R

rich25

New Member
Hi all, I am having an issue with my td4 auto 2003. A few weeks ago it started idling rough revs jumping up and down and occasionally even stalling. so far i have replaced crankcase breather filter and depression limiter valve although i do this regularly anyway thanks to previous advise from you guys. I have also removed and cleaned egr valve and intake manifold a lot of gunk in there. I have run some injector cleaner through and also had high pressure fuel pump changed about 2 months ago due to another issue. The problem still continues and has stalled about 6 times today but always when idling at traffic lights and such. when it is above 1000 revs it runs very smooth and i am desperate to get this issue sorted as it is spoiling an otherwise very well running car very frustrating:(. Any advise would be greatly appreciated thanks in advance.

Rich.
 
Try cleaning the contacts of the fuel rail pressure sensor connection...

try it with the maf disconnected....
 
thank you for reply i will try these things are they costly to replace if faulty and what should happen with maf disconnected? thanks

Rich.
 
just disconnected the maf sensor and ran the engine obviously diagnostics light stayed on but engine idling a lot smoother when reconnected still smoother could this just be a fluke or could disconnecting the maf have cleared any gunk on the connectors i am gonna get the covers back on and take it for a run to see if the problem returns
 
Hi could be faulty MAF sensor my td4 had a stall problam i thought it was me ! i have since replaced the MAF and it does not stall as it did !
 
seems to be running better hopefully not just a fluke i will take the sensor off and give it a good clean on the weekend not much time today thank you for the advice i think you have definitely put me on the right track.Thanks again.

Rich.
 
hi ian jones thank you for the reply if cleaning the maf sensor does not work how much was your maf sensor. I am sure you can appreciate how frustrated this problem is making me if your freelander has done the same.

Rich.
 
rich25 said:
hi ian jones thank you for the reply if cleaning the maf sensor does not work how much was your maf sensor. I am sure you can appreciate how frustrated this problem is making me if your freelander has done the same.

Rich.
Click to expand...
Hi Rich,
look on Rover Rons site sorry i can't find the link all the info you require about maf sensors is on there :)
 
rich25 said:
just disconnected the maf sensor and ran the engine obviously diagnostics light stayed on but engine idling a lot smoother when reconnected still smoother could this just be a fluke or could disconnecting the maf have cleared any gunk on the connectors i am gonna get the covers back on and take it for a run to see if the problem returns
Click to expand...

The MIL will stay on while maf disconnected on an auto, nothing to worry about. I must say i didn't think of a dirty maf connection but if it has cleared the fault all well and good. Did you also clean the fuel pressure sensor connection at the same time? That connection is a common enough cause of poor running and if you did clean it that's more likely to explain why it now runs better.
 
thank you for replies i didnt touch the fuel sensor and went straight to the maf didnt have enough time to take off totally and clean but i disconnected it to see how it ran and was much smoother when i plugged it back in it stayed smooth and all been well again today no stalling or rough idle i will still take it off on the weekend and give it a clean but all seems ok very strange. could this have been some corrosion on the terminals and taking connector off and on again has made a stronger connection or could have reset ecu in some way? dont know much at all about the ecu is this even possible? thanks again.
 
rich25 said:
thank you for replies i didnt touch the fuel sensor and went straight to the maf didnt have enough time to take off totally and clean but i disconnected it to see how it ran and was much smoother when i plugged it back in it stayed smooth and all been well again today no stalling or rough idle i will still take it off on the weekend and give it a clean but all seems ok very strange. could this have been some corrosion on the terminals and taking connector off and on again has made a stronger connection or could have reset ecu in some way? dont know much at all about the ecu is this even possible? thanks again.
Click to expand...


Disconnecting the maf forces the ecu to use default values for airflow based on other sensor inputs like rpm, throttle position etc.
Usually if the engine runs better like this it's a fairly reliable indication that the maf is shot. However in your case it does seem likely that there is/was a bad connection if that is the only thing you have touched. Now that it's reconnected and running OK and there is no Mil on it's now reverted back to using the maf signal.
If it were a manual the only way to confirm a maf signal is via live data as disconnection doesn't light the Mil.
 
Thank you very much for information chaser it seems to be running fine still so thanks to you and everyone that has replied:):):):)
 
I hope I'm not intruding, since the issue in this thread has been resolved. On a related note, I'm reading here that some are saying they've disconnected their MAF sensor, and the vehicle runs well. I've been noticing some bad smell (too rich fuel mixture), extremely slow warm up in the morning and overall bad running. I'm trying to narrow down what could be the causes. I disconnected my MAF and the engine immediately stopped running altogether. Does anyone know what this means for me?

Thank you in advance?
 
2002 freebie se said:
I hope I'm not intruding, since the issue in this thread has been resolved. On a related note, I'm reading here that some are saying they've disconnected their MAF sensor, and the vehicle runs well. I've been noticing some bad smell (too rich fuel mixture), extremely slow warm up in the morning and overall bad running. I'm trying to narrow down what could be the causes. I disconnected my MAF and the engine immediately stopped running altogether. Does anyone know what this means for me?

Thank you in advance?
Click to expand...

TD4 or petrol?
 
Sorry, I should have mentioned. Its a petrol (American) version, 2.5 V6, automatic. I changed the spark plugs and both front and rear oxygen sensors, and the problem persists.
 
2002 freebie se said:
Sorry, I should have mentioned. Its a petrol (American) version, 2.5 V6, automatic. I changed the spark plugs and both front and rear oxygen sensors, and the problem persists.
Click to expand...

TD4 will run without MAF connected as ECU reverts to standard settings. A petrol one won't run without MAF connected.
 
The Mad Hat Man said:
poor sod :rolleyes:
Click to expand...

LOL! Thanks for the pity. I've gotta say, my experience hasn't been half bad considering what I've read and heard about these vehicles. I bought it brand new in 2002 and it currently has almost 130,000 miles on the clock. It usually drives very, very well.

The interesting thing is that, throughout all this rough running I'm still maintaining very good gas mileage. I generally get between 340 - 360 miles out of a 15.9 gallon tankful, and I just got 346.

Thanks in advance for any and all suggestions.
:)
 
markwizard said:
TD4 will run without MAF connected as ECU reverts to standard settings. A petrol one won't run without MAF connected.
Click to expand...

Ok, thanks. Then the vehicle is responding to the disconnect as it should. Guess I'll just keep trying.

Can you think of any suggestions as to the rough idling/running/slow warm up? As mentioned, I already tried replacing spark plugs and both oxygen sensors.
 
You must log in or register to reply here.

Similar threads

T
Rough Idle (holding on breaks)
Replies
1
Views
260
BIGrabbit100
B
D
Stutter and stalling when under load P0336
Replies
4
Views
433
Defender or wife
D
O
Front passenger door on Freelander 2 won’t open
Replies
2
Views
682
Arctic2
Arctic2
r8hilbocus
300tdi auto (EDC) revs hunting and surging - idling+ driving
Replies
2
Views
640
r8hilbocus
r8hilbocus
r8hilbocus
300tdi auto (EDC) revs hunting and surging - idling+ driving
Replies
0
Views
542
r8hilbocus
r8hilbocus