another renix to HO question

i've pulled the engine/aw4/231 out of my 87 all in one peice.

i've pulled the engine/ax15/231 out of a 93 parts jeep.

i have both units sitting side by side and can switch over anything i need.

i plan on pulling all the sensers off of the renix block and intake and putting them on the HO assembly. my plan as of yet is to use the renix exhaust manifold to avoid alignment problems with the exhaust.


question 1 what is the IAC i keep hearing about, people say you can use the renix or the HO IAC without cause for concern.


question 2 I heard a while back that the TPS off a HO/ax15 will plug straight into the renix without the need for the adapter.


question 3 Do i need to use the renix CPS and how will that be affected with the HO flywheel? cant change the flywheels out because of the whole aw4/ax15 thing.


also was wondering about my reverse lights. is the plug on the ax15 the same as the one on the aw4 and where does it come out of the transmission?

The plug for the reverse lights is not the same. On the AW4, it is a part of the neutral safety switch. The AX15 will not have an NSS.

IF you are staying Renix--computer, entire harness, sensors--then you HAVE to have a Renix flywheel/flexplate and CPS/CKP. The HO (OBDI and OBDII) are not interchangeable with Renix.

The Renix throttle body is different than the HO, the Renix TPS is adjustable, the HO is not. As far as the IAC, just look up both years on rockauto.com, same part number, then it is interchangeable.

Yes, you can use either IAC motor.

Yes, you should need the tps adaptor from Hesco, or make one...

You must use Renix CKP and flywheel, or HO CKP and flywheel...are not interchangable

89xjgrey said:

Yes, you can use either IAC motor.

Yes, you should need the tps adaptor from Hesco, or make one...

You must use Renix CKP and flywheel, or HO CKP and flywheel...are not interchangable

Click to expand...

The CPS/CKP and flywheel/flexplate HAS TO MATCH the ECU/PCM and harness.

You cannot use an HO flywheel/flexplate, with an HO CPS/CKP, and expect it to run with a Renix ECU.

I used the 91-99 stock exhaust manifold-but used a down pipe for a 91-which will bolt right up to the factory converter 4 bolt flange.

joe_peters said:

The CPS/CKP and flywheel/flexplate HAS TO MATCH the ECU/PCM and harness.

You cannot use an HO flywheel/flexplate, with an HO CPS/CKP, and expect it to run with a Renix ECU.

Click to expand...

On the contrary, I have successfully ran an engine using an HO CKP sensor and HP flexplate and HO CKP sensor pigtail spliced into the renix harness using the Renix ECU.

so it looks like i'm into the TPS adapter for sure and i'm going to give the splice job a shot for the CPS.

i'll just leave the HO senser with the engine instead of switching like i was going to.

on the ax15 where are the wires for the backup lights and which color does what, if anyone has that info.

or does it just complete a circuit.

(which i'm assuming is the same issue with the 4wd sensor in the Xcase)

If you are intending to use the HO intake and the Renix exhaust, note that the Renix system has an EGR valve with a tube going from intake to exhaust. The HO intake does not allow this system to be used, as there is no hole for it. If you must use the HO intake, this EGR system must go away. Please be aware that this system is considered an emissions part, so removing it is not legal - If you use this vehicle on the road and need to pass inspections, you cannot use an HO intake manifold. While the exhaust header can be swapped between heads, the intake ports do not exactly match, so in order to use the Renix intake, you must also use the Renix head. There was a thread on here about grinding the head so that the ports do not block the injectors when using a Renix intake, but the best way would be swapping heads. All that being said, I am running a 93 HO in my 87, using the 93 head and intake, with an 87 header. I welded a piece of steel over the EGR hole in the header. The fact that the camshaft changed in 91 to remove the need for an EGR system is irrelevant in the eyes of inspectors, since the vehicle is still an 87. Don't get in trouble.

Other things to deal with would be the temp sensor in the Renix block, and the absence of a hole for it in the 93 block. The 93 has a T-stat housing with a threaded hole in it, and I believe this is where said sensor is now located on mine. You need the 87 alternator. TPS adaptor is needed for the Renix TPS if you're using the HO TB, make one or buy one from Hesco, I made my own. You also need the 87 fuel injectors (it will run with the 93 injectors, but you will get around 10 mpg). They will fit in the 93 fuel rail/intake. You need to modify the fuel lines a little bit to get them to hook up to the 93 rail. I just added a bit of regular fuel line and clamped it on, deleting all the "quick connectors." Install and properly index the Renix distributor on the 93 engine. Use spark plugs that match the head you are using.

Also, due to the extreme difference I saw between the Renix and HO flexplates, I find it hard to believe that an HO flywheel would work by simply using the HO CPS, the hole pattern is completely different. Since in your case this would involve buying a new flywheel, maybe it's worth a try. It will not start if it is wrong, as this is what tells it where the crank is at. I ended up removing the engine/trans/tcase a second time to replace my flexplate. It was easy to swap when the engine is out of the vehicle, but in your case you're gonna have to buy the flywheel if you can't somehow rig it to work.

That's about all I can think of right now. It's easy, in a hard, frustrating sort of way

Good luck.

Depending on the location, if you have the newer motor installed(and the necessary smog equip., you can take it to a ref and have them inspect/certify it.

well if the flywheel was easier to get to and i wasnt leaving driving across the country in less than a week i would probably give it a shot but just to be on the safe side it looks like i'll be buying a flywheel.

and also someone scabbed my TPS off my jeep while it was sitting so now i'll need to buy a renix tps also...