The Official 97+ HO in a Renix Thread

Ok, after battling with this swap and doing a million searches on every forum from here to timbucktoo I've decided to gather and share all the info I've come up with.

My truck is an 89' Renix 5 speed, the donor is an 01' OBDII auto.

Pulling the engine is the easy part, make notes of all your connections as you pull it.

Exhaust Manifolds-
There are a few different exhaust manifolds depending on your model year donor engine. My 01' had the twin exit/twin cat. set up so I swapped it for the stock 89' unit. I would recomend using the manifold that came off your original engine or a header such as Borla, Banks, etc. If you do use a header you will probably have to replace the front pipe and/or add an O2 bung depending on the header you choose.

Intake Manifold-
The HO heads have slightly different ports than the old RENIX engines and the HO intake is worth a few h.p. also. If you choose to use the HO intake and t-body you'll have some wiring to do. I chose to swap the connectors to the newer OBDII connectors for ease of service.

Intake Differences:
Fuel Rail and Regulator (you'll need a 93-94 HO rail and regulator)
Injector connectors (you can re-use your stock injectors)
Idle Air Control Motor (wiring diagram coming soon)
Throttle Position Sensor (if you have an auto Renix, there is an adapter available from HESCO to use the Renix unit, manual can use HO TPS)
Intake Air Tempature Sensor (wiring diagram coming soon)
Throttle Cable (use same year cable as your new engine)
Cruise Control (currently working on this)

Other differences-
Distributor (Use Renix distributor)
Coolant (Gauge) sender (Renix, in cylinder head / HO not there)
Coolant (ECU) sender (Renix in driver's side of block / HO in thermostat housing)
Alternator and mounting (Renix, internally regulated / HO, ECU regulated)
A/C compressor Mounting (Renix, R12 / HO R134)
Power Steering Pump and mounting (Renix, pump was tensioner / HO has seperate tensioner on mounting bracket.)
Pilot Bushing (Advanced Adapters 716159; 1.050 O.D. - .597 I.D., machined down to 1.00 O.D. / This is for both Peugot and early AX15)
Flexplate/Flywheel (Use the Renix unit, along with Renix Crank Position Sensor)
Oil Pressure sender (Use Renix sender)
Serpentine Belt (belt has to be longer to fit Renix alternator and HO power steering/ tensioner set-up. Belt # coming soon!)
Knock Sensor (Renix, driver's side of block / HO doesn't have one)

How to deal with the big differences:

Coolant (gauge) sender: Drill and tap the head to use the Renix unit before installing the engine (more room)

Knock Sensor: Tap the hole that already exist in the block and re-install (I highly recomend a new sensor, to aid performance)

Coolant (ECU) sender, Intake Air Temp sensor, OBDII Injectors: Replace connector to use OBDII parts.

Idle Air Control Motor, Throttle Position Sensor: This is a bit more complicated, I'm currently working on a wiring diagrams to show which wires go where.

Cruise Control: This seems to be a simple matter or re-mounting the actuator where the cable can actuate the throttle body linkage.

If anyone has anything to add, please contact me, I wann get all the info I can in one place.

I'll try and get the wiring diagrams and as many pics as I can posted in the next few days.

This is awesome!!! This is what I plan on doing with my '90. My head is in real bad shape and my engine has about 250k on it, so instead of just replacing the head I plan on getting a newer engine. I have been looking for this info. What year engine would be the best to get? maybe a '93-95? Thanks again for the info!!

I put a 95 into my 90, reused the accessories, but used the HO intake throttle body and exhaust manifold. Just had to make an adaptor to run the Renix TPS on it, everything else bolted right in.

Blue XJ- Did you use the IAC from the HO or from your Renix?

canadian_xj- hope this helps you avoid all the fustration I've gone through

Being a newbee here and at the risk of sounding Stupid, I Thirst for knowledge.
Can some-one please explain HO and Renix, I assume it's types of engs, if so how would I identify them. I have a 93 and an 00 jeep cherokee, both 4.0

Renix refers to the Renault Bendix (=Renix) ignition and computer system used on the 4.0 up to and including 1990. It is a simple system, easy to trouble-shoot with a multimeter. It does not store error codes. Renix 4.0 engines have a slightly more restrictive intake design. They have an EGR and knock sensor, both deleted by Chrysler staring with the HO in 1991. Renix 4.0 engines have a butt-load of low rpm torque- the early HO moved the torque peak from 2500 rpm (Renix) to something like 4000 rpm. Later mods brought the torque peak back down somewhat. The HO engine was used 1991 to 1999. The last iteration used in the XJ in 2000 and 2001 appears to have dropped the HO label, and brought a better-flowing intake and crack-prone (0331 part number) head, with duel exhaust headers (3 cylinders each), two pre-catylytic converters and one main catylytic converter, and FOUR oxygen sensors, and went along with a weaker low-pinion front axle. I drive a 1990 and a 2001. I'm not convinced Chrysler has done anything to improve the Cherokee. That said, I still don't want to switch to anything else.

downshift1 said:

Blue XJ- Did you use the IAC from the HO or from your Renix?

canadian_xj- hope this helps you avoid all the fustration I've gone through

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I honestly don'r remember, but I think it was the one from the HO motor, for some reason I want to say they are different shapes and the Renix one didn't fit the HO throttle body.

