tuning 95's w/ bigstuff3

[jpwalt1987]

I am in the process of trying to tune my freshly broken in engine. I have had the BS3 for a while and ran the last engine with 72's. I had it tuned pretty decent and it idled good too. I switched to 95lb/injs with this buildup. I had to turn the fuel pressure down to 35 vac off and my idle values in the VE chart are in the 6-10 range. I still have a large correction value and it is running very rich(ie smoke out the tail pipe). I know that these injectors are quite a bit larger but it seems that the dynamics are way different too. Any help or advice would be great. I have an aeromotive a1000 pump, accufab regulator w/-6 welded to the bottom and i am using the stock feed line as the return. thanks, jeremy

[turbodave231]

Did you change the injector size in the "Configuration" menu under "Operating Configuration"?

The engine should idle at 14.5 AFR with no problem on 95's

I'm running 160's and the lowest number in the table is 19.

In your Warm-up table MAP vs Coolant table, be sure everything left of 75 degrees is zero. Calibrate this table last.

Dave

[jpwalt1987]

Dave, thanks for the response.... I did change the injector constant to 950(cc's) like it says in the user manual. I dont recall what the numbers in the warmup table are but even after the engine is hot and all the corrections should be finished it still will run rich. I took it out of closed loop to see if things would change. It then would idle at 14.1-15.1. I am gonna go get my laptop now and take a fresh look. jeremy

[turbodave231]

You may have failed the O2 sensor. When they fail, they indicate lean and dump lots of fuel. I have had that problem before.

I'm also using the Bosch sensor from a VW............same as the Innovate LM1......you can buy them anywhere and they are about $60. You just need a new connector or make an adapter from your old sensor and a VW harness connector.

[SPOT MY 6]

Originally Posted by turbodave231

You may have failed the O2 sensor. When they fail, they indicate lean and dump lots of fuel. I have had that problem before.

I'm also using the Bosch sensor from a VW............same as the Innovate LM1......you can buy them anywhere and they are about $60. You just need a new connector or make an adapter from your old sensor and a VW harness connector.

dave,
Do you have a map of the pinouts or are the wire colors the same? Also, I assume you are using the LSU4 (pn 3737) sensor, right? I was going to buy the NTK sensor that comes with the BS3 but if the Bosch works fine I will go that route. Thanks.

[jpwalt1987]

Dave, will this sensor work? Zip Code Entry at PartsAmerica.com

[turbodave231]

The early Gen 1 BS3 ECU used NTK sensors. I don't think you can use the Bosch sensor...........but you should ask John Meany at Bigstuff that question. Maybe a software change.......don't know for sure??

Jeremy, That link didn't take me to a sensor. The sensor is used in late model Jettas and Golfs. Mike at Full Throttle sells the right sensor for a reasonable price. Wire colors and pinouts are identical to the BS3 Bosch sensor.

I took my old BS3 supplied sensor and cut the pigtail off right at the sensor. I bought the harness side connector from Impex foreign car parts

Here is a link to buy harness side connector bodies and terminals:
WBo2 Connector Kit Parts List

[turbodave231]

Jeremy,

I tried to identify what OEM sensor BS3 uses.........but the sensor I got had the numbers ground off (dirty dogs). I haven't seen another connector end like the one BS3 uses.........so I made the adapter pictured above so I could use either the BS3 sensor or the VW Bosch LSU 4.2.

I found out that in a pinch, the BS3 harness connector will mate to the VW connector if you remove the lock on the harness side and zip tie the two halves together. It worked fine until I got the parts to make the adapter.