• Join Premium & Save
      Join Premium & Save
    • Get Your Club gear
      Get Your Club gear
    • Huge Range of Ford Parts
      Huge Range of Ford Parts
    • 1000's Of Fords For Sale
      1000's Of Fords For Sale
    • Share Your Car Experience
      Share Your Car Experience
    • Savings Up to 15% Off For Members
      Savings Up to 15% Off For Members

AdBlock Warning

Parts of this website do not function properly with AdBlock enabled on your device. To get the best user experience on our website, please disable Adblock for this website (domain) on your browser.


Chrisja

Mk7 ford fiesta 1.6 tdci smoke

Recommended Posts

Hello everyone new member here need some help with my car 2011 1.6tdci. 68thousand miles remaped egr not an issue ect. Recently in the last couple weeks had intermitent smoke issue. Sometimes after a mile or a few miles it will start chucking out white greyish smoke cruise light throttle, if i boot it it clears up until i let off, it also smokes bad at idle! If i switch off and restart after a minute it runs clean again. Only seems to do it every now and again. Fuel filter service timing belt fuel system cleaner no change. No fault codes only thing iv noticed is on live data frp when no smoke 25-26 thou kpa when smokeing its up to 40thou kpa at idle. Sorry to jump in straight away thanks for any input. 

Share this post


Link to post
Share on other sites
 

On 23/09/2017 at 9:00 PM, Chrisja said:

Hello everyone new member here need some help with my car 2011 1.6tdci. 68thousand miles remaped egr not an issue ect. Recently in the last couple weeks had intermitent smoke issue. Sometimes after a mile or a few miles it will start chucking out white greyish smoke cruise light throttle, if i boot it it clears up until i let off, it also smokes bad at idle! If i switch off and restart after a minute it runs clean again. Only seems to do it every now and again. Fuel filter service timing belt fuel system cleaner no change. No fault codes only thing iv noticed is on live data frp when no smoke 25-26 thou kpa when smokeing its up to 40thou kpa at idle. Sorry to jump in straight away thanks for any input. 

For anyone that has this issue disconnect mass air flow sensor and drive it i did this and no more smoke but guttless untill 2.5krpm new maff and now she flies all the info says black smoke when maf fails my car only ever chucked white smoke hesitated to 2000 rpm stuttered everynow and again maf was reacting seemingly normal on my obd scanner no faults codes but its a cheap ebay reader bizzar fault that nearly had me coughing up for 4 injectors!

Share this post


Link to post
Share on other sites
On 9/23/2017 at 9:00 PM, Chrisja said:

No fault codes only thing iv noticed is on live data frp when no smoke 25-26 thou kpa when smokeing its up to 40thou kpa at idle.

Has it got a DPF? Could the smoke & raised FRP be connected to a regen? If the DPF is getting a bit full, or there is some fault in the system like perished hoses to the DP sensor, it could be doing the regen more often, and struggling a bit.

The MAF idea above is a good, easy test. Though I can not see how the raised FRP & smoke stacks up. If you over-fuel a diesel, it will just rev up, as there is no throttle as such. (Though, now I think of it, the 1.6TDCI does have a throttle, it is used as part of the EGR system, and as an anti-judder valve at turn off.)

If not that, maybe there is a problem with the frp sensor, or the pressure control valve on the fuel pump. High FRP at idle might make the injectors struggle to deliver the small fuel dose, and that could make it smoke.

 

Share this post


Link to post
Share on other sites
1 hour ago, Tdci-Peter said:

Has it got a DPF? Could the smoke & raised FRP be connected to a regen? If the DPF is getting a bit full, or there is some fault in the system like perished hoses to the DP sensor, it could be doing the regen more often, and struggling a bit.

The MAF idea above is a good, easy test. Though I can not see how the raised FRP & smoke stacks up. If you over-fuel a diesel, it will just rev up, as there is no throttle as such. (Though, now I think of it, the 1.6TDCI does have a throttle, it is used as part of the EGR system, and as an anti-judder valve at turn off.)

If not that, maybe there is a problem with the frp sensor, or the pressure control valve on the fuel pump. High FRP at idle might make the injectors struggle to deliver the small fuel dose, and that could make it smoke.

 

It seems odd maybe the remap haveing that effect with poorly maf?  white smoke is fuel burning too cool. but its driving spot on with no smoke with a new mass air flow sensor dpf is fine sensor reading are in spec for a clean filter and it would smoke after a minute of quiet driving when cold . Every time that old maf got pluged in bang smokeing again. apparently dpf only trys to regen when its at opperating temp and cooling fans kick in dureing a regen but never has. I will see how it goes for a few weeks and report back may just be a coincidence as it was intermitent then all the time but touch wood its sorted. If not i just gonna chuck it to the nearest diesel specialist. Cars are getting too complicated! 

Share this post


Link to post
Share on other sites
12 hours ago, Chrisja said:

It seems odd maybe the remap haveing that effect with poorly maf?  white smoke is fuel burning too cool. but its driving spot on with no smoke with a new mass air flow sensor

I have never been 100% sure what the MAF does on a diesel. It is useful at high power, as the amount of air coming in has to be measured to avoid over-fuelling, with consequent smoke and wasted fuel.

At low power I think it is only used to control the EGR. The EGR flow is not measured directly. The engine air flow can be estimated from RPM & MAP (& IAT). Then the difference between inlet flow (MAF) and engine flow, must be the EGR flow. It is a bit rough, small errors in MAF, MAP, or air path blockage etc, can have quite a big effect on EGR flow.

If the MAF was reading high, then the PCM would raise the EGR flow, possibly by part closing the EGR Throttle valve. The high MAF reading would make it think there was plenty of air (oxygen) going in, but in fact there would not be enough. Thus it would smoke, waste fuel, and have to increase the fuel rate (& FRP) to compensate, in order to maintain RPM.

If an engine has been re-mapped to remove normal EGR operation, this would complicate the situation, it is hard to say in what way.

So hopefully the new MAF will cure the problem.

Share this post


Link to post
Share on other sites

The MAF measures the intake air temp and flow to work out air density (no separate air temp sensor), the MAP alone can only tell you boost pressure.  It helps determine how little fuel you can get away with at idle or cruise to keep the fuel consumption and more importantly emissions low.  As you say, it will also be used with the EGR and air doser so it doesn't lean out too far and caused NOx or melted pistons.

Its actually pretty useless at high rpm because they have a fairly small working range which is why most diesels will put out a bit of smoke near the red line.  Some mappers even map the MAF out if they're going for outright power.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now