Thanks 4xbob for clearing that up for me.

Blue XJ said:

I honestly don'r remember, but I think it was the one from the HO motor, for some reason I want to say they are different shapes and the Renix one didn't fit the HO throttle body.

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I know when I put the 99+ HO intake on my Renix motor I had to use the Renix IAC. That is however retaining the Renix engine and electronics and using just the HO intake manifold, not using an HO motor as well. When I tried running the HO IAC, it only idled at like 200rpms. I also have the belt part number on an O'Reilly's receipt that I'll dig up later tonight for the extended "new" belt routing.

RenixPower said:

I know when I put the 99+ HO intake on my Renix motor I had to use the Renix IAC. That is however retaining the Renix engine and electronics and using just the HO intake manifold, not using an HO motor as well. When I tried running the HO IAC, it only idled at like 200rpms. I also have the belt part number on an O'Reilly's receipt that I'll dig up later tonight for the extended "new" belt routing.

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O.K. if anyone is still checking out this thread....I would love someone to start a new one with a write up about using HO intake with Renix motor. I have an intake lying around and had no idea this was possible...more info please!:shocked:

THIS THREAD IS GREAT
I have a 89 xj and my donor truck is a 91 xj w/a perfectly good motor. does most of this still apply? is it really that simple? I was planning on having to replace the entire harness and computer.
Thanx for the info guys, Jeremy

in2fords said:

THIS THREAD IS GREAT
I have a 89 xj and my donor truck is a 91 xj w/a perfectly good motor. does most of this still apply? is it really that simple? I was planning on having to replace the entire harness and computer.
Thanx for the info guys, Jeremy

Click to expand...

I did exactly that with mine...1991 HO into a 1987 Renix.

I have a manual, I forget the specifics but the resistance values are different between the TPS's. I modified my HO throttle body to accept the Renix TPS, I'll provide details about that if anyone is interested.

In retrospect, it'd be a LOT easier to reuse the Renix manifolds on the HO engine. I suggest you take that course of action, it'll make the new motor pretty much plug-and-play and highly simplify the swap. The Renix intake will work on the older HO engines, but the 97+ HO engines came with a different manifold than the 91-96.

No need to swap harnesses or computers.

Here is a link with all the info I believe you'll need for swapping a 91-95 HO 4.0L into a 87-90 4.0L XJ, I wrote it after I did the swap 1.5 years ago.
http://www.terrainstompers.com/forum/viewtopic.php?t=14

As stated in link above - All electrical components (TPS, CPS, MAP, flywheel, distributor, coil, sensors, etc*) must match the wiring harness & computer system. If you have a 90 XJ; you must use the 90's sensors, or it will not run.

*I am not 100% sure if I used the HO IAC sensor, but I believe that I did, now that I think about it. I believe it plugged right into the renix wire.

If you have a manual tranny, you may need a new pilot bearing to mate between the bore of the crank & the input shaft. Early AX15's used the same size input shaft as the Peugots, but later AX15s used different shafts.
I don't believe you'll need to make a custom TPS adaptor with a manual tranny though!

I am actually swapping in the aw4/231 also. I started w/ a 89 2wd and gathered 2 parts xj's, a 87 aw4/231/hpd30 disco w/ a 4"lift and a 91 4.0/aw4/242/hpd30 non-disco and a spare aw4/231 on the side, a set of 33"s and a awshift 1st gen system. I think I just might have enough parts do do it all I was going to use my renix for now and rebuild the h.o but I messed up the crank while removing the pilot bearing(plasma will do that) so Im just swapping in the h.o now. I am removing the heater/ac under the dash to run a intake filter there(noisy, I know) I might still swap the entire harness while I have it all apart, just need to look at it first.
Thanx for the link, Ill go over it and it will make the decision alot easier.
Jeremy

Cool thread. Still need to ask if and what year will a HO intake and throttle body (with modified sensors) will work on a Renix motor? Will I need to switch exhaust manifold as well or can I eliminate EGR with Renix exhaust

The actual HO-4.0L intake/exhaust header will not bolt right up to a non-HO 4.0L motor.

jfiscus said:

The actual HO-4.0L intake/exhaust header will not bolt right up to a non-HO 4.0L motor.

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That statement is incorrect. Any year intake manifold will bolt onto any year cylinder head. The high output exhaust manifold and down pipe will swap out with the renix exhaust manifold and downpipe. Also any year 4.0 XJ head will bolt to any year 4.0 XJ block.

ok, to answer a few of your questions:

Using a HO intake on a Renix head will net you little or no hp gain due to the fact the intake runners on the cylinder heads are a lot different.

You can use the Renix dual connector TPS for autos, but you need to make or buy an adapter (http://jeepers.biz/shop.asp?action=details&inventoryID=45563&catId=)

you can pretty much bolt up any HO intake manifold to the Renix, but you will have to weld up the EGR hole on the exhaust manifold.

ok, Im not running a comp for the aw4, just the awshift system. I think I will run the full h.o and swap the harness, I will have the dash apart anyway and Im hoping all the connectors under dash are the same.
Thanx for the info, Jeremy

Just to let all you guys know I'm going to hopefully do a write up with tons of pics in the near future as a supplement to this one. I don't know if we can somehow have a mod combine them but I'm thinking I'll atleast have a rough draft of one tomorrow.