The Oreo (T.J.'s YJ)

Finally got to really test out the clearance I gained from cutting the rear wheel wells and installing the TJ flares. Same rock, same flex, same tires, a little less mud. I'd say they made quite the difference.

Before:



After:



I'm actually so impressed by the outcome that I think I'm going to do the same to the fronts, because even before full stuff up front this is what things looked like yesterday:



Regardless, I am pleased. Up next is getting in touch with Elias out in Townsend to replace my completely wasted steering column bearing, and possibly a few other things I need taken care of but don't have the means to do myself. Unfortunately I think the inverter project is going to be put off for awhile though. I'm still probably going to order the majority of the components and be ready to get it done when I find some time, whenever that may be.

The flares look good, The stock flares are kinda lame looking.
Replacing the steering column bearings is not hard to do on a YJ.
Seems to me, that with all you have done yourself you can do that too.
I guess you would have to get a price from ELIAS first but I would assume that it's less expensive to do it yourself, plus you will know much more about what makes your jeep tick.

https://www.google.com/search?q=yj+steering+column+bearing&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Finally got a break weather-wise to get some stuff done. I've had a new distributor cap, rotor, plugs, and wires sitting around for months now that I've been waiting to get on. I fooked up a bit and ordered custom-make MSD wires, so the whole process took way longer than it should have (and required purchasing a cheapo Harbor Freight table vice), but I can definitely feel the difference. All that stuff was overdue for replacement.



At the same time, in hopes of fixing my lack of high idle on start-up, I left the battery unplugged over night to try and clear the ECM like I've read up on various forums. I also tried the steps I found on Quadratec's website for resetting the ECM, but honestly I have no idea if it worked or not. The Jeep still doesn't high idle from a cold start, however my rough idle issues seems to have been solved with the cap/plugs/wires upgrades (and maybe the ECM reset if it worked?) Instead of being down around 500 it pretty much stays steady at 600-650 now, which to the best of my knowledge is where it should have been all along. It feels much stronger and is much more responsive now, but that's to be expected after this sort of work.

Can you guys chime in and tell me what your Jeep usually idles at at start up? My recollection is that my Jeep used to jump to around 1500-1700 on cold start-up and eventually make its way down to around 1000, and then settle around 650-700 once it was pretty much up to temp. Now, it only jumps to maybe 1300 on cold start-up and only stays there for maybe a second or two before dropping down to 1000, and then will drop down to 650 once it starts warming up.

Could a bad temperature sensor or bad coolant temperature sensor (always forget if they're the same thing or not) cause something like this? I had the sensor replaced sometime last year (I forget why at this point) and really since then my temp gauge has been acting strange, and by that I mean it gets up to 180* and then immediately drops down to 150*, then climbs back up to 180* then immediately drops off again down to 150*. If the sensor made the ECM think the Jeep was warmer than it actually is on start-up, could that cause the Jeep to keep the revs down (because it doesn't think it needs to high idle)? That sounds plausible to me, but I have no idea if that's how things work, and hopefully one of you does.

(Also as a heads up, I have changed the MAP sensor and TPS, and also cleaned the throttle body with no noticeable change in idle at all, so that hopefully rules those things out.)

I'll have to double-check next time I start up the YJ, but that sounds correct to me.

It definitely revs high, like 1500 or so?, for the first 5 or 6 seconds, then drops a bit, then smooths out at like 700 after it's warmed up for 30 seconds or so.

Also in terms of the thermostat, yes, it's appropriate to hit a temp and then drop, climb back up and then drop. Although mine typically goes between like 210* and 180*. Whatever is directly in the middle on the dash is probably correct for the high temp.

But yeah, the YJs are kind of dumb in that there's a coolant temperature sensor which feeds the ECM information and then a temperature sensor that feeds the gauge. Someone correct me if I'm wrong, but I think the one in the front of the engine near the t-stat controls the ECM and the one in the back controls the meter on the dash.

I'll take a video of my YJ starting up sometime. You might be able to youtube it too for further double-checking.

Yeah mine used to high idle at that level, but for some reason something changed one day and it just hasn't been the same. I made sure to keep an eye on it this morning when I started it, and it revved up to no higher than 1300, stayed there for about 5 or 6 seconds (which is a bit of a breakthrough compared to what it had been doing previously), then dropped to 900-1000 and idled there until I had to take off for work (only got to about 120* before I left).

