idle

is there a way to adjust the idle speed on a renix motor?

not sure...do you idle too high or too low? Idle is mostly controlled by vaccums and if you have a leak it will cause poor idle.

We are almost neighbors...I live in North Knoxville.

it idle's to low to the point that it dies sometimes. there are no vacuum leaks.
i live in south clinton. do you know jason cooper?

commandtoad said:

it idle's to low to the point that it dies sometimes. there are no vacuum leaks.
i live in south clinton. do you know jason cooper?

Click to expand...

Don't know Jason Cooper. I live off Merchants Drive. If you want to bring it by sometime just shoot me a PM.
JOE

On the base of your throttle body there is a soft metal plug if you remove it (drill,dremel,die grinder) there is a torx screw. in for low idle,out for high. try adjusting it in increments.Make sure you have no vacuum leaks first.

The idle adjustment on the throttle body is to set "minimum air", which is critical to the correct relationship between throttle and the "throttle position sensor"(TPS). If you have incorrect idle, something else is wrong. I would not try to correct an idle issue with the minimum air adjustment. The computer sets idle speed primarily based on coolant temperature. It uses the "air idle control" (AIC) to increase or decrease the amount of air allowed to bypass the throttle plate. When you first start a Renix system, you should get an instant high idle, rapidly adjusting to engine temperature. If you don't, then suspect a bad AIC or connections to the AIC or computer.
Give a clearer picture of what you're experiencing.

joe, my jeep does't really drive on the road, at least not that far.


bubba, thanks for the reply. i should probally mention that this is a stroker motor and when it was installed i put all new sensors on it. a vacuum leak is the first thing i thought of as well but have not been able to find one. it starts like it should, revving up slightly and setting down, just to far down. i know not to mess with the throtle stop, but like you said the computer determins idle, so i was looking for a way to do or check that. a scan tool was my first thought but i have heard that they are rare. to give a clearer picture it dies most frequently when going from a gear to N or P.

From my understanding, the Renix "scan" tool basically monitors voltages. You can get the same info using a digital volt/ohm meter. But I do recall the dealer has a special tool to drive the AIC in and out for test purposes. The only testing I was able to do with my old Renix AIC was to put a small led test light across each set of wires running to the ECM. If the light blinks, it indicates harness is probably good and that the ECM is attempting to control the AIC; you just don't know if the pulse train being sent is correct. I beleive when you turn off the ignition, there is a time delay in the actual power down of the ECM. During that time, the ECM retracts the AIC's plunger, setting up the "high" idle for the next start sequence. Possibly you could disconnect the AIC's harness after shutting down, then restart to see if the idle will stay up. It may be possible that a temp sensor, either the engine coolant or manifold air temp are telling the ECM the engine is hot. This may drive the idle to minimum. Also, since it's a stroker, you may have other issues with regard to the engines fuel/air needs that the ECM is not programed to accommodate. You may need bigger injectors and possibly a correction to the MAP signal. I'm just guessing based on my general understanding of computer controlled fuel injected engines. Since you have owned this Jeep/stroker, is this a new problem, or did it start with the installation of the stroker? Hopefully other "stroker" folks will jump in hear regarding stroker peculiarities. If I stroked my Chevy engine, I'd have to reprogram the ECM.

bubba,
thanks for the clairification on the "scan tool" sounds like i have one, it's called a fluke.
i have 24# injectors and made a adjustible map sensor box, although it doesn't seem to do much. i have verified that it is working correctly and it will effect the engine under extreem swings in voltage, but it does'nt make it idle any faster.
i did the IAC test, something i had'nt thought of before, and it will stay at a smooth 2000rpm.
i will say that it started with the build of the strocker, i could'nt kill it before.
i did do something different in that this is a HO motor, complete with manifold and TB, (i made an adaptor for the TPS) and kept all the renix sensors.
i have built a few strocker motors for other people, with wranglers or HO XJ's, and they have turned out fine.
other than this the bitch is rude. it will white smoke 33" swampers without breaking a sweat, but this little annoyance is going to make me get a later model XJ and swap everything over.
thanks for the great input.
toad