Did you drill the CPS upper hole?

 

He tried the mod on his first one, no go, then installed a new Echlin, still at .28. I'm wondering how hard it is to verify he has a Renix flex plate, not an HO. I believe the HO will trigger a renix ECU, just not correctly.

 

Somebody sticking an engine, post 90, into an 87-90 Jeep might not know that they needed to put the flywheel/flex-plate from the earlier Jeep in there. The > 90 HO is different.
The Renix Hall Effect Transducer, needs the correct notches. The HO flywheel/flexplate ALSO, has notches 120* apart, but will not run right with a Renix ECU. The AC Voltage output from the CPS will not be right.

A Renix has a Knock sensor down near the CTS. (the HO has a place for it, but if it's not there, that's an easy clue). The block casting # on an 87-90, is 53005535, on the left side forward of the engine mount. (91>95, 53008405, 96>99 53020596)

Somebody can correct me if I'm wrong here, but I can easily pictute someone doing an engine swap, not knowing they needed to change the flex-plate.

 

Happens all the time. One of the reasons I wrote the following:

FWIW, knock sensor will NEVER cause a driveability problem.

Cruiser’s HO into Renix Swap

This swap is easier than some will lead you to believe, generally those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it as swapping in a long block.

The HO and Renix have some differences but none that can’t be overcome very easily.

Any HO engine from an XJ or ZJ through 1999 can be used. One running change was that the rear of the head was no longer drilled and tapped for the temperature gauge sender beginning in the 96 model year. The sender can be relocated to the threaded hole in the thermostat housing taken from the HO engine. You’ll have to extend the wire to that location. Some brave souls even drill and tap the HO head for the sender.

You will be using the intake and exhaust manifolds from your Renix, along with all your sensors and wiring. Since the intake ports of the HO are slightly different, you use the Renix gasket. Exhaust ports are identical.
You will need to use your Renix distributor as it is different than the HO because they use different fuel management systems. The flywheel or flexplate from the Renix must be used so your CPS gets the correct signals. The valve cover from the Renix allows you to keep your CCV system intact and requires no modifications.

The HO block will have a plug in the coolant galley on the driver’s side of the block, closest to the front, which needs to be removed so your Coolant Temp Sensor can be installed in it’s place just as it is on the Renix. It requires a 5/16” square drive or a modified 3/8” drive that has been ground down to fit. Do this before installing the engine.

As for the knock sensor, which is located just above the oil pan on the driver’s side of the engine about mid way, all the blocks I’ve seen are threaded for it. If not, I’ve heard they may be drilled but not tapped. Tap the hole if that’s the case.


Revised 03/28/13

 

So glad I asked before I did mine. Thank you Cruiser and Flintstone....

 

I will try and double check that this weekend. Everything I have done has made it just a little smoother. I am starting to be curious about the torque converter. I have heard of torque converters going bad on other vehicles and causing vibrations. It does it in park as well as in gear, however is it much worse when in gear. Just a thought....

 

Doing the dynamic compression test I explain in post #7 would tell you if you have cylinders not firing. (or are weak). I believe the pairs the CPS reads are the ones opposite on the dizzy. 1-6, 5-2, 3-4. Would be interesting if was one of those pairs. That would point away from the torque converter.

This is my first crack at posting a U-Tube, and making a noid light with paper-clips and a 3 cell Mag light bulb. #2 injector is getting power> https://www.youtube.com/watch?v=nPdk...ature=youtu.be

 

I borrowed one of those inline test lights that go between the plug and wire and ran a check and they all fired bright. I know this truck was running horrible when I got it, and I have put another 2k mi on it since I have had it as I am working on it. The confusing thing there is that all the plugs are colored so close to the same and each plug has the appearance that the cylinders are running healthy. Usually I have seen one plug really colored differently if there is a problem on that cylinder.

 

What brand of spark plugs?

C101 connector still there?

 

Even a napa or dealer CPS may need a little lovin to make them work right. It happened to me with a genuine Mopar CPS. Try it, you might be suprised.

 

I get it that you have plenty on your plate, they are all getten fire, and that your plugs look good and even. Still, if it's missen at idle, it will only take a few minutes to nail which one(s), by going around the cap pulling one wire at a time. (much more easily done without getting zapped if you loosen them first!). My CPS seemed to work at only .3, but started messing up when it dropped into the .2 range.