The good news is it is definitely idling far closer to 650 (once at operating temp) than it has been in a long while, and on start-up it doesn't sound or feel like the thing would rather stick a gun in its mouth than run another second, so the high performance wires and upgraded cap/rotor/plugs have definitely made a difference (purchases justified). The plugs are now also gapped a little above spec because of an article I read in Jp Magazine (it called for .065, but that seemed like a little much so we went with .044) to help the little 2.5 burn better.

I do want to note though, when it drops from ~1300 to ~1000 on initial start-up, that drop isn't slow and gradual, it's an all-at-once noticeable in sound and feel sort of drop. The drop from 1000 to ~650 is nice and gradual, and I just know something somewhere is throwing the high idle off, but I just don't know what. It doesn't throw any engine codes and hasn't in a long time, so it's primitive brain is no help in telling me what the issue is, so I'm left to my own trial and error at this point. All of the vacuum lines are solid (in function not necessarily in looks), and a few were replaced a few years back because they were pretty rough so I'm left to believe it's not them either.

Who knows, maybe the brain is cooked and there's no solution; that wouldn't be out of the realm of my sort of luck. The battle of man versus machine continues.

Sounds normal, you do NOT, want it to run on high idle for any extended length of time, if at all possible, (wasting fuel and causing wear and tear)
The sooner the high idle goes down to Curb idle the better, the thermostat has nothing to do with each initial cold start!
or the idle.
It is the job of the IAC, CTS,tps, O2'S AND ECU.

Plug wires and plugs are there to do only one thing,(get a crisp spark in the combustion chamber) so changing them and it running better simply says that your plugs and wires were NG.
It doesn't matter what brand wires you have as you will not notice the difference between new cheap wires and new expensive ones as long as they do not leak electricity or have too much resistance.
Spark plug gap being too large or too small will cause lack of power, and incomplete combustion and will affect performance.(Lots of experience with automotive and Harley engines as far as spark plug gap and fuel delivery goes),, .

If the jeep calls for .035 spark plug gap or what ever it calls for,, then put it at that, you are wasting your time setting things to the wrong specs and wondering what the issue is with something else,, as it was designed to basically run on 87 octane PISS and a spark.
It is designed to run best with simple  $1.99 copper core champion spark plugs,, not platinum!!
You should be able to start it and drive it away instantly without a hiccup at all what so ever..
Waiting for it to warm up is not necessary.
Your lawn mower is as dumb as they come and you probably don't warm it up before using it,, and it works fine i'll bet.
You just can't get a dog sled to go like a rocket no matter what you do to it!

Yeah the plugs and wires were toast, so it was good to finally change them out after five years of everyday driving. I didn't do crazy fancy plugs, just the Champion ones like you mentioned Mark.

Correct me if I'm wrong though, high idle on cold starts (on any vehicle not just a Jeep) is to help warm the motor up faster. Now obviously it shouldn't last minutes at a time, but what Geoff described seems pretty on par with my experiences in other vehicles and previously the Jeep. My biggest issue is this: the Jeep takes forever to come up to temp. Granted, it was extremely cold for extremely long stretches this winter, but I still don't think it should take a four cylinder anything 10+ minutes to reach maybe 125*. Maybe the temperature sending unit is in fact no good, and the temperature is higher than I'm seeing on the dash. That could certainly be the case, and could explain why it seems like it's taking forever to come up to temp.

That being said, it's always needed time to warm up, and I've always obliged and given it that time, but this winter was exceptionally bad and my gas mileage dropped easily 3-4 mpg over what it was back in the summer last year. I know some of that can be attributed to winter blend, but I refuse to believe all of it is gas-related. To boot, I barely used 4WD all winter, so I'm willing to rule that out as a culprit also (kudos to the Grabber AT2s I've got on there). I've changed the TPS, MAP sensor, O2, sensor, and did a full cleaning of the throttle body and IAC valve all in the last year in hopes that they would cure things (and because things needed to be replaced), and it's made no difference in the idle.

I think this idle thing is/was affecting my mileage because of the length of time needed for warming up, and because when it was idling around 500 all the time it took a fair amount of throttle to get it moving. Add in 31s with 4.10s behind the 2.5 and it's a recipe for hating your life. I obviously don't drive the thing for its fuel efficiency, but putting in 8 gallons of gas and going 110-120 miles isn't my idea of a solid investment. And keep in mind I was getting 17-19 mpg this past summer under these same parameters, so something about the cold and the Jeep just don't mix. Hell I drove the thing 500 miles to D.C. in 95* weather and got over 20 mpg, granted that was all highway.

