ECU mod & poor mileage

[poloquet]

I have a question about kenneth ecu mod v1.02 on automatic i get bad mileage could this be the cause or should i looking for something else

[Nick Mann]

Flash it back to standard and see?

[poloquet]

Would prefer not to. Didn't drive the car for long with stock and had to eliminate a lot of issues including bad maf and collapsed muffler

[lathiat]

Is your tune under KS-MODS the same as a standard rom?

also how did you 'eliminate' the MAF issues? new MAF or some re-tuning?

[poloquet]

New maf. Solved a lot of problem thinking of an EVO Maf.

[wintertidenz]

Check the O2 sensor and replace it - after dumping so much fuel into the engine with a bad MAF, it's probably stuffed.

[poloquet]

We are actually checked it and according to evo scan it is fluctuating quite fine.

[wintertidenz]

Mine looked fine via EvoScan too - but once I pulled it out it was obvious that the sensor was dead, as it was completely full of carbon.

It's worth spending 5 minutes to pull it out and check it anyway.

[poloquet]

When you mean fine via evo scan. Was the voltage fluctuating??? I might just have to take your advice but swamping one in would have to order it. Takes two weeks trying to figure it out.

[wintertidenz]

When on the open road the voltage was where it should be (0.5v) but the car still seemed to be running rich and using a lot of fuel. I only knew it was dead because a) the car had been having problems starting due to the battery, and there was a lot of unburnt fuel in the system which promptly ignited and sent flames down the exhaust and b) fuel economy was out the window.

Any O2 sensor from a Mitsubishi Eclipse should fit - it needs to be a 4 wire sensor, so they may even be fitted to other makes and models of cars that parts are available for you locally.
NGK part # 23559.

In fact, here you go: http://www.ebay.com/itm/NGK-23559-Ox...item3a6fa670cb
Listed as fitting pretty much all USDM Eclipse/3000GTs and some older Diamantes.

[poloquet]

Thanks we only measured it on idle and it was fluctuating up to 0.9 etc. We did have a situation where the exhaust was blocked so this may have caused that. Thanks for the us part number been searching for it high and low

[poloquet]

I think the number is actually ngk 23558

[wintertidenz]

The fitting on the end is actually the one on the post-cat one, NGK 23559.

OEM part # is MD189008.

RockAuto have the part: http://www.rockauto.com/catalog/moreinfo.php?pk=992011
DENSO Part # 2344026.

[poloquet]

so we carry two o2 sensors. I would need the number for both

[wintertidenz]

No - VR4s only have one. It's on the downpipe, just before the cat.

[Davezj]

Personally I would still put the stock rom back in the ecu and verify you are getting about 18-20 mpg round town and 25-28mpg on the motorway, very rough figures as this seem about standard.

As long as the car is in standard factory spec.

[poloquet]

Will try and see if that works. Also we were using 1.02 and wanted to try 1.03 instead. That might be awhile for testing. But mileage is great for long distances just terrible after a hard run and cruising. I think i need to change a few more parts also like fuel filter etc. Any ideas what else. The car was parked for an entire year and had a bad maf before so trying to sort out all things.

[poloquet]

The fitting on the end is actually the one on the post-cat one, NGK 23559.

OEM part # is MD189008.

RockAuto have the part: http://www.rockauto.com/catalog/moreinfo.php?pk=992011
DENSO Part # 2344026.

So can anyone verify this part number from dense as the oxygen sensor. This one is just plug and play right