• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Are all IAC's the same?

C

clunk

NAXJA Forum User
Location
West Kootenays, BC (canada)
I was at the wrecker today looking for a TPS..someone had already beat me to the TPS. There was another XJ with a standard tranny that still had the IAC intact so I grabbed it for $5.

Now, the question:
The IAC came out of a 5spd and I have an auto, does this matter?
The jeep may or may not have been a newer model..the thing was so trashed I couldn't tell any more. If it was a newer(post renix) model, will the IAC still work?
I compared it to the one that was in my jeep already and the pintle seemed to be a bit longer. I replaced mine with the one I got at the wrecker because it looked alot newer and I figured "why not". The engine seems to run a little lower in RPM's at idle and at hot idle drops down to around 400-500 which is a little lower than with the old IAC.
Is this new one okay to use?
thanks!
 
I wonder the same thing because the Holley IAC has a different pintle than the RENIX IAC, so I wonder if the Holley unit will work on a later model? I bought the Holley unit for my RENIX and it will not idle with it in so now I'm stuck with the extra IAC, maybe it will fit my 96'?
 
The way I tend to check these things is to go to Autozone or the like and look up the part on both models, then compare the part numbers.
 
well I just left the new IAC in there and drove around 30km's earlier tonight. I didn't notice any problems except that my acceleration seemed to be a bit "smoother". This was probably because the old IAC unit was worn out, and even though I cleaned it a few weeks ago and got all the junk out of it it was probably on it's last legs. Seems to be interchangeable and now that the computer has "adjusted" to the new IAC it seems to be idling at normal speeds as well.
Now, to fix that TPS...
 
xjtrailrider said:
I wonder the same thing because the Holley IAC has a different pintle than the RENIX IAC, so I wonder if the Holley unit will work on a later model? I bought the Holley unit for my RENIX and it will not idle with it in so now I'm stuck with the extra IAC, maybe it will fit my 96'?
Click to expand...


Hey - Can I get a confirmation from ya on that Holley IAC part number?

Had someone else indicate that Holley part #543-105 (idle air control motor for Holley's pro-injection system) would work. If it's the same number then I need to update some info... if it's a different # then maybe the # I've listed will help ya.
 
I recently saw two different pictures of the IACs for 1990 and 1991 (I think it was those years) and one was longer than the other, and one was thicker than the other making me think there is a real difference between OBDI and renix IACs. There was a change in the throttle bodies then when the HO engine was introduced.
 
I know for a fact (backing up Ecomike's theory) Renix and HO IACs differ because of the pintle length especially. I've tried running an HO one with the Renix computer system (I have an HO intake and tb) and it runs like absolute crap. I believe all HO ones are the same although I know the dealer lists several different numbers for them. That Holley one that is like $40.00 at most parts stores is the correct one for sure for the OBD-I and possibly later.
 
So I take it that the mount is the same for the 2 but that the sensor is different? i went to the auto parts store and there were 2 different #'s for mine and they were about $40.00 apart from one another.
 
1985xjlaredo said:
So I take it that the mount is the same for the 2 but that the sensor is different? i went to the auto parts store and there were 2 different #'s for mine and they were about $40.00 apart from one another.
Click to expand...
Yeah the mount is the same and they look physically the same until the pintle is extended. The Renix IAC is much more expensive than the HO Holley one, about $40.00 like you said.
 
The HO IAC will plug into a RENIX harness but the pintle is different and it will not let the RENIX idle. It will rev high on start up and then fall off and quite.
 
xjtrailrider said:
The HO IAC will plug into a RENIX harness but the pintle is different and it will not let the RENIX idle. It will rev high on start up and then fall off and quite.
Click to expand...
Yes those were similar symptoms to what I had.
 
1985xjlaredo said:
So I take it that the mount is the same for the 2 but that the sensor is different? i went to the auto parts store and there were 2 different #'s for mine and they were about $40.00 apart from one another.
Click to expand...

Just to clarify a minor point the IAC is not actully a sensor, it is a motorized control valve.

Sensors collect data and report data back to the central computer, the computer crunches the data, analyses the data and then tells control devices, like the IAC and the fuel injectors, what to do and how much of it to do and for how long to do it. Not trying to be picky, just informative as the better you understand these devices and what they do the easier it becomes to debug the entire system when the gremlins come calling!
 
So does that holley IAC work for a RENIX engine system? We have conflicting reports and I'd like to know before wasting money.
 
mattbred said:
So does that holley IAC work for a RENIX engine system? We have conflicting reports and I'd like to know before wasting money.
Click to expand...

No it did not work with my 90' RENIX, I put the same Holley IAC in my 96 and it works fine!

The pintle is different between the RENIX era and OBD1/2. I'm not sure exactly wich year the pintle was changed. My 94' has the same IAC as my 96' and 00', my 90 like I stated before is different.
 
Can someone who has both post up some pics because I'm still confused, maybe even more confused if that were possible. Pics of the long vs short pintle would be quite helpful. Thanks.
 
xjtrailrider said:
No it did not work with my 90' RENIX, I put the same Holley IAC in my 96 and it works fine!

The pintle is different between the RENIX era and OBD1/2. I'm not sure exactly wich year the pintle was changed. My 94' has the same IAC as my 96' and 00', my 90 like I stated before is different.
Click to expand...

The Renix pintle was used in 87 through 90, OBD-I replaced the Renix in 1991.
 
Sorry to dig up this old thread, but i have a question along the same lines.

Does anyone know if the IAC's for the 87-90 and 91+ are Electronically different?

The reason why i ask is because i am using a Dodge Dakota TB on my Stroker, and the IAC Pintle for the RENIX computer is to small for the TB opening. The IAC Pintle for a 91+ is bigger and fits in the TB just fine.

I was taking the Pintle off of the 91+ and using it inside the RENIX IAC. This worked fine for quite some time, but now im having a low idle issue and my concearn is that this is an artifact of removing the Pintle. My assumption is that the pintle probably shouldnt be removed from the IAC..

Hence my question.. if they are electronically the same (meaning the RENIX computer can talk to the motor and push/retract the pintle) then i may purchase the Holley IAC and give that one a shot.

Thanks!
 
If they are physically the same on the electronic connector they may be swappable, but you should check the FSM wiring on both to see if they swapped any wire pairs?

As I recall the pintle is held in a specific location on the the theaed rod by loctite, and that location is not marked on the rod, so it is hit or miss locating and keeping the pintle in the sweet spot, which may be different for the OBD-I pintle versus the Renix pintle.

I would think, that since the IAC is a reversable DC step motor, that at worst you might need to swap wires around. Also check that the step voltage is the same.
 
Last edited:
You must log in or register to reply here.

Similar threads

I
High idle, smells like gas, running out of things to replace
Replies
2
Views
2K
Inverhyt
I
P
2K IDLE - Odd Shifting - TPS? (I know.. I know)
Replies
3
Views
2K
Unclewolverine
U
F
Stumped on this one!
2
Replies
29
Views
4K
Bent
Bent
V
High temp woes
2
Replies
21
Views
418
Vitzaa
V
S
All D30 lockers the same?
Replies
9
Views
471
RCP Phx
R
Back
Top