Hi from the land of the long white cloud (New Zealand)

Ok guys (and gals) a trick one for you (and a first time post to!). I have a 1996 Lt1 (from a corvette) partial VIN #1T5109497, run by a 1994/1995 PCM, part #16188051. The PCM has a VIN #2G1FP32P4R2160355 the whole shebang is in a 1993 full time 4wd, 5 speed manual (Toyota gearbox) VX landcruiser.

The engine has had ALL the emission stuff physically removed (EGR, EVAP, AIR etc) Air con is the standard Toyota set up and control. Engine cooling fans (2 off) are controlled directly via 2 thermal switches (no PCM intervention). The engine has no MAF sensor. Supposedly a STD Bin is in the PCM. Custom headers are being run (with 4 wire O2’s), throttle body is std. Vehicle was purchased as described.

I have been through shoeboxes site (great site very informative) and checked against the PCM wiring diagram what is connected and what is not. Things that are NOT connected…
· A/C evap temp sensor
· A/C refrigerant pressure sensor
· VSS signals ground and output
· MAF sensor
· EGR vac control solenoid
· EVAP canister purge control
· Reverse inhibit solenoid control
· Skip shift solenoid control
· Performance switch signal
· Performance mode indicator.
· EBTCM sensor
· Traction control spark retard
· Traction control active signal
· Fuel enable signal(no VAT runs on the vehicle)
· MALF lamp
· SKIP Shift lamp
· Park neutral position signal
· A/C request signal
· A/C clutch control
· A/C clutch status
· Sensor ground A/C
· A/C refrigerant pressure
· 5 volt ref.
· A/C evap signal
· A/C cooling fan control
· Primary cooling.
· NO TRANSMISSION SIGNALS OR SOLENOIDS ARE CONNECTED.

I have a copy of the $EE datamaster program and have some logged runs. I am awaiting arrival of Tunercat.

Things I have noticed, Does not go outside mode 16,17,18 (No VSS sensor?). It also does the occasional fast idle (2k RPM) at start up warm. (Has a brand new IAC). I notice from the datamaster file that it does this whenever the IAC parks at a count of 130 at shut down. Also sometimes when warm idle drops to 450rpm (idle rpm that was set using ALDL a, b short etc) IAC counts are reading 3 or 0 (normally after a good blat). Target idle is 800 RPM. IAC has been replaced; TPS is reading ok, map is functioning ok.

I guess the questions I want to ask are? -What needs to be done to the BIN to make all this work nicely together (does any one have one that may be close to what I need?). I realise that some of the items that are not connected can be disabled using tuner cat (to eliminate the MALF codes etc) Can the need for a VSS be deactivated or do I need to install one.

Thanks for your patience; LT1’s are few and far between down here and so are the knowledgeable Chevy people.

 

I would think if you do not have a MAF and you are using a 94/95 PCM with a stock bin then the car is stuck in open loop and that is why you are only using those cells (16-18).

Tunercat can be used to tell the car too run without a MAF (Speed Density mode) by enabling a switch. Weither or not this enables close loop operation after doing so is unknown to me. I bet it does though. The pcm would then look at the MAP and IAT directly to calculate air flow instead of using it as a limp mode for when the MAF is not functioning or not there.

 

Thanks for repling poor man.

The PCM is running in open and closed loop as is expected when it is cold and then warms up. (data master file shows this)

As luck would have it, tuner cat license arrived yesterday. I disabled all the relevant switches and the only malf i have now is malf 11-Mil lamp fault. I have done some researching in the archives and on other conversion sites and it would appear I NEED the VSS signal( it affects fans which i want to change back to PCM control, Idle control, fuel economy and allows the PCM to run out of mode 18 under genral driving conditions). So its either find somewhere to purchase one that suits my application(toyota style mount with an out put for a speedo cable) or I will make a reluctor plate and mount a GM reluctor on the inside of the output shaft housing on the gear box.

Will post how I am getting on

Thanks

 

Paul maybe this would work for you:

https://shell7.tdl.com/~jags/v8-s10-...fferential.pdf

Another member installed it on his 95 F body with a TH350 transplant. He too needed a VSS signal and this was the trick.