MG-Rover.org Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
1,747 Posts
Discussion Starter #1 (Edited)
Hi there I haven't been on the forum for a while due to health etc but now it is time to begin again with all 3 MGS in a state of repair. The one that is puzzling me most is the MGF.
HEAD Gasket blown and cylinder no1 full of water (now repaired with new gasket, water pump, belt etc)

Car was difficult to start but eventually it did but when I tried the 2 X test programmes Mems diags and Rover mems both showed no lambda output so changed lambda, still the same.

Started engine without lambda connected and checked for 12volts to lambda heater from ECU (12v present)
Checked signal pins from Lambda (after engine up to temperature and the Lambda signal is fluctuating between zero and 1v (so appears to be working)

If I connect the lambda it is sometimes difficult to start (but always shown as frozen on the tests)

Has anybody experience of this, is this the ECU, the diagnostics programme or something totally different.

If I wasn't bald I would be ripping my hair out :))))

Thanks in advance
 

·
Rover Lifestyle
Rover 200 Rover 600
Joined
·
12,541 Posts
Are you sure lambda is connected correctly - lambda you changed is proven to be with correct connector and pins are as they should be, or is it generic lambda and you needed to manipulate with connector?
 

·
Registered
Joined
·
1,747 Posts
Discussion Starter #3 (Edited)
No checked out the connector, double checked and treble checked for polarity on the signal and as you see from the signal output of the lambda (checked with hot engine running the o2 sensor output looks correct but connected to the ecu the ecu gives nothing on the diagnostic socket (mems 1.9) and does not appears to be using it)
 

·
Registered
Joined
·
1,747 Posts
Discussion Starter #4
Hi Guys
With respect to my problem it is now solved after blowing up 2 lambda sensors. As you know lambda sensors are very sensitive to over fueling, water, physical damage to the sensor head itself. As the diagnostic units only read what the ECU says my problem would never have been reported.
I decided to drive the MGF to my friends garage which having a dyno has very accurate measuring equipment and as the engine was apparently running ok with the lambda disconnected this distance of a couple of miles would not harm it.
Half a mile from the garage my engine died and would not restart, checked for fuel, seems ok and pump was running, checked for a spark on the coil lead ,ok. Head scratching time….
Double checked everything and now no spark,


The offending HT lead hidden under the inlet manifold had been shorting and eating the carbon inside , eventually destroying itself (and a couple of lambdas due to overfueling. New lead installed (worst job I have ever had to do) and last new Lambda installed checked on the dyno now good emmisions


135486


Cable faults are always the worse especially when access to it is so difficult
 
1 - 4 of 4 Posts
Top