Renix fuel system.

[Wounded_Fighter]

Is there a way to adjust the amount of fuel coming from the injectors? Like a way to shorten the burst of fuel?

[JMO413]

No it's all controlled by the ecm

[cruiser54]

What is your goal? 

[Wounded_Fighter]

Lower the amount used.

[fiatslug87]

39 minutes ago, Wounded_Fighter said:

Lower the amount used.

That's done with your right foot. 

[Jeep Driver]

56 minutes ago, Wounded_Fighter said:

Lower the amount used.

Do you have an AF meter?

[WyoCherokee]

You can grab an adjustable Fuel Pressure Regulator. However, we must ask. What is your goal, symptoms, problem? If you are running rich, there are other items that will cause a rich condition in a Renix. 

[Wounded_Fighter]

Goal is mpg.

Logical thought was air/fuel mixture, add more air?

 

So I threw more air into the system (bored throttlebody) she likes it, a lot, idles now at 1300ish? (No actual tachometer on truck) searched forum, found a few high idle topics. Grounds checked, c101 deleted already in past. Only difference for high (warm) idle is the throttlebody, ran normal before it. Still investigating and theorizing. I need to buy a REM too.

 

 

[Wounded_Fighter]

1 hour ago, fiatslug87 said:

That's done with your right foot. 

But my right foot loves the floor. 

[Ωhm]

More air, more fuel. O2S will always attempt to maintain a 14.7:1 air/fuel ratio, within its range of authority, otherwise ECU goes into open loop. High idle is vacuum leak or TPS adjustment.

[omega_rugal]

on a 4.0? sorry they are gas guzzlers

 

go propane like i did...

[Eagle]

Adjustable MAP sensor.

[Wounded_Fighter]

11 hours ago, Jeep Driver said:

Do you have an AF meter?

AF meter? Probably not.

 

52 minutes ago, omega_rugal said:

on a 4.0? sorry they are gas guzzlers

 

go propane like i did...

Yes,... propane? How do you measure mpg or rather mpt (tank)? Worth it?

 

@cruiser54I'm not sure how adjustments are made on the tps? Do I just wiggle it around and screw it in and pray, if it's off do it again?

 

Edit, while measuring with the probes.

[omega_rugal]

my MJ on propane gives round 20-22 mpg on the highway, some less in the city, but propane is 40% cheaper, so you must take that into account

 

the 4.0 is rated at 17 mpg when running on gasoline so i´m not doing bad

 

you also save a lot in oil changes, i have not changed the oil in 2 f***ing years and still looks clean, i´m changing it the next weekend because the additives are probably long gone but 2 years? that´s like 5 or 6 oil changes if it was running on gas, all that money can go into propane instead...

 

of course some sacrifices should be made, i´m running on the lean side most of the time, running at no more 2000 rpms, after that it starts losing power, but when it comes to torque i didn´t notice any change, even fully loaded it doesn´t sweat as long as i keep it in the 1600-1800 rpm range

 

unless you install and tweak your lpg system yourself you´ll end up spending more, most lpg mechanics give the engine too much propane to mimic the response as if was running on gas

[13 Legion]

8 hours ago, omega_rugal said:

 

you also save a lot in oil changes, i have not changed the oil in 2 f***ing years and still looks clean, i´m changing it the next weekend because the additives are probably long gone but 

I’m not following how running on propane means you have to change your oil less? There is still wear and tear( friction) happening while you are driving. I realize some oils are advertised as better or there are synthetics....am I missing something here?

[Jeep Driver]

11 minutes ago, 13 Legion said:

I’m not following how running on propane means you have to change your oil less? There is still wear and tear( friction) happening while you are driving. I realize some oils are advertised as better or there are synthetics....am I missing something here?

Propane is a cleaner burn, less cylinder wash or fuel wash. 

 

Blowby allows unburned gasoline to inter the crankcase and contaminate the oil over time. 

 

 

No, not a fan of propane but whatever.....

[cruiser54]

Propane enters the engine as a vapor, not a liquid. 

[cruiser54]

12 hours ago, Eagle said:

Adjustable MAP sensor.

This. And then you can lean burn your engine, get a new one, and not have saved a dime. 

[omega_rugal]

10 hours ago, 13 Legion said:

I’m not following how running on propane means you have to change your oil less? There is still wear and tear( friction) happening while you are driving. I realize some oils are advertised as better or there are synthetics....am I missing something here?

 

gasoline burns dirty, leavesa alot of carbon residue and acids... my old ZJ turned the oil into tar in less than a week after everychange...

 

i[ll show the oil when i[m doen changin it

[Wounded_Fighter]

Current idle when warm.. approx 10mins of driving.

 

 

[Ωhm]

Sound too high.

[Ωhm]

Check Throttle Body Butterfly Adjustment using Cruiser tip #14.

http://cruiser54.com/

[benjy_26]

Don't Jeep 6's run lean enough to eventually crack the exhaust manifolds? 

[Ωhm]

8 hours ago, benjy_26 said:

Don't Jeep 6's run lean enough to eventually crack the exhaust manifolds?

 

Not in a Closed Loop condition. If vehicle ECU goes Open Loop, no one knows then (Rich or Lean).

[Wounded_Fighter]

So, I adjusted the idle air bleed screw...... (dumb me didn't know that was a thing)

So far sitting in the driveway it sounds a lot better. And since I replaced the guage cluster and now have a tachometer! I can say prior it was idling arou d 1300rpm. Now its 700-900rpm in driveway. Once it goes down the road a bit it sits happy at 1k. 

 

Have to take it down some high speed still to see if I run that hesitation idle bit again like it was in the video.