MR2 3sgte setup

[D15bguy]

I just picked up my Link g4x for my Mr2 turbo. I have a Gen2 3sgte with upgraded turbo kit and full bolt on. Turbo kit is a Garrett gt28rs (disco potatoe) custom manifold with wastegate, custom downpipe with ems powered exhaust. Tcs air intake. Manual boost controller. I still have all the AFM and all the EGR hooked up. 

I do have the IAT sensor, boost solenoid and expansion loom too. My wb02 is coming in as well. So I'm getting rid of all the EGR and AFM.

But in the mean time am I still able to download the base map and start my car without having to install all the extras in order to recalibrate my sensors?

[koracing]

It should be able to start the engine if you input the proper calibration for the OEM map sensor - if memory serves me there is no table specified for the MAF signal in the base map (and who would want to use that anyway?).  The OEM gen2 map sensor changed a little from early to late versions, but a little googling and you can find the voltage versus map signal in some old MR2OC threads.  

That being said: what are you thinking you will need to recalibrate and start up the motor for?  I mean without installing an aftermarket larger range map sensor (3 or 4 bar) I'm not sure what you are hoping to achieve by starting it up on all the stock stuff.  A wideband is pretty much required to make any type of fueling changes which a base map will very likely need, and should be installed at a minimum.  

I wouldn't recommend starting the motor until you at least have a wideband and map sensor installed and calibrated within the link.  It would be possible glean the necessary information to get a reasonable idle if the wideband is installed and the readings visible via a gauge, but not wired into the link as well, but, again, why would someone do that?

[D15bguy]

My stock ecu is fried due to leaky capacitor. Did not want to risk buying another old Toyota ecu for their known leaky capacitor. So I went with getting a stand alone, chose the link. Otherwise I would be fine where I was with stock ecu.

Only needed to fire the car up with the link and move it around my drive way for the mean time. Gets tiring pushing it around by yourself. But now it seems like it only fires up but can't drive it. Way too rich, everytime I blip the throttle it would stall. 

I do have a 14point7 wideband and afr gauge coming in also. I have the boost solenoid that was ordered with ecu. This whole new stand alone ecu opened up the path to push forward with new goals. Gives me no choice to push the limit for my setup on my mr2 "sigh". Looks like I'll wait until I get the wideband hooked up.

[Adamw]

Attach your map and a log of a start up. 

[koracing]

If your oem narrow band is still installed it can be used to at least get a ballpark setting for a base to move a car around by watching when it changes from 1V (rich) to 0v (lean) - but like @adamw says - attach your base map and a pc log of startup (Hit F8 to start logging, stop logging, and the logging menu at the top to save the log file).  With the Narrow band o2 it is theoretically possible that you can enable closed loop stoich trimming as well as long term learning based on the narrow band which may make it run well enough to move the car.

[D15bguy]

Here is the basemap that i loaded with startup and logging. its the st185 version. I have a usdm gen2 3sgte for 93T.

 

 

here is the datalog

PC Datalog - 2020-11-12 6;23;32 pm.llgx

[Adamw]

Can you attach your map, it will have a .pclx file extension.

What size are your injectors?  Have you checked base timing with a timing light?

[D15bguy]

here is the map,

injector size are 440cc. I havent gotten a timing light to check the bas timing. I figure the basemap would be very close. stock ecu had my car ran well before it fried.

 

tunning185.pclx

[Adamw]

It would be strongly recommended to check the base timing - it is highly likely that could be half your problem.  The trigger is the the distributor in these cars and it can be rotated something like 20 cam degrees (40 crank degrees) so no two cars are going to have the same offset.   

Load in the map below which will be closer in terms of fuel and I have adjusted idle control to try to get that to kick in.  

tunning185 V2.pclx

[koracing]

Typically on these engines if the distributor is perfectly centered in the slot, 95% of the time the trigger setting default will be within 1-2 deg, but it should always be checked and corrected with a timing light.  

The RPM is very low which is probably why the MAP reading is hovering around 75kpa, but I would check that your MAP reading is showing a similar value to the BAP when the key is on and engine is off - and if not performing a MAP calibration.  If you try to give it any throttle does the car actually rev or does it die?

Try taking a log with starting the log before the engine starts, and then showing the cranking and startup as well.

[D15bguy]

here is the logging for ignition on, engine off. Second logging is for engine crank to startup. Last file is the basemap.

 

PC Datalog - ignition on engine off.llgx PC Datalog - engine crank.llgx tunning185.pclx

[koracing]

Your map sensor is showing 169kpa when the engine is off - this is very wrong -- approximately the equivalent of about 10psi of positive manifold pressure.  It should be near to identical to the BAP reading of 98.5.  It does drop when you start the motor so it's *moving* with engine vacuum meaning it's working and sending out some type of signal - but the calibration is obviously wrong.  The early and late gen2 did use two different map sensors, however.  You may want to see if the calibration for the ST205 map sensor is closer to 98.5 when key on engine off - this could make a huge difference in how the car runs at the moment.

Here's a modified version of your tune with idle timing control turned on, and a custom guesstimated MAP calibration based on your logs.  Also with closed loop fuel trimming turned on via the oem narrow band oxygen sensor.  If you update your ecu firmware, you can also turn on long term trimming to help with that roughing in of the fuel table.

tuning185 v3.pclx

[koracing]

Do you have a boost gauge?  Can you tell me what it shows when key on engine off, versus when it is idling at 500rpm?  

