Help using diagnostic software

[SteveTusc]

I'm trying to find out the cause of my Tuscan running rich. I've got myself a lead to connect to the ecu and have downloaded the software and user guide. I'm able to connect to the ecu, however I'm sure it's not working properly. The data displayed only stays on screen for a second or two then disappears like the screen is refreshing. I'm assuming this isn't normal? I've tried looking at the data using the 'Real Time' function. However this does the same thing. Am I being a plonker?

Anyway, trying to read what I could before the screen refreshed, I did notice there was an AFR1 fault and the additives on this bank were high. I reset the adaptives and cleared the fault log. I then let the car idle for 30 seconds or so. When I looked again the adaptives were still high on this bank (+23 ish). So I'm happy that’s why it's rich, but what’s causing it? It’s recently been serviced so plugs should be fine, leads are pretty new as well. Other than the coil pack that’s the ignition side ticked. The throttle bodies should have been balanced at the service as well? Does that just leave Lambda sensors or is there something else that can cause an AFR fault?

Any help/advice would be greatly appreciated.

[nrick]

If the diagnostics aren't working

Are you using windows XP/Vista/7 ?
Most faults are caused by the serial to USB convertor, I had to try 3 and use different drivers.

Have you got the latest software from Graham Varleys Site?

On the car if the one bank is running rich then I would suspect the Lambda sensor, could try swapping them, clear the adaptives and see what happens. Could also be wear in the throttle bodies or not set up correctly. Is it decatted? Has it been mapped?

Hope that helps,

N

[SteveTusc]

Thanks Neill I'll swap the lambda sensors over and see what's what. If it is the lambda would you expect a lambda error as well as the afr? The car is de catted and has been mapped, would you expect different readings based on that? The other bank was sat around +1 which is what I was expecting.

I'll try some different drivers on the software also.

Cheers

[PetrolHeadPete]

Once u get the sw running check the lambda on the real time
Should step up and down once the idle has stabilized
Means youre at the balance point of air to fuel
If lambda is flatline then be suspicious of it
Very high adaptive means too much air needing too much fuel
Could be various sources of air leak
Sw first . Then theories can follow

[arjamieson]

Im having a similar (suspect very rich) issue with my T350 2003. 30,000 miles - no issues at all so far.

Generally, it runs like a dream and performance is still as blistering as ever.

However Im now getting only 4 mpg - yes thats 31 miles out of a full tank - on a trackday and about 12-15mpg cruisng on motorway. It used to get about double that.

Any suggestions? Havent managed to connect to ECU yet for diags but had a false starter with the wrong lead - i am awaiting an OBD socket connector since Im pretty sure mine has this instead of the 3 pin which doesnt seem to do anything.

Only signs are sooty exhaust tail pipes (sports exh but not de-cat). And VERY occasional misfire at high rpms / full load.

Only other point to note is that this seemed to coincide with a split fuel tank about 1 year ago - that happened because my breather got blocked and eventually the tank split. That is 100% fixed now and Im certain I am not actually leaking any fuel anywhere.

No visible leaks at all inside the engine, everything is connected up as it should be as far as I can see. After the last service (TVR stansted - absolute rip off by the way) it looks like they may have misseated the air filter just a little - suspect maybe a tiny air leak into the airbox but if so its really nothing major.

help! Im off to the alps in it next weekend for a 2000 mile road trip and at the current rate of fuel consumption its going to be a damned expensive trip!