Gems running narrow Lambda on Subaru99 ?

[RobEvo5]

Hi just bought a subaru that has a gems fitted, and was just wondering if it uses the standard narrow band lambda to partly control fuel on idle etc. i.e use the narrow band lambda the same as an OEM Ecu would.

Reason I ask is having borrowed my friends wideband my car would appear to be running rich on idle at about 12.5 afr with slight hunting as a result. My Narrow band Lamda could be shot, and about to get another put in, but won't bother if the gems doesn't run the lambda. ?

Its was fitted in 2008 and the number on the connector is Subaru 99/20611

Also whilst writing is the Anti lag something you have to enable in the software as well as picking up on relevant pins and putting a switch in ?.

Also is Cold start an its ability to hold rpm and idle until the engine is a bit warm common on this model/year. Or something that is posible to map out ?. At the moment I find I have to start the car, hold revs at about 1500rpm for about 30secs or more until it will hold idle.

Many thanks in advance.
Rob

[RickS]

Hi Rob,
Idle values are set internally by the use of options and tables.
Q1.There are three conditions for idle speed control;
1 Engine_speed < Idle_speed and Throttle < max_Idle_TPS, then the Idle cool and Idle speed tables are active.
2 Engine_speed > Idle_speed or Throttle > max_Idle_TPS and PBW is off, then Idle_High is active. (PBW=Pop, Bang, Whiz or ALS)
3 Engine_speed > Idle_speed or Throttle > max_Idle_TPS and PBW is on, then Idle_PBW is active.

Q2. ALS/PBW is software enabled when certain conditions are met and once a manual switch is thrown.

Q3.The Hi idle mode is activated for an amount of time, Set by the option Hi Idle Time, after start up. This should be able to sort your Cold Start problem.

When you bought the vehicle, did you receive any calibration software and licence dongle, as you will need these to action any mapping. Alternately, find a tuner that is well versed with GEMS tuning. Check out the 'Resellers' section of our website and they should be able to point you in the right direction.

HTH
RickS

[RickS]

......... forgot to mention, the manual for this ECU is available for download from the GEMS website if you need more info.
Regards,
RickS

[RobEvo5]

Many thanks for response, unfortunately I didn't receive the calibration cable or dongle with the car. So can't see what's going on, or play with it, without another no doubt considerable outlay

So now trying to take another direction and tried to put back to stock. But I tried the OEM ECU on what is a standard car with MAF connected along with Lambda etc but the car will not start, it feels like it nearly wants to start but it wont, it feels like fuel pump starvation and perhaps not enough fuel getting through to start. So wonder if you are able to help with another question:

Do the loom wires need to be swapped about at all for the gems. Particularily in reference to the fuel pump. Having looked at the manual I notice the fuel pump wire could either be on pin 1 or pin 21. Would these need to be swapped around for the GEMS to work ? or do any other wires need to be swapped about for the gems to work ?.

Thanks again,

[RickS]

Pin A21 is the normal place for the fuel pump and A01 is the Alternate Fuel Pump pin. The unit should be Plug 'n Play, but it maybe worth asking the previous owner if it had been modded in any respect, likewise, unless you're sure it's 'stock', any hardware changes that may have been carried out to the vehicle. You could also send me the S/N (via a PM if you wish) and I could check to see if it's come back to us at anytime to have some work done.
HTH
RickS

[RobEvo5]

I'm still truggling with cold start idle, and also dips rich a bit as it comes on boost then leans out more or less to normal AFR on boost, and generally idles at 13 AFR v's 14.7. I appreciate this is prodominanately a rally bred ECU any may have it limits for mild road manners and road use, and I'm being convinced to ditch my gems and go with another make ECU.

However I don't like to admit defeat, and I could be wrong but I do feel with some patience and time these could be mapped out or at least greatly improved, and having mapped and Apexi ECU for my own use, I'm very temtped to percivere with the Gems a little longer before I give up on trying to make it have normal road manners.

The car will start from cold, but unless I hold it on throttle until water temp gets to 40 deg which take about a minute, it just won't hold idle. My nose and ear and AFR guage tells me the car is just fighting to idle because its running too rich in this area, but the more it gets to working temperature (80/90) the better is gets but even at working temp is still 12.5-13 afr v's ideal 14.7. But does hold idle and sound perfectly fine at this AFR.

So my question now is how much is a dongle and/or a Lead, and subject to price where can I purchase one so I can have a tinker and hopefully get things better. Or am I wasting my time and potential money.

Thanks & Regards

[RickS]

Hi Rob,
Sorry that you're still having hassles getting back to a pseudo stock trim and you'll not get the AFR close to 14.7 without getting that fueling problem being addressed.

Although the GWv4 calibration software is free to download and inspect from the downloads section of our web-site, the retail for the licence dongle is 300GBP and you'll probably need a cable that will also set you back 30GBP.

These items are available from our resellers (see 'Resellers' tab at the top of the page) or from us at sales (at) gems.co.uk but possibly a more viable option if your plan a one-off tune, would be to take it to a GEMS aware dyno shop and have them iron the bugs out for you. Your local reseller should be able to recommend a suitable shop. Best of luck.

RickS