Anyway, moral of the story is this has been bothering me for awhile and I'm looking for ideas on where to start. When I ran out to grab lunch a little while ago it did start and rev up to around 1500 and float there for 2-3 seconds before dropping down to 1000, so I'm starting to think progress has been made. As I said before, it's running much stronger and is a lot more responsive, and the idle isn't nearly as erratic as it's been in the past. The only thing I haven't replaced that could be messing things up (in my mind) is the IAC valve, but again it's not throwing a code for it so I'd hate to drop the money on something that accomplishes nothing. Once the weather warms up I'll see what happens to my gas mileage and take things from there. I've got a million other things to address on the thing so what's one more.

I think that you had a skip, that would cause low idle, low power and more throttle needed to make it move.
It sounds like it is working just fine now,,
High idle on a fuel injected engine is just a means of keeping/getting the engine running, it will regulate the idle very quickly.
The temp gauge is just that,, it's a gauge and doesn't know a thing it just reads temp.
You need to stop looking at it, especially when it is not up to temp which is about 195 degrees.
The only thing it's good for is telling you when it is overheating.

Older cars with carburetors needed high idle as a way to keep it running while engine is cold and having a choke helps to stop hesitation/ stumble etc.,  they are very primitive and pollute quite a bit during the choke induced warm up process,, compared to your injected engine that can make adjustments in a Milli second and can drive away immediately after starting it and runs the same every time..

I have a 4 cyl injected ford ranger that revs very high, 1500 or so, for the first 4 seconds , it sounds like it is going to blow up! then drops off quickly to 1000 then to 700 or so.
There is Curb idle (engine warmed up and at manufactures specified rpm)
High idle is a rpm range to start the engine with AND NOT FOR WARMING UP THE ANTIFREEZE,(depending on  air temp and engine sensors warm up times will vary) it wants go to CURB idle as quick as it can.

High idle is to get the cat up to temp for emissions purposes these days more so than engine temp IIRC.

The scion FRS I just had had the craziest warmup you ever heard with all kinds of overlap to get the cat to temp quickly for cold start emissions regulations. It's a braze new world indeed. I'm happy to be back to my farm tractor.

Scion's sure are different huh,,
Most Fuel injected engines don't really have a high idle specifically for emissions warm up reasons..(POLLUTION) being one of the reasons.
The days of excessive engine run time to warm up the electric choke spring are gone.

No that's exactly why it has the high idle with the insane overlap. The engineers specifically stated it was to warm up the cat for cold start emissions. It only last for about 30 seconds, but it was quite odd.

dongalonga wrote:No that's exactly why it has the high idle with the insane overlap. The engineers specifically stated it was to warm up the cat for cold start emissions. It only last for about 30 seconds, but it was quite odd.

Yup, our 2014 Mazda has a "special feature" where the initial startup idle is around 1500rpm until it's warmed up. Since there's no temp gauge on the dash, you just get a blue coolant light until it's done.

(Always screws me up when leaving the garage, though, because it makes putting it into second gear *way* faster than I expect, because it's essentially automatically pressing the accelerator)

Well my guess is the YJ is even more primitive than what you guys have described, because I only have an upstream (before the cat) O2 sensor. If the system required the cat to come up to temp I'd be totally shit out of luck because my catalytic converter doesn't exist. Lou's Custom blew the remnants of it into a cardboard box when they put a new exhaust on the thing back in 2009, so it's been straight pipe since then. It's physically there, but none of its guts are. Pretty much the one nice perk of owning a vehicle that's almost as old as you are.

This is all good info though. I do think the plugs/cap/rotor have certainly helped with the issue (a skip is a good way to put it), and it just feels a thousand times better when idling and driving around. Some mornings were real bad on start-up, to the point where I was convinced it was going to stall out even though the tach read around 800. If I had to give a visualization of the way the Jeep sounded/ran when it first started up, it would be a deaf, blind, 15 year old Chihuahua pissing itself where it sat. It was seriously that awful. No offense to any Chihuahuas who may be reading this.

Btw, have you looked up the specifics on how open/closed loops work on our vehicles?

It doesn't specifically have a Cat sensor, but it does run under open loop conditions, calculating according to both sensor input and pre-programmed behavior, for the first however long until it switches into closed loop which calculates according to both historic and current data.

http://www.thirdgen.org/open-loop-closed-loop

http://www.jeepforum.com/forum/f12/fix-old-problems-got-new-ones-1140414/#post10750258

The post above is from when I was having weird idle issues with my YJ a couple years ago.

