New MAF, but no improvement

Austin Rover · 29th October 2010, 00:15

A new addition to the household is a '03 MG ZTT CDTi with 95,000 miles. It was a bit lethargic at low revs and behaved similar to my diesel 75 before it had a new MAF sensor.

A new MAF for the MG was bought from eBay (but not the same seller as the one for my 75) and it was fitted, but if anything the car is now worse and is absolutely sluggish under 2,000rpm. The 75 will pull away from 30mph in 4th easily, but the MG doesn't want to know!

Is there anything else I should be doing/should have done?

Greeners · 29th October 2010, 00:48

Unplug the MAF and see if there is any difference, you may have a faulty one.

pablo892 · 29th October 2010, 08:20

Also, please could you post a link to the seller you bought it off - could be a chinese copy?

P

wuzerk · 29th October 2010, 10:58

If the performance is worse with the new Maf than it was with the Maf unplugged then it is not working properly. The cheap reproduction ones on E bay look very good but whether they work is another thing.

rossocorsa · 29th October 2010, 22:44

in addition to maf issues do a full service, clean the EGR valve (actually if it's really mucky it could be stuck partially open) or ideally replace it with a bypass, replace the pcv valve all these make a difference which cumulatively can make a big difference. Additionally you could do the air intake mod ( I suspect 99% placebo effect) and once all is well add a ron box

Austin Rover · 1st November 2010, 16:11

Thanks for the replies. I swapped the two sensors between the ZT and my 75, and the poor performance moved to the other car with the sensor. It'll be going back to the eBay trader as it is obviously at fault.

Greeners · 1st November 2010, 16:15

Quote:

Originally Posted by Austin Rover

Thanks for the replies. I swapped the two sensors between the ZT and my 75, and the poor performance moved to the other car with the sensor. It'll be going back to the eBay trader as it is obviously at fault.

Get a refund and buy a genuine Bosch one, pricey I know but they are very reliable.

chris36 · 1st November 2010, 20:20

I chased round a MAF fault on mine, ended up buying a Pierburg with Mafam...........it was sa bit better. Anyway to cut a long story short - It was the Intercooler seals, Easiest & cheapest job ever done. Well worth investigating. Mine were actually sitting in the intercooler.

29th October 2010, 00:15	#1
Austin Rover Newbie Rover 75 Club CDT Join Date: Sep 2009 Location: Huddersfield, West Yorkshire Posts: 27 Thanks: 0 Thanked 0 Times in 0 Posts	New MAF, but no improvement A new addition to the household is a '03 MG ZTT CDTi with 95,000 miles. It was a bit lethargic at low revs and behaved similar to my diesel 75 before it had a new MAF sensor. A new MAF for the MG was bought from eBay (but not the same seller as the one for my 75) and it was fitted, but if anything the car is now worse and is absolutely sluggish under 2,000rpm. The 75 will pull away from 30mph in 4th easily, but the MG doesn't want to know! Is there anything else I should be doing/should have done? __________________ Rich Gelder 2003 Rover 75 Club CDT 1986 Austin Montego 1.6 HL 1984 Austin Maestro 1.3 HL

29th October 2010, 00:48	#2
Greeners Moderator MG-ZTT Join Date: Mar 2007 Location: Ware, Herts Posts: 19,798 Thanks: 161 Thanked 1,249 Times in 1,036 Posts	Unplug the MAF and see if there is any difference, you may have a faulty one. __________________ *David* Impecunity is the mother of ingenuity Useful how to's for common problems Car Of The Month Jan 2014 [SatNav Power Down] [Coolant Level] [SatNav Repair] [Diesel Non Starting] [Paint Codes] [Rear Light Seals] [Reversing Light Switch] [Bleeding Brakes][Sunroof Drain] [Early ZT's][Instrument Pack Diagnostics][ATC Diagnostics]

29th October 2010, 10:58	#4
wuzerk Passed Away Rover 75 CDT 03 auto Conn. SE Join Date: May 2009 Location: London Posts: 2,885 Thanks: 104 Thanked 254 Times in 204 Posts	Maf If the performance is worse with the new Maf than it was with the Maf unplugged then it is not working properly. The cheap reproduction ones on E bay look very good but whether they work is another thing. Last edited by wuzerk; 29th October 2010 at 20:00..

1st November 2010, 16:11	#6
Austin Rover Newbie Rover 75 Club CDT Join Date: Sep 2009 Location: Huddersfield, West Yorkshire Posts: 27 Thanks: 0 Thanked 0 Times in 0 Posts	Thanks for the replies. I swapped the two sensors between the ZT and my 75, and the poor performance moved to the other car with the sensor. It'll be going back to the eBay trader as it is obviously at fault. __________________ Rich Gelder 2003 Rover 75 Club CDT 1986 Austin Montego 1.6 HL 1984 Austin Maestro 1.3 HL

29th October 2010, 08:20	#3
pablo892 Newbie MG ZT 135+ Join Date: Sep 2010 Location: Preston Posts: 27 Thanks: 0 Thanked 0 Times in 0 Posts	Also, please could you post a link to the seller you bought it off - could be a chinese copy? P

29th October 2010, 22:44	#5
rossocorsa Posted a thing or two None Join Date: Feb 2010 Location: GRIMSBY Posts: 1,243 Thanks: 0 Thanked 1 Time in 1 Post	in addition to maf issues do a full service, clean the EGR valve (actually if it's really mucky it could be stuck partially open) or ideally replace it with a bypass, replace the pcv valve all these make a difference which cumulatively can make a big difference. Additionally you could do the air intake mod ( I suspect 99% placebo effect) and once all is well add a ron box

1st November 2010, 20:20	#8
chris36 Regular poster ROVER 75 CDT Join Date: Jul 2010 Location: Sussex Posts: 35 Thanks: 0 Thanked 0 Times in 0 Posts	I chased round a MAF fault on mine, ended up buying a Pierburg with Mafam...........it was sa bit better. Anyway to cut a long story short - It was the Intercooler seals, Easiest & cheapest job ever done. Well worth investigating. Mine were actually sitting in the intercooler.