jeep renix system--no start

crash2 · Jul 9, 2007

So for a little back ground--the 4.0 came out of joe's XJ and it was a running deal. Now when I seperated the 4.0 from the auot tranny I forgot to remove the cps and it broke. Now in the new setup we have a manual trans.

So now I wired up the 4.0 in joes YJ --intergrating the renix system in the YJ(which was origionally a 4 popper) and removing the origional main connector between the 4.0 and ecm harness.

So now the rig don't start. I know for a fact it does not have injector pulse or spark.

Here is what I have done.

The new cps origionally only put out .120Mv ac--From alot of reading I knew that was not enough(this is with a brand new cps). First thing I did was polish the reluctor portion of the flywheel and also ended up notching the cps to get it closer to the flywheel. So now I am getting around .650Mv ac which from what I have read normal is around .5-.8 AC.

So my next step was to confirm my wiring--which I spent close to 4 hours checking every single voltage/ground/continuaity/shorted to other circuits. The only thing I did not confirm was the output of both temp sensors.. But yet I have no injector pulse/spark.

So I am thinking of a problem with the ecm--which I opened to make sure nothing was physically melted.

So has anybody had an ecm fail on one of these(bendix ecm)

jeeptech 1 · Jul 9, 2007

Must use the 4.0 manual flywheel,if you did have you checked to see if the new crank sensor is puting out a signal?Check at the connector at senor and at tha ecm/pcm I can get the terminal connector pin location, pm me if needed P.S. The senor wheel on the fly wheel have been know to spin if you resurface the flywheel. Good luck Or PM Me.

TMFabrication · Jul 10, 2007

You'll need to use the 4.0 flywheel and a bellhousing from a 4.0 manual trans because the CPS hole is in a different location on the 2.5. Your best bet is to run a Hessco harmonic balancer and new cps that bolts to the front cover http://www.hesco.us/shop.asp?action=details&inventoryID=43097&catId=7902

http://www.hesco.us/shop.asp?action=details&inventoryID=43098&catId=7902

crash2 · Jul 10, 2007

TMFabrication said:
You'll need to use the 4.0 flywheel and a bellhousing from a 4.0 manual trans because the CPS hole is in a different location on the 2.5. Your best bet is to run a Hessco harmonic balancer and new cps that bolts to the front cover http://www.hesco.us/shop.asp?action=details&inventoryID=43097&catId=7902

http://www.hesco.us/shop.asp?action=details&inventoryID=43098&catId=7902

Thats just it though--everything is matched as it should be and I am getting over 1/2 volt a/c...

Moneypit1 · Jul 10, 2007

Mike,

What flywheel are you using? Did it come from a Renix system or a HO system?

crash2 · Jul 10, 2007

Moneypit said:
Mike,

What flywheel are you using? Did it come from a Renix system or a HO system?

That I don't know. but I would figure since I am getting what I have found to be a decent output a mute point I would think.

Anybody know what kind of data can be had with a scanner on this particular system? From what I have read its pretty poor..

TMFabrication · Jul 10, 2007

What year is the 4.0 and what year and model is the tranny? is the fly wheel original to the 4.0? The YJ was a 2.5, right?

crash2 · Jul 10, 2007

TMFabrication said:
What year is the 4.0 and what year and model is the tranny? is the fly wheel original to the 4.0? The YJ was a 2.5, right?

The tranny I think is an ax something :redneck: The flywheel came off what the tranny came out of. The YJ was a 2.5 but thats a mute point since the motor has never been there for me..

But the one and only change from what the motor/harness/ecm is the tranny/relucter..

TMFabrication · Jul 10, 2007

ax-15, I think. If the flywheel and tranny are from a 2.5, you'll have to change the flywheel and bell housing to make it work or get the hesco set-up. IIRC the computer needs to see the crank and cam signal sync to send signal to the coil and injectors. Is the tranny original to the Jeep? The ax-15 (I think that is the model) was used behind both the 2.5 and 4.0.

bharris68 · Jul 10, 2007

AX-5 behind 2.5, AX-15 behind 4.0 IIRC.

Cascade_Crawler · Jul 10, 2007

bharris68 said:
AX-5 behind 2.5, AX-15 behind 4.0 IIRC.

this is correct. If its an ax15, and your using that flywheel, its the correct one for use with the 4.0

crash2 · Jul 10, 2007

So did they change the crank sensor setup on the 91-later models?

crash2 · Jul 10, 2007

TMFabrication said:
ax-15, I think. If the flywheel and tranny are from a 2.5, you'll have to change the flywheel and bell housing to make it work or get the hesco set-up. IIRC the computer needs to see the crank and cam signal sync to send signal to the coil and injectors. Is the tranny original to the Jeep? The ax-15 (I think that is the model) was used behind both the 2.5 and 4.0.

Everything should be matched correctly. Joe had a # of months to do his homework and I am pretty sure he got right. As for the workings of the system its just a typical sequential setup--uses the cam to refernce #1 and then the crank is the rpm input--not much different from the Gm stuff from what I can tell...

Avanteone · Jul 10, 2007

crash said:
So did they change the crank sensor setup on the 91-later models?

Yes.

The '87-90 Flywheels are different than the '91+. They have a different number of "grooves" cut in them for the crank sensor to count or trigger from. The '87-90 has cut outs all the way around (probably a hundred or better) in a continuous pattern. The HO flywheel '91+ has 3 sets of 4 notches around it's circumference. If this is the flywheel/trans. that I'm thinking of that Joe bought from me it may have the incorrect flywheel installed.

J

crash2 · Jul 10, 2007

Avanteone said:
Yes.

The '87-90 Flywheels are different than the '91+. They have a different number of "grooves" cut in them for the crank sensor to count or trigger from. The '87-90 has cut outs all the way around (probably a hundred or better) in a continuous pattern. The HO flywheel '91+ has 3 sets of 4 notches around it's circumference. If this is the flywheel/trans. that I'm thinking of that Joe bought from me it may have the incorrect flywheel installed.

J

I think you are correct john--I did notice the groves are not continuous and have spacing between them

Thanks john--I think that was the info I was looking for.

But what gets me is the voltage is still over half a volt but there must be something else to it that I cannot see.

crash2 · Jul 10, 2007

Oh one other thing--is the only difference the relucter ring?

Six-Nine · Jul 10, 2007

Avanteone said:
Yes.

The '87-90 Flywheels are different than the '91+. They have a different number of "grooves" cut in them for the crank sensor to count or trigger from. The '87-90 has cut outs all the way around (probably a hundred or better) in a continuous pattern. The HO flywheel '91+ has 3 sets of 4 notches around it's circumference. If this is the flywheel/trans. that I'm thinking of that Joe bought from me it may have the incorrect flywheel installed.

J

So you got one of the renix flywheels laying around?

Six-Nine · Jul 10, 2007

crash said:
I think you are correct john--I did notice the groves are not continuous and have spacing between them

Thanks john--I think that was the info I was looking for.

But what gets me is the voltage is still over half a volt but there must be something else to it that I cannot see.

The renix computer isn't reading the H.O flywheel? So what you wanna do, if you want I can call hesco in the am...be a lot easier than R&Ring the drivetrain.

Avanteone · Jul 10, 2007

crash said:
Oh one other thing--is the only difference the relucter ring?

Kind of. The grooves are all cast/machined into the flywheel. Can't change just the ring or anything. The hesco kit to reposition the CPS to the front of the engine will be the EASIEST fix. You will still have voltage but if you were to actually watch the pattern on a Vantage or other graphing device it wouldn't be correct for this application. I have a renix flywheel if that's what you decide to do.

J