"Feedback from the 02 or A/F sensor(s) influence short term fuel trim and then in turn short term fuel trim influences long term fuel trim.
Short term values are not stored in memory and are lost when the ignition is turned off. Long term values are stored in memory, because they are part of the basic injection duration. Long term values affect injection duration in OPEN and CLOSED loop because they are used to calculate basic injection duration
It is important to remember that ACTUAL fuel trim is opposite of the actual DTC code stored.
A system to lean with code of P0171 will mean the ecu is making a RICH correction.

FUEL TRIM:
As things change over time the ECU needs a way to adjust the injection duration and improve drivability and emmisions performance. Fuel Trim is a program in the ECU designed to compensate for these changes.
Fuel trim allows the ECU to LEARN and adjust the injection time quickly back to "NORMAL"
SHORT TERM FUEL: Instant responce and correction
SHort FT is based on the 02/-A/F sensors and therefore only functions in closed loop. SHort FT responds rapidly to changes in the O2-A/F. If Short FT is varying close to 0% little or no correction is needed. When SHORT FT is positive, the ECU has added fuel by increasing injection duration. A negative% means it is subtracting fuel by decreasing duration.
The SHORT FT value is a TEMPORARY value and not stored.
SHORT TERM FT is used to modify LONG TERM FUEL TRIM. When the SHORT FT remiains HIGHER or LOWER than expected, the ECU will add or subtract this from the LONG TERM VALUE.
SHORT TERM FT is a temporary addition or subtraction of fuel to basic injection duration


LONG TERM FUEL:
Long FT is stored in memory because it is part of the basic injection duration calculation. The ECU uses the SHORT FT to modify the LONG FT
Long FT does not react rapidly to sudden changes, it only changes when the ECU decides to use the SHORT FT value to modify it. It is run in open and closed loop and is stored in memory.
A positive % indicates the ECU is adding fuel and a negative% indicates its removing fuel.
LONG TERM FT is part of basic fuel trim and stored in memory as a guideline."

From http://www.tundrasolutions.com/forum...rk/#post417881 (Good explanation)

So because you reset the ECM you're definitely going to have to give it a couple tanks of gas before you can re-evaluate how your idle and response/gas mileage is doing.

Oh, and a couple notes:

That sudden drop is correct. That's your computer switching from open to closed loop.

Gas mileage in the winter is definitely going to be worse if you're letting it idle to warm up every time (and for longer than normal)

My 4-banger will take like 40 minutes to get to temp just idling, but will start blowing heat out of the vents by just driving to the end of the street. There's no need to let it warm up before driving, it doesn't help with engine wear or anything because modern oil has both cold and warm viscosity. You're better off just letting it run for 30 seconds or so and then taking it off so it can warm up quickly.

Have you cleaned your intake yet? Either the IAC or just the intake manifold in general? That makes a suprising world of difference with idle as well, but like I said...with an engine reset, it's going to run crappy for the first couple tanks of gas.

CrawlingForward wrote:Oh, and a couple notes:

That sudden drop is correct. That's your computer switching from open to closed loop.

Gas mileage in the winter is definitely going to be worse if you're letting it idle to warm up every time (and for longer than normal)

My 4-banger will take like 40 minutes to get to temp just idling, but will start blowing heat out of the vents by just driving to the end of the street.  There's no need to let it warm up before driving, it doesn't help with engine wear or anything because modern oil has both cold and warm viscosity.  You're better off just letting it run for 30 seconds or so and then taking it off so it can warm up quickly.

Have you cleaned your intake yet?  Either the IAC or just the intake manifold in general? That makes a suprising world of difference with idle as well, but like I said...with an engine reset, it's going to run crappy for the first couple tanks of gas.

I'll go in order:

Glad to hear the sudden drop is correct. I remember it taking a bit longer than it does now in days of old, but I guess that's neither here nor there.

I should clarify warm-up. When I say warm-up, I mean watching the temperature gauge move at least a tad above 100* (the lowest marking). I shoot for about 125* just as a reference point, because generally anything below that and the Jeep will bog down terribly on acceleration, and often the transmission won't want to shift or occasionally won't stay in gear because it's so cold (but that's only in the dead of winter though). What can I say, she's old and slow. But you're absolutely right Geoff, if I start driving it it warms up quicker. It's just that if I don't give it its time to warm up it drives like an absolute dog.

I have cleaned the throttle body and IAC valve thoroughly as of late 2013/early 2014 (can't remember the exact time I did it.) I mean completely taking the throttle body off the Jeep and scrubbing it with throttle body/carb cleaner and a toothbrush. Both the throttle body and the IAC weren't too gunked, but they were certainly shining when I was done.

