1.6 tdci engine stutter 18-2200 revs

[n_hudson]

just noticed today climbing a slight hill that when in 3rd and 4th and accelerating slowly, the engine seems to stutter between 1800 and 2200 revs. It’ll climb up to 1800 normally, slow between 1800 and 2200 and then drop back down to 1800 in a stuttering / coughing motion. Once it eventually it gets past 2200 it’s fine. 

I assume it’s not a clutch issue as there’s no smell and the devs drop rather than climb.

The car is now on 64k miles and was serviced at ford 2 weeks ago.

Any ideas?

 

focus mk3 1.6 tdci

[Albert27]

When I had a small hole in my intercooler - manifold pipe, the car would hesitate on slight hill's, almost stutter a little.  Whether it's that or not I don't know but it was around those revs and higher gears.  Check your pipes from the turbo to the intercooler & up to the inlet manifold if you suspect an air leak.   Even then it can be difficult to spot a  split; it was only when i revved the engine and looked i could see the concertina part bulging and exposing the hole!   I also had a hissing sound though and as it got worse the  performance & economy began to be be affected.  Hope that helps anyway.

 

[n_hudson]

Thanks for the reply, I’ll try and strip it down and have a look / listen on Sunday.

Did it hiss when revved at idle? 

[FatHead1979]

1 hour ago, n_hudson said:

Thanks for the reply, I’ll try and strip it down and have a look / listen on Sunday.

Did it hiss when revved at idle? 

My 1.8 TDCi made a definite hissing noise when the intercooler pipe was split, I'd expect all turbo engines to be the same as the principle i.e. boost pressure is the same regardless of the fuel type/manufacturer.

[n_hudson]

7 hours ago, 1979Damian said:

My 1.8 TDCi made a definite hissing noise when the intercooler pipe was split, I'd expect all turbo engines to be the same as the principle i.e. boost pressure is the same regardless of the fuel type/manufacturer.

I’m thinking it’s s boost leak under load, I can’t seem to replicate it at idle or down hill. 

[Albert27]

10 hours ago, n_hudson said:

Thanks for the reply, I’ll try and strip it down and have a look / listen on Sunday.

Did it hiss when revved at idle? 

I'm not sure, it was more noticeable when driving from 2000 rpm when the turbo kicked in.  Would the turbo boost revving at idle?

[Dee_82]

No, idle it has only a tiny positive effect on pressure certainly nothing that would be noticeable. you might hear a small hiss but it wont be much, even if you accelerate in neutral it wont make much of a difference you will only hit about .5 bar of boost... if your lucky, it would be difficult to hear the hiss over the engine.

You have any stored DTCs? boost leak will flag it will also be dumping black smoke out the back. 

whats curious is that once past 2.5k its ok. the boost on this car is controlled by a VTG system. which is actually pretty neat, perhaps, and its just a guess, its sticking, boost increases, VTG sticks, introduces hesitation, once you come off heavy boost (once you reach you RPM) it settle.

Could be fuel related... crank sensor, or underboost due to VGT or leaking hose.  some DTCs would help :)

 

 

[andypsp]

Maybe fuel filter needs replaceing ?

[Dee_82]

maybe, a fuel restriction but again, DTCs would be helpful. The computer will hopefully already know whats wrong, theres no point in guessing if it already can point us in the right direction.

[n_hudson]

5 hours ago, Dee_82 said:

No, idle it has only a tiny positive effect on pressure certainly nothing that would be noticeable. you might hear a small hiss but it wont be much, even if you accelerate in neutral it wont make much of a difference you will only hit about .5 bar of boost... if your lucky, it would be difficult to hear the hiss over the engine.

You have any stored DTCs? boost leak will flag it will also be dumping black smoke out the back. 

whats curious is that once past 2.5k its ok. the boost on this car is controlled by a VTG system. which is actually pretty neat, perhaps, and its just a guess, its sticking, boost increases, VTG sticks, introduces hesitation, once you come off heavy boost (once you reach you RPM) it settle.

Could be fuel related... crank sensor, or underboost due to VGT or leaking hose.  some DTCs would help :)

There are no error codes or warning lights... none, zip, zero... which makes it more annoying

* Sorry messed up with the quote button

 

 

[n_hudson]

32 minutes ago, andypsp said:

Maybe fuel filter needs replaceing ?

Its only just been replaced at Ford during a major service 

[n_hudson]

20 minutes ago, Dee_82 said:

maybe, a fuel restriction but again, DTCs would be helpful. The computer will hopefully already know whats wrong, theres no point in guessing if it already can point us in the right direction.