Rechecking your datalog the map input voltage is 3.92v with key on and engine off.  That would make a 0-5v range (assuming it is linear) of 0kap to 125kpa at 5v.  I'm certain your map sensor is not reporting a correct voltage to the ecu.  You should also double check the primary ground wires on the bottom of the intake manifold as well as the main ground from the transmission to chassis.  By check I mean remove, clean all contact points with scotch-brite or other abrasive to have clean bare metal contact and reattach.  

[Adamw]

Definitely something a bit odd going on with the MAP sensor, but I would still expect some signs of life.  

Can you unplug the MAP sensor just to check that the AN Volt 3 voltage changes.  You can view the voltage in the run-times screen (F12).  Also watch the AN Volt 4 when you unplug the MAP.  I have come across a USDM car once that had an odd pinout that seemed like it was a combination of ST205 & ST185 and we had to move a couple of wires from memory.  It had an air flow meter and many other ST185 features, but the pionout was more ST205.  Dont know if that was just a hacked up old car or factory though.

 

 

[koracing]

It is pretty well known on the gen2 3sgte there are two pinouts.  Early gen2 and late gen2.  The late gen2 is about 2 wires different than the gen3 (st205).  The early is 14 wires different.  At least it is pretty well known in the 3SGTE community.  If your ecu is the later one it is possible the base map's default map sensor pin location is incorrect as that does chang e between the gen2 and gen3.  Notice the pin locations for the PIM (Pressure: Intake Manifold) aka MAP sensor.  "VS" aka Vane Sensor is the Airflow meter signal.  So just changing the Analog 4 to the MAP sensor should solve the MAP issue.  I should have recalled this previously.

 

Yellow boxed pins are the trigger signals.  Blue is the MAP signal.  Green is the AFM aka MAF.  Grey shows the other primary differences on the early gen 2 versus the later pinouts.  

From the Link G4x Help menu pinout for the ST205X:

 

I'm attaching a revised version of your file once again with this change made.

 

[Adamw]

The US terminology is different to what we use here.  What you call "Early Gen 2" we call a V1, this uses the ST185 ECU.  What you call "Late Gen 2" we call V2 and it uses the ST205 ECU.  What you call "Gen 3" we call V3, and it uses the ST205 ECU.  

But this user says he has the ST185 ECU, and his log shows the trigger is working so his car must have the ST185/V1/Early Gen2 pinout.   So Im not sure how your ST205 pinouts are relevant.  Unless there is another odd version like I mentioned finding earlier which uses a mix of the ST185/205 differences..

 

[koracing]

Setting semantics aside for a moment: I don't believe this user ever said that he had a ST185 ecu.  He said he used the ST185 version base map which theoretically should be closer to what his engine is than the ST205 base map.  He did, however, say he has a 1993 USDM Gen2 3SGTE.  1993 would be the first year of the V2 aka late Gen2 in the MR2.  I believe his ecu must be a V2-3 due to the fact that his car would not even try to start if he had the wrong ecu for his pinout.  If we had the part number of his stock ecu that would clear it up definitively.  The bottom line though: If it was able to run fine on an OEM ecu without a bunch of modifications to the harness, it would have to fall in line with one of the 3 versions stated above, and it would be extremely unlikely that it was some odd or unique pinout. 

As far as what you've found in the past, I can only speculate. One theory would be a mismatch of engine and body harnesses. The engine harness has 2 of the ECU connectors and the body harness has the 3rd.  So it is feasibly possible to get some odd mismatch of the right connector from a V1 with a left 2 connectors of V2-3 or vice versa.  This would power up fine with any ecu, and if the ecu matched the engine side harness it would see proper trigger signals, but it would not start up on an OEM ecu.  In this scenario there are other harness issues that would arise (chief among them being a lack of any fuel pump turning on due to no output on the FC pin). 

[Adamw]

3 hours ago, koracing said:

I don't believe this user ever said that he had a ST185 ecu.

Ok, reading it again I think you are right, I assumed he was saying he had a ST185 ECU.    

If he does in fact have a ST205 ecu, then he should be using the ST205 base map - the base map matches the I/O assignment, not the engine.    For Instance with the ST185 map loaded into a ST205 the CE light output will switch off the TVIS solenoid as soon as it starts which wont help it run.  

 

So going back to the OP's problem... 

1. Assuming you do have the ST205 ecu, then load the ST205 map in so that the IO assignment matches the hardware.
2. Re-read the "pre-start configuration" and "first start checks" section of the manual - this would have picked up the wrong MAP pin assignment if it had been done. 
3. Initially increase the master fuel to 20ish like I done in the earlier map to suit the small injectors.  Start it, then once running adjust the master up or down just using your ears for feedback, adjust it in whatever direction gives you an increase in RPM and smoother running.
4. If it still doesnt run reasonable with that then the next step would be to get a timing light on to it to confirm base timing.

[D15bguy]

Just to clarify, I have 93 turbo USDM Gen2 3SGTE with following ecu below.

Stock ECU # 89661-17390

LINK G4X - TST205X

I'm using the ST185 basemap as it would be suitable for my gen2 usdm. I believe my gen2 ecu for the 1993 is a half and half of v2-3. I'm also from Canada so 1993 was the last year production for the MR2.

My link ecu which is the st205x, I can actually start my vehicle up with loading both st185 and st205 maps on. 

The st185 basemap had MAP sensor set to analog 3 and MAF to analog 4. I unplugged the MAP sensor and saw Analog 4 voltage dropped to 0V. I quickly changed the Analog 4 to MAP and it had voltage showing. Calibrate the MAP sensor and it was a success. MAP sensor solved. 

[Adamw]

You should use the ST205 map. This has the IO set up to match your hardware.

[koracing]

Yes I would definitely verify your I/O.  You can change the values in the file you have or start with the ST205X base file.   There's a few differences from what I can see when comparing.