Surprisingly it's not running crappy at all, which leads to believe either: a) the reset didn't work (or somehow I did something wrong), or b) it did and everything is finally working in conjunction, but the change was minor enough that I'm not noticing it. If the cookout ends up being this weekend maybe I'll talk to some people there about the way I did the reset and whether or not it was correct. I also left the battery unplugged overnight Saturday into Sunday in hopes of that clearing the memory as well (and just to be safe went through the reset procedure before plugging it back in), but again I'm not sure if any of it took effect.

One last thing I should add: the TPS ended up going bad on me around this time last year, and so I replaced it with a cheapy one from AutoZone. From things I've read online, it's entirely possible that my Jeep was idling too high on start because my old TPS was going, which could certainly be the case. It may be that the Jeep is idling correctly on start-up now as opposed to what I was used to because the TPS was no good for all those years. This scenario is certainly not out of the realm of possibility.

Have you ever changed the o2 sensor?  it could be lazy and cause the issues that you have described when the engine is cold.
You should have no problem starting it cold and then driving it away immediately, if not then a sensor could the issue.
If you do get a new o2 you should not use a Bosch, use a Denso.

Mark wrote:Have you ever changed the o2 sensor?  it could be lazy and cause the issues that you have described when the engine is cold.

I have. It was done last summer in hopes of fixing the idling issue (and it may have thrown a code if I remember correctly), but obviously it didn't make any difference in the idle. I didn't replace it myself so I'm not sure what brand was used, but I can take a look and see if I can find any manufacturers' marking on it the next time I'm under there.

Make sure you have a quality o2. A cheap o2 is just as bad as a broken one.

Well the IRS fairy was kind to me this year, so of course I was kind to the Jeep. Just pulled the trigger on some Riddler diff covers for the D30 and the D35, as well as an MV-50 12-volt air compressor and a Bestop cab cover (for those rare occasions the hard top comes off). Next weekend I'll be heading to Crown Auto to pick up some of their 4340 chromoly D35 axle shafts and some TJ front flares. I've officially decided to join in on the Rausch Creek trip in July and all these things should help me make it back in one piece.

My plan is to do the axle shafts and the diff covers together, problem is I have no experience swapping out axle shafts. I've watched a few videos on how to do it on the D35, but videos don't show everything. Anybody done this and have any advice? I have a good idea on what it's gonna take but any tips or tricks would be appreciated.

its pretty simple
1:take off wheels
2: take off brake hardware
3: take off diff cover drain and spray down with brake cleaner
4: remove cross pin retaining bolt and slide out cross pin
5: push one axle shaft in from hub and with a small screwdriver remove c clip and axle will slide out. repeat on other side
let me know if you need anything more specific its really simple don't psych yourself out

Purchase a new cross pin retaining bolt along with axle bearings and new seals.

nnovickzj wrote:its pretty simple
1:take off wheels
2: take off brake hardware
3: take off diff cover drain and spray down with brake cleaner
4: remove cross pin retaining bolt and slide out cross pin
5: push one axle shaft in from hub and with a small screwdriver remove c clip and axle will slide out. repeat on other side
let me know if you need anything more specific its really simple don't psych yourself out

Sounds pretty much just like the videos I've watched. I saw in one of the videos that it's best to remove the retaining straps (?) or whatever they are in the housing to make it easier to get at the cross pin retaining bolt. I'm not sure what they are, but here's a photo of what I'm referring to. It's what the air ratchet is loosening.



Is there any reason I should get a new retaining bolt Mark? Do they strip easy or is it just one of those better safe than sorry situations? And the axle shafts come as a kit with new seals, bearings, C-clips, and tone rings, though again I'm not sure what the tone rings are for but I'll do my research on that as well.

Also does anyone have recommendations for a brand/type of gear oil I should when I refill the diffs? I'm sure my Haynes manual says what type to use but I've got no experience with changing/draining the diff so I don't know what brands to use or avoid.

The bolt has been there for many years and has done it's job, it's very inexpensive, but for piece of mind I would change the bolt if for no other reason.
The tone rings are for anti lock brakes i believe.
80/90-- 75/90 Weight is probably what it calls for, as far as brand goes i think that any new oil would be ok.
I'm pretty sure You should be able to remove cross pin blot without removing the carrier bearing strap/cap.
If i remember correctly, you can remove the bolt with a 1/4 in drive breaker bar and a 5/16 socket or whatever size it is.