DTC Codes help

[ajzetecs]

over past few days been getting engine malfunction warning. My car has lost a lot of power especially pulling away, its quite embarrasing, just dies then with my foot right down no power then all of a sudden full power.

Came home today and engine light which is a first, and these msgs below from forscan.

Any ideas, think i may need to replace mass airflow or clean in, took plug of and contacts were perfectly clean.

[ajzetecs]

apologize for pics 

[isetta]

i recall some years ago my brother's audi tt had the symptom you describe and it was a faulty maf sensor.

did you try driving it without maf sensor connected? was it just the same.

i know on some cars if you disconnect the maf sensor the car uses preprogrammed readings , a kind of average so it can still drive not too badly. so i am wondering if you find it drives better with no maf sensor connected than with it connected which would suggest it is a faulty maf sensor

[ajzetecs]

8 hours ago, isetta said:

i recall some years ago my brother's audi tt had the symptom you describe and it was a faulty maf sensor.

did you try driving it without maf sensor connected? was it just the same.

i know on some cars if you disconnect the maf sensor the car uses preprogrammed readings , a kind of average so it can still drive not too badly. so i am wondering if you find it drives better with no maf sensor connected than with it connected which would suggest it is a faulty maf sensor

Cheers will try that mate, kind of been put on hold today with birth if child but hope it will work.

[ajzetecs]

Fogot to mention noticed second injector was damp and the botton of black pipe to left of injrctor has fuel on it.

[Tdci-Peter]

On 26/01/2017 at 7:53 PM, ajzetecs said:

Came home today and engine light which is a first, and these msgs below from forscan.

P010F - Mass or volume air flow sensor A/B correlation.

That is a bit of an odd error. I have seen A/B correlation related to throttles & accelerator pedals, which have dual redundant sensors that are compared to each other. But the MAF itself has only a single flow sensor & output.

I suspect it may be a comparison between the airflow from the MAF, and an airflow calculated from rpm, the MAP (inlet pressure) and the IAT (inlet temperature). There are quite a few potential causes of a mismatch here:

MAF, MAP, IAT, EGR valve.

The EGR reduces the MAF flow compared to the actual engine air flow, as it recirculates exhaust gas.

Isetta's advice is good, to unplug the MAF. This should cause an error (DTC), but if the car drives better without it, then MAF is at fault. If no better, then maybe it is one of the other elements above. A leaking or stuck part open EGR could do it.

The injector leak sounds like a leak off pipe connection leaking. If so, it needs attention, but is not relevant (as far as I can see!) to this problem.

[ajzetecs]

8 hours ago, Tdci-Peter said:

P010F - Mass or volume air flow sensor A/B correlation.

That is a bit of an odd error. I have seen A/B correlation related to throttles & accelerator pedals, which have dual redundant sensors that are compared to each other. But the MAF itself has only a single flow sensor & output.

I suspect it may be a comparison between the airflow from the MAF, and an airflow calculated from rpm, the MAP (inlet pressure) and the IAT (inlet temperature). There are quite a few potential causes of a mismatch here:

MAF, MAP, IAT, EGR valve.

The EGR reduces the MAF flow compared to the actual engine air flow, as it recirculates exhaust gas.

Isetta's advice is good, to unplug the MAF. This should cause an error (DTC), but if the car drives better without it, then MAF is at fault. If no better, then maybe it is one of the other elements above. A leaking or stuck part open EGR could do it.

The injector leak sounds like a leak off pipe connection leaking. If so, it needs attention, but is not relevant (as far as I can see!) to this problem.

cheers peter, gona try disconnecting maf when get time just tied up at the minute, using partners qashqai much better on fuel and dont trust mine at minute till pind issue. On the egr i had mine delete via remap.  

[ajzetecs]

Update on my issues.

Disconnected maf plug and car is running great, great is an understatement, the power increase is off the scale, nothing like before, hope ecu is not making this happen as temporary

[Tdci-Peter]

37 minutes ago, ajzetecs said:

Disconnected maf plug and car is running great, great is an understatement, the power increase is off the scale, nothing like before,

That sounds like really good news. When a 1.8TDCI is running just right, it does pull very nicely indeed.

I guess the EML is (or perhaps shortly will) come on with a MAF error code. That should not alter the running of the engine though.

The MAF should give a more accurate measurement of the airflow than the MAP, IAT & rpm method. It may be that the fuel consumption increases without it, or there is excess smoke at full throttle. If so, it may be advisable to get a replacement MAF.

Please let us know how it goes, and what DTCs if any, are being generated.

[ajzetecs]

23 hours ago, Tdci-Peter said:

That sounds like really good news. When a 1.8TDCI is running just right, it does pull very nicely indeed.

I guess the EML is (or perhaps shortly will) come on with a MAF error code. That should not alter the running of the engine though.

The MAF should give a more accurate measurement of the airflow than the MAP, IAT & rpm method. It may be that the fuel consumption increases without it, or there is excess smoke at full throttle. If so, it may be advisable to get a replacement MAF.

Please let us know how it goes, and what DTCs if any, are being generated.

Very pleased because i assume the worst, too be honest my car has never driven so well, can actually stay in 2nd at crawl speed and it doesn't surge forward wanting to stall, that was one of my pet hates and the jerking has stopped.

Have not checked DTC codes although the engine light is present which is normal.

I have purchased a full replacement box, maf and pipe for £35, i tried the drilled airbox mod which maybe as done no good no maf so back to basics.

[Tdci-Peter]

17 minutes ago, ajzetecs said:

my car has never driven so well, can actually stay in 2nd at crawl speed

My 1.8 will pull smoothly and quite strongly at idle revs, I can drive along bumpy and hilly tracks at tickover with a heavy load, and it keeps spot on to the 850 - 900 rpm regardless, with no feet on any pedal, in 2nd or 3rd gear. After many years driving petrol carburetor cars, it is a bit weird, almost alarming, to feel that almost unstoppable driving force.

There is a slightly weak area from idle rpm to about 1700 rpm, where you have to feed in the power gently, then you can open up, and it will pull away with massive force.

Please let us know how the replacement MAF goes. Hopefully that is the underlying problem. Unfortunately, there is no certainty in these things until you try it!

[ajzetecs]

will let you know if works ok hope one i have bought is ok with airbox, will remove sensor and give clean before install

[ajzetecs]

On 29/01/2017 at 10:04 PM, Tdci-Peter said:

My 1.8 will pull smoothly and quite strongly at idle revs, I can drive along bumpy and hilly tracks at tickover with a heavy load, and it keeps spot on to the 850 - 900 rpm regardless, with no feet on any pedal, in 2nd or 3rd gear. After many years driving petrol carburetor cars, it is a bit weird, almost alarming, to feel that almost unstoppable driving force.

There is a slightly weak area from idle rpm to about 1700 rpm, where you have to feed in the power gently, then you can open up, and it will pull away with massive force.

Please let us know how the replacement MAF goes. Hopefully that is the underlying problem. Unfortunately, there is no certainty in these things until you try it!

Change whole airbox(un-drilled) new pipe with maf which i removed and cleaned, cleared dtc codes and is running even quicker than with senor plug removed, just shows has been causing issues for a while because never had this power.