[PSIG]

all together at a common isolated point, and not to the battery, yes?

Yes. For this to work properly, check, clean and test your primary block-to-ground cable first, then all your other vehicle grounds. There are likely several of them, and the sources of most electrical issues, including noise.

[Zipdrive]

PSIG, thank you for all of your guidance!

One of the last things I think I need info wise before I atemp to start the vehicle, is what are the settings for the idle to work properly in tuner studio? It is a 4 wire stepper, but I don't know how many steps or anything else about it. So far I have it setup as:

Stepper
Open Loop

Everything else is "factory" tuner studio. Should I change any of the settings for the 4.0L to work "better"?

[PSIG]

I use the throttle stop screw for idle air (like adjusting a carburetor idle speed) for first start and initial warmup to tune idle, where I can experiment with the IAC settings when running with stable idle. This means ensuring the IAC is closed and then unplugged so it doesn't try to alter rpm until you're ready for it. Of course test key-on for IAC movement and direction to home in order to close it at first.

I start with 10ms steps, to be sure it moves when I get the right wiring - but don't leave it there as it will be slow and get hot until you can adjust the step time lower, until it stops moving, then back up 1ms. Each stepper is its own animal, and I have not found any universal settings that 'work' every or even most times.

[TxBxSx]

Zip,

Similar issues have brought me here with my 94 4.0 XJ. There is most certainly a short somewhere that I believe is related to the ECU. I have found that I have both lost and restored ignition signal by something as simple as slamming the door, lol. I'd like to make sure that these issues are addressed before the next build stage of the vehicle.

I am planning to undertake a high compression stroker build. I'd like to run E85, but also know that there will be lots of travel into areas where not only is E85 not available, but 93 octane runs shy also. That being said, the ability to alter fuel map/ignition timing seems like it would be critical to the longevity of this type of build. I thought I would start educating myself by building a standalone harness for the existing setup using a Speeduino in preparation for a more refined solution later on down the road.

I'll be following your build and hopefully we will be able to bounce some ideas off of each other.

[Zipdrive]

PSIG, thank you for your help through this build. There are no adj screws on the throttle plate, so everything is adjusted through the idle control motor. So, If I can get it started..... then I'll start tuning the idle control motor.

I believe that I have setup the controller properly through tuner studio. I did upgrade to the registered version so I could get the output of the crank and cam sensors. So, some questions.

Motor cranks and no start. Fuel and spark are present.

* The angle that I used for trigger angle is 114 based upon a timing schematic I found for the 4.0l jeep motor. I'm a little confused by it though, as the diagram shows cylinder 1 at the end of the sequence vs, the beginning. Should the value be 714 degs? Pic in the next reply.

* what other items are preventing me from starting the engine? Does anyone have a base map that I can compare and start with?

[Zipdrive]

Injector timing diagram 4.0l Jeep

[Zipdrive]

TxBxSx, the ecus on these vehicles are getting to the point where getting junk yard ones don't help. I also found that on our power distrubution box, the socket for the output pin of the ASD relay is "loose". Currently, I have bypassed the relay and bent the 1/4" spade so that there is good connection at all times.

Engine builds are fun. Done way too many for others and at some point hope to do a build for my self. High compression has a very cool "snap" to it. I have found designing a n/a motor for multi fuels is tough (e85 vs 91). Turbos seem to be a little more adaptable. I had a N63Tu which I ran e30 blend in it and it ran really well vs 91.

For the harness on this build, it will be in 2 phases. The first one (current) is all of the connections are at the ECU harness plug on the factory wiring harness. Phase 2 is to build out a new harness, cause most of the old connectors are missing the connector latches keeping everything water tight and connected.... minor details.

When this is "running", I'll put the base map into the github for others to use.

[TxBxSx]

Zip,

Assuming its ok to cross post forums here, see if this helps:

https://www.msextra.com/forums/viewtopi ... a3be038edb

Seeing that Megasquirt users are running Tuner Studio as well, you might be able to track down a base map through those guys. I'm guessing that due to the age of the thread, the log files previously posted are gone.

[Zipdrive]

Tx, yeah, I have started to read through some of there posts, as there are a "few" more 4.0l Jeeps questions on that forum.

One question I have after reading a few of the posts is, does tuner studio make a "base" map based on engine inputs? I.e the maps should be close enough for the motor to start?

[PSIG]

One question I have after reading a few of the posts is, does tuner studio make a "base" map based on engine inputs? I.e the maps should be close enough for the motor to start?

My experience is if I configure as many TS settings as possible, with values reasonably close to reality, the engine will start and run. I also pre-set as much as possible before cranking, such as timing offsets, fuel system priming, etc. Perhaps ugly running, and it may need considerable help and coaxing to begin the warmup, but rarely will it not start at all. I have to watch for signs of needing more fuel or more air, etc.

As it warms, I can jump-in with temporary bumps up or down in global settings such as Req_fuel, WUE, or shift the entire VE Table up or down, in order to smooth the run to warm. At that point I can immediately begin basic rough tuning for idle and stabilize the run. Now I can take my time and progressively build the tune foundation from there with warm restart tuning (cold starts are based on warm idle and warm start settings) and move to increasing load and speed. Hope that helps!