Codes would be brilliant, but its not kicking up anything, no warning lights... no smoke either... 

[andypsp]

2 hours ago, n_hudson said:

Its only just been replaced at Ford during a major service 

did it have that problem before they changed the filter ?

[n_hudson]

6 minutes ago, andypsp said:

did it have that problem before they changed the filter ?

I noticed it a few times when on the motorway using cruise control, sometimes it would drop off, but I never actually realised that its was it was an issue until now its a constant thing. 

[Tdci-Peter]

22 hours ago, n_hudson said:

climbing a slight hill that when in 3rd and 4th and accelerating slowly, the engine seems to stutter between 1800 and 2200 revs.

This is probably a red herring, as it is a different car and different engine, but have a look at:

The exact problem is not specified by Didder44, except uphill and 2000rpm.

But I do know the glowplugs on the 1.6TDCI can have odd effects, including limp mode. Though usually there is a message or warning light.

But fuel related problems remain more likely, air leaks into the system due to a faulty filter (even though new), damaged pipe connector or damaged fuel pipe are possible. If nothing is obviously wrong, I would hook up a diagnostic system, test thoroughly for codes, and monitor fuel rail pressure, MAP and a few other things on a run, trying to make the fault happen.

Though gremlins usually go into hiding as soon as a meter / scope / computer comes near them!

[n_hudson]

So I stripped out all the pipe work to and from the turbo, intercooler and boost valve hoses this morning... cleaned them up with soapy water and carb cleaner, no "obvious" splits or holes.

Dried them out, put everything back together, gave it a good spray with carb cleaner while its running to see if I'd left anything loose... 

The car seems to have lost the boost issue... But we'll see... 

I have it booked in to Ford, but can't be seen until 10th April and hopefully will save me the £114 diagnostic fee?!!

 

[Albert27]

10 hours ago, n_hudson said:

So I stripped out all the pipe work to and from the turbo, intercooler and boost valve hoses this morning... cleaned them up with soapy water and carb cleaner, no "obvious" splits or holes.

Dried them out, put everything back together, gave it a good spray with carb cleaner while its running to see if I'd left anything loose... 

The car seems to have lost the boost issue... But we'll see... 

I have it booked in to Ford, but can't be seen until 10th April and hopefully will save me the £114 diagnostic fee?!!

 

Have you tried FORScan?  Save you the cost of a diagnostic fee!

[Tdci-Peter]

10 hours ago, n_hudson said:

The car seems to have lost the boost issue... But we'll see...

I hope that is the answer, please keep us posted!

If not, then David has the answer: it is just possible that Forscan or a similar good system could pin down the problem a bit.

A £114 Ford diagnostic readout in a garage will not reveal as much as a Forscan data log run under real life conditions monitoring the engine when the fault actually happens. It will only show historical information (error codes) that can be read equally well by a system like Forscan. The diagnostic capabilities of ford franchised dealers vary enormously from garage to garage.

I, or others here, could provide guidance on how to use it & interpret the results if needed. No guarantees, sometimes the results can be confusing or even misleading, but it is worth a try.

 

[Dee_82]

+1 for forscan

https://tunnelrat-electronics.fwscart.com/USB_Modified_ELM327/p4541936_17045457.aspx

Grab one of those, dont buy any old crap off eBay, you can have problems with those, I got a cheap one which let to an power steering error! This chap above comes highly recommended by users on here.

Get that then download forscan on to a laptop, monitor the MAP MAF, fuel rail pressure VGT % and torque, for reference to where you where when it went wrong id also pull the speed and RPM (its useful to use that to pin point the point of the trip it went wrong. )

failing that you could look in to EGR

 

[n_hudson]

13 hours ago, Dee_82 said:

+1 for forscan

https://tunnelrat-electronics.fwscart.com/USB_Modified_ELM327/p4541936_17045457.aspx

Grab one of those, dont buy any old crap off ebay, you can have problems with those, I got a cheap one which let to an power steering error! This chap above comes highly recommended by users on here.

Get that then download forscan on to a laptop, monitor the MAP MAF, fuel rail pressure VGT % and torque, for reference to where you where when it went wrong id also pull the speed and RPM (its useful to use that to pin point the point of the trip it went wrong. )

failing that you could look in to EGR

 

How do I get hold of Forscan? Is that cheaply and readily available? I had a guy goose my ecu on an old vauxhall with a "genuine" copy of Tech2... I'm always wary these days.

[Tdci-Peter]

2 hours ago, n_hudson said:

How do I get hold of Forscan? Is that cheaply and readily available?

