had this type of problem and it was traced to the cat. Worth a try.

Allan

[jakeslouw]

I second the delaminated turbo hose theory.

[Tombie]

Mools, sounds quite like either a delaminated intercooler hose, or the beginnings of a fuel pump failure. Remove the hoses and pipework from the turbo to the intercooler on the passenger side of the engine bay and have a look inside for signs of delamination. The later hoses were of better quality so it isn't as common, but worth checking all the same.


JC

Laggy response, bit more soot...

Justins suggestions +...

Disconnect MAF at plug and go for drive, if it feels the same.... ;)

EGR jammed open will cause it too.

[mools]

Ok guys,

Thanks for the responses - got some stuff to go on there.

I had noticed that one of the intercooler hoses (the short one towards the bottom) was softer than the others, so I already have some silicone hoses en-route from the UK. I'll just take it easy until then, don't want bits of hose flying up the turbo!

I'll try disconnecting the MAF tomorrow and see what the go is. On recollection, I never had this issue before I put in a new MAF - soon after I noticed more soot.

Am I right in thinking that if the MAF isn't working then the EGR valve won't actuate? So IF it is stuck open I'd have to free it up manually?

As a slight aside when I blank of the EGR I'm also going to fit an EMS2 system - if anyone here has tapped the exhaust manifold to place an EGT sensor any tips would be greatly received - nervous about messing it up.

Thanks for your help so far, I'll let you know how it goes.

Thanks,

Mools.

[Rimmer]

Tapping into the exhaust manifold is pretty staight forward.

I think Tombie gave me this advice a while back when I did mine!

Remove the manifold from the vehicle, this prevents swarf finding it's way into the turbo later.

While you have the manifold off. Either remove completely or cut a slot in the webbing between outlets/ports. Also drill out the end stud holes.

From memory this is better explained with pics on Tombies website (TRT).

Good luck,

Tod.

[Mellow Yellow]

I've fitted an EMS-2 along with the EGT probe.

The easiest and IMO as good a place as any to fit the EGT probe is where the EGR system takes exhaust gasses for recirculation.

Contact The Entertainer (on this forum) as he provides EGR removal kits with the option of a drilled exhaust manifold plate to take an EGT probe.

Also, check out a post by Bush65 on fitting the probe. http://www.aulro.com/afvb/technical-chatter/85563-low-egt-temps-2.html (http://www.aulro.com/afvb/technical-chatter/85563-low-egt-temps-2.html)

You'll also find a very good set of instructions at this site Alive Tuning - Real Land Rover Performance for TDi, TD4, TD5, TD6, TDV6, TDV8, Puma (http://www.td5alive.com/egr.php)

[mools]

Well, disconnecting the MAF thankfully solved the power problem - I think I'll keep it like that until I've done the EGR removal. :)

Regarding the Manifold and not wanting to sound like a smart arse; I've read around this a bit and I want to tap the manifold to get a meaningful reading of EGT. Having read posts by others and looked at the engine I don't think you can get one at the blanking plate location on a Td5 - or at least not without quite a long probe. So thanks for your suggestion MY but I will be courageous on this one and drill a hole (maybe). That said if you have any tips on any other points regarding installing the EMS2 I'd really appreciate them.

Rimmer / Tombie - had a gander at the TRT site - removing / slotting the webbing on the manifold sounds like a sensible idea but has there been any issues with this weakening it? How best to cut it away? I've never dealt with cast Iron (can you even drill it with a high speed bit?) I only have access to pretty crap tools so I guess I would probably need to pay for someone to machine it out properly (and tap the sensor hole at the same time). Any advice gladly received. Don't think I have the stomach for a ceramic coating - bit a nice idea.

Anyway - enough with the questions - I'm off out to do some overtaking :cool:

[slug_burner]

you can drill cast iron with ordinary everyday drill bits. Like any drilling do not let the drill bit or the work get hot as you will alter the properties and lose the hardness of the drill bit and possibly harden the cast iron. If you don't know about keeping your cutting tools from getting hot you might be better off having someone else do it for you.

I would use low speed and a bit of pressure, coolant if you have it.

[Mellow Yellow]

Regarding the Manifold and not wanting to sound like a smart arse; I've read around this a bit and I want to tap the manifold to get a meaningful reading of EGT. Having read posts by others and looked at the engine I don't think you can get one at the blanking plate location on a Td5 - or at least not without quite a long probe. So thanks for your suggestion MY but I will be courageous on this one and drill a hole (maybe). That said if you have any tips on any other points regarding installing the EMS2 I'd really appreciate them.

:cool:

So I take it you'd already seen the two links I sent you. Fair enough, you're obviously a very thorough bloke when it comes to scouring the forum.

On the location of the probe, not that it matters if you're going to take the manifold off, I guess you've also seen Discowhite's posts on locating an EGT probe.

[mools]

I take knowledge where (and when) I can find it and seek advice when I need it. At the moment I'm theory rich but experience poor; trying to plug a few gaps before I get on the practical and potentially costly learning curve of this job.

Collective knowledge and the willingness of individuals to contribute to it is what makes this forum (and Land Rover ownership) so great. Funnily enough it's also what separates humans from the majority of other animals.

A little philosophical for a power related thread perhaps, but my way of saying thanks to those who contribute.

Cheers all.

(a morning off work seems good for the soul :D)

[Naks]

From steady revs cruising on the highway if I put my foot down, to overtake for instance, I'm not getting the fast response I used to get. Increasingly frequently the engine seems to choke, I get no power, like the engine tries to respond but gets over ridden - engine chugging and feeling a bit rough. I then have to drop off the power to get a smooth feel back and pull back in behind the vehicle in front with the feeling of embarrassment which accompanies a failed over taking attempt. Strangely though if I feed power on very slowly this doesn't seem to happen, it just takes too long.


Mools, be sure to check your fuel pump and filter as well. It could be that the pump is not performing 100%! So when you accelerate slowly, it can cope, but as soon as you put foot, it cannot keep up and staves the engine of, leading to the chugging/choking.

[mools]

Naks,

I reckon I've got to the bottom of it - well side-steped the issue until I do the EGR blanking job. Appears to have been an EGR valve issue - no valve = no issue ;).

The fuel filter is 2k old and the fuel pump just makes it's usual noise. But I want to ask - how can you check the fuel pump? I'm sure that there'll come a time when I'll want to know this. I know where it is, how to get to it (don't really want the drama though - I have slide draws bolted in the back, a tow bar and second tank.... big hassle to cut through or drop the tank) but how would you check it's condition?

I've only found one post referring to actually checking the fuel pump http://www.aulro.com/afvb/90-110-130-defender-county/78989-td5-def-fuel-pump-noise-loss-power.html

Which suggests "plug a pressure gauge in (back of engine, in front of bulkhead, steering wheel side). Go for a drive it should maintain 4 bar at tickover and right through the rev range."

But I'm not sure what this coupling is and how one would go about attaching a gauge to it, Do you know? Or do you have a different way of checking the pump?

Thanks,

Mools

[Naks]

Do you know? Or do you have a different way of checking the pump?

Yep, I send the landy to the independent mechanic :angel: