Sickly Griff

[FFMan]

Further to my post yesterday, my girlfriend was driving the griff 500 back from a mates, when the alternator pully disintegrated and lost the fan belt in the process. She pulled imemdiately switched off and the nice man from AA replaced the pulley and belt and off she went.

After approx 40 mins of 70mph on the motorway she says is was hunting on over run when she came to turn off and then missing and lacking power. She pulled up again, and now being closer to home I went out to met her (thank heavens for mobile phones).

Opening the bonnet and checking the electrics revealed no obvious faults, so I drove it back slowly. It is down on power, and feels like its holding back, no obvious pinking but it would be difficult to hear over the engine. Temp and oil pressure is OK

Just before the fan belt gave way she filled up from quarter full with the new v-power (Optimax version 2) fuel - could that be an issue ? Or is it possible that when the belt gave way if damaged the connection to the r/hand lamda sensor (not had a chance to look yet).

What would the ecu do if it couldn't 'see' the lamda sensor ?

Anyone had any experience with v-power fuel ?

Any other ideas ?

[Slacey]

My Griff is run exclusively on V-Power, I've had no issues at all. If the Lambda sensor was damaged you would have a MIL light lit on the dash and a code stored in the ECU - as the engine seems to be down on power this might be the issue as the engine will run badly with a missing / broken Lambda. Check for the MIL light - if it isn't on, it's probably not that and the hunt begins....

[FFMan]

no extra lights on - which is the MIL light then ?

[catretriever]

FYI there was no M.I.L. light for me when my lambda went screwy. The biggest giveaway for me tho' was overfuelling which caused a noticable drop in power, hunting on the overrun, and a stinkier than normal exhaust.

[Slacey]

On the strip of lights to the left of you (the one with the indicator arrows, handbrake & lights symbols etc.)- it literally lights up the letters M.I.L.

A si said, if it's not lit it probably isn't the Lambda that's the problem.

[that daddy]

i had a lambda probe failure that did not put the MIL lamp on, but the car ran like crap on cruise and low RPM,AS YOU WOULD EXPECT WITH LAMBDA PROBE FAILURE.If this turns out to be your problem do both not just one,good luck.

[FFMan]

can one test a lamda with a meter ? They look quite new but I suspect cable damage after the fan belt let go because the cabling to one is right underneath the belt.

[Griffsmith]

Have you tried resetting the ECU first? maybe the ecu detected the power failure when the belt was thrown, and is now running in 'get home mode' which I think ignores the lambdas and just runs rich..

just unplug the ECU for 10 or so seconds then plug it back in a see how it goes... it maybe a little rough for the first 30secs to a minute but should be settle back to normal. worth trying first before you start spending money..

Good luck chris

[FFMan]

thanks for the tips.

i'll try the cpu reset tonight, and examine the wiring to the lamda.

On the mil light issue - does this light up to check the bulb at any point. I have to say i never recall seeing this light.

[FFMan]

on the cpu reset, by disconencting we're just removing the power. i ask because we have a high current race-car type cutout switch on the battery which has no bypass (the clock stops and the radio loses it preset settings).

can i just turn this off for a while ?

is this stuff documented in the Heath bible or for the injection/ignition do i need the correct range rover manual.

[GreenV8S]

Removing the power will reset the ECU i.e. clear the fault codes and remove the adaptive setting.

The only feasible way to test a lambda sensor is to monitor the output voltage with an analogue meter and confirm that it is cycling between rich/lean. If it is cycling then you know the system is basically working. It should be cycling at around 1Hz or faster, if it is slower than this it indicates the lambda sensor is becoming unresponsive and should be replaced. If it isn't cycling at all then the closeed loop lambda control system isn't working, which could be caused by a duff lambda sensor but could be the result of a fault elsewhere.

If you've had a belt fail I'd suggest you look for anything that could have been mechanically damaged or dislodged. Look for anything clean, that's a sign that something has come off recently. It might be a sensor wire, or a vacuum line, or anything that interferes with the ignition of fuel systems, or introduces an air leak.

[FFMan]

good tip - my feeling is that something mechanical has occured and either damaged wiring of introduced an air leak - there is a little breather pipe i recall that is close to the belt.

does anyone know where i might find some good under bonnet pictures so i know what it should look like ?

thanks all, being a new griff owner this breakdown sadly confirmed all those friends and neighbours thoughts on unreliability. sadly the TVR has let her self down this time but will be given an opportunity to make amends in due course.

[FFMan]

had a good look around. i can see a clean patch on the oil filter and a dent, so thats where the pulley pinged off to.

reseated the lambda connectors and gave it all a good inspection - nothing untoward found

reset the cpu by disconnecting the battery for a few mins and took it for a spin. it seems to have recovered ok (as far as i can tell on a dark wet november night). certainly feels ok but we'll see.

thanks for all the help

[shpub]

FFMan said:

is this stuff documented in the Heath bible or for the injection/ignition do i need the correct range rover manual.

Yes it is. There is a whole chapter on testing the various sensors, the ECU fault codes and what they actually mean in reality. Also included are several wiring loom diagrams for the injection system as well.

Also has under bonnet pictures... pictures of various fan belt arrangements and so on.

Edited by shpub on Tuesday 21st November 08:34

[Griffsmith]

FFMan said:

had a good look around. i can see a clean patch on the oil filter and a dent, so thats where the pulley pinged off to.

reseated the lambda connectors and gave it all a good inspection - nothing untoward found

reset the cpu by disconnecting the battery for a few mins and took it for a spin. it seems to have recovered ok (as far as i can tell on a dark wet november night). certainly feels ok but we'll see.

thanks for all the help

I was gonna point you at the Rover EFI fault finding doc, but I think Grifter has already sent a link on another thread. it is also available here www.warks-tvr.org.uk/index.php?option=com_content&task=view&id=24&Itemid=52
there's also plenty of other useful info available in the tech tips, for future reference..

Just remember even if the ECU reset has cleared the fault code and recovered it from 'Safe Mode' then the fault could return.. if it does it indicates that something other than the power failure caused the ECU fault code. then I would lay my hands on a fault code reader to see what that may tell you.. until then I would leave well alone from experience to much poking a prodding can cause more problems..

good luck Chris

[rfisher]

I know you are trying to be helpful Richard but can you refrain from advertising your item every time someone posts about Fault finding . Its against posting rules as it would become very tedious and the threads would become cluttered with everyone advertising this and that.

Thank you

Edited by on Tuesday 21st November 22:03