This is my standard bit about Forscan:

Forscan is a powerful Ford specific system, Cost is about £16.00 for the interface. It needs a computer of some sort. (COM port, USB, bluetooth or WiFi interfaces available). You will find a lot about ELM327 & Forscan on this site, which together provide a very comprehensive diagnosis & maintenance tool. James (jeebowhite) has done a nice guide: http://www.fordownersclub.com/forums/applications/core/interface/file/attachment.php?id=21196

The Tunnelrat ELM327s have been reported to work well by several people, and are stated to be compatible with Forscan and ELMConfig.

http://www.spanglefish.com/TunnelratElectronics/index.asp?pageid=516992
or
https://tunnelrat-electronics.fwscart.com/

Forscan works best on a Windows laptop, with a USB ELM.  Forscan is also available for iOS & Android for some tablets & phones, using USB if available, or bluetooth or WiFi ELMs. But there are some limitations.

Wireless ELMs are often not as reliable as the wired ones. Also they are rarer in the "modified" form which is needed to access the 2nd Ford bus system. This 2nd bus is the MS-CAN bus, and links all the car interior electronics like door modules, and the BCM (aka GEM). But a standard ELM will still work with all the Underbonnet Modules (PCM, ABS etc) and with the IC (Instrument Cluster).

The Forscan programme is free (in Windows format) and you can get it from:
http://forscan.org/download.html

-------------

These days you are right to be wary of dodgy software. The Forscan organistion has always been very straightforward and open. It is a voluntary collaboration, avoiding a lot of the commercial pressure that leads to bad software. Just make sure you get it direct from forscan.org, as above. I have never heard adverse reports about this software being malicious.

Never install any software from a CD, unless you are certain the CD is from a very trustable source, and is certified as being the genuine thing.

It is quite powerful, and has facilities to erase all keys, and to re-programme the ECU, for example. But these facilities would require a very deliberate attempt to use, and it always warns before doing a non-reversible operation, allowing you to exit. Just read the screen before clicking ok or continue!

Loads of people on this site have used it, most not being techno geeks or computer wizards, without damaging their car, and often to great benefit.

 

 

 

[Dee_82]

Just to add to Peters piece above, the chap that Peter and I have linked to DOES sell a bluetooth switchable ELM327 device and it works flawlessly. The only problem with bluetooth is that it introduces a small delay between what happens and what is recoreded. for the vast majority of cases this isn't a problem and is in fact a necessity if using android devices but if your trying to monitor very small spikes then it might miss them....thankfully that chap also has that covered as well with a switchable bluetooth AND USB device :D 

for the record he has nothing to do with me but ive brought several of his devices over the years and absolutely none of them have let me down, which I cant say is true of the crap wifi, BT and USB ones I got from eBay. incidentally, I did speak to him once regarding a small question about BT, this was before he released his switchable BT model and found him very helpful

 

[n_hudson]

So, after thinking it had been fixed, the issue popped up again...  2 weeks of nothing and cancelling the diagnosis appointment... brilliant.

I'm beginning to think its a fuel issue, the rev range 1800-2200 surely can't be the peak boost and theres still no noises...

[Tdci-Peter]

3 hours ago, n_hudson said:

the rev range 1800-2200 surely can't be the peak boost

The engine hits maximum torque at about 1700 - 1800rpm. So the turbo is likely to already be fully up to speed and pressure by then. Torque then remains almost flat, dropping slightly, until max power at about 3800rpm.

So it is hard to eliminate either fuel or air systems by the symptoms alone.

I can not see what sort of actuator the turbo has on your car. If it is vacuum, with a solenoid, then that sort of cycling is one symptom of a bad solenoid. The DV6C diagram shows a turbo position sensor, and a "TGV actuator", whatever that is,

[Dee_82]

because our turbo has a variable vane system built in, peak boost could be at almost any point irrespective of RPM.  The VGT has a vacuum controlled solenoid controlling the vanes and a sensor relating to a PID which forscan will pick up on, its measured in % 

Peak Torque and power whilst reliant on the boost pressure, they aren't tied to one another because of the vanes ability to open and close, increasing /  decreasing boost, its a much faster way to achieve good torque at low RPM and keep that torque curve growing until it hits the wall when fuel flow becomes the limiting factor. That's why you can drop in some BMW injectors and hit 200BHP :D but we couldn't hope for more than 140 as it is.

If your fuel pressure or boost is too low or too high you will get a DTC. there is literally dozens of possible things that could cause it, id seriously consider getting the ELM adaptor we talked about before and start to investigate this yourself, if you take it to a garage and they start fishing for the problem it could cost you 100s.