Adjusting the Throttle on a 1988 YJ

[Ed_Lorentz]

Anyone know how to do this? the manual I have says its controlled by the computer, but I have no idea how to mess with this stuff or if this is even true. Vince and John looked at it but we couldn't figure it out....:117: Suggestions ??:question:

[Deadman 94 xj]

Why are you attempting to adjust the throttle?

[limegreentj]

you cant, its computer controlled...you'll probably need a programmer.

[Ed_Lorentz]

I meant idle.....Where do I find a programmer??? Does this require a mechanic?

[limegreentj]

you can buy them from different places, plug it into the computer and program the computer...they are expensive...you might find a buddy that has one though. whats wrong with the idle?? too fast? too slow? its probably the idle air control.

[tanz45]

Check IAC, vac leaks, fuel pressure, etc.......

If its acting up or low.

If you want it high for crawling, us a second throttle setup.

[mxg342]

What engine do you have?

[Ed_Lorentz]

Whenever she sits still she stalls...which means stop light stop signs....you name it. It's pretty slow in my opinion but I don't know much when it come to this stuff. Does anyone on here have a programmer that they would be willing to let me use....I pay in beer....Tanz I'm new to this so you have to be a little more specific...what am I looking for?

[YJBeef]

IAC is probally clogged up......on the side of the throttle body. take some cleaner and inside the opening youll see a slit opening just under the butterfly valve when held open..........or take it off and really clean it out!

[limegreentj]

the IAC is your idle air control. that or the throttle position sensor (TPS) is most likely your problem


take it off, tear it apart and clean it real well with a sensor safe cleaner. that'll most likely fix it....if not its a sensor on the throttle body

MAF or MAP (mass air sensor)

those are the 3 main components to a throttle body setup.

[Ed_Lorentz]

Ok where are they located and how do I tune that so this doesn't happen again....Sorry but I'm really stupid when it comes to these things but I'm trying to learn.

[YJBeef]

http://www.jeepforum.com/forum/f13/how-clean-your-idle-air-control-valve-756934/

[limegreentj]

you cannot tune them...they are sensors..when they shit...you get a new one.

except the idle air control...its a valve...you can pull it out and clean it real well, and clean the rest of the throttle body.

yours being a yj, probably has a MAF (same thing as a map, they just used them on older models) i think its located in your air tube....be VERY careful not to **** it up, they are sensitive....pull it out and clean it with sensor safe carb cleaner

the point of fuel injection is to not have to TUNE anything...tuning a carb went out when fuel injection came in

[Ed_Lorentz]

Ok so the forum helped a little (thanks YJBEEF) now I just have to find mine :) told you I'm new at this. As for the sensors, where would I find those?

[Fourx4sr4me]

anyone know how to do this? The manual i have says its controlled by the computer, but i have no idea how to mess with this stuff or if this is even true. Vince and john looked at it but we couldn't figure it out....:117: Suggestions ??:question:

damn jeeps:102:

[limegreentj]

Ok so the forum helped a little (thanks YJBEEF) now I just have to find mine :) told you I'm new at this. As for the sensors, where would I find those?


i said above where the maf is

and the other ones are attached to the throttle body...if you clean your IAC and it doesnt work, i have one here (assuming you have a 6cylinder) that you can have....it should work (it was off the 95 engine i put in my tj)

[Ed_Lorentz]

Ok so how do I make sure I don't **** it up....I'm just nervous when it comes to these things....so sorry I ask a lot of questions...I really appreciate the help

[Ed_Lorentz]

damn jeeps:102:

HAHA....Your telling me John good news is I haven't had a problem with the battery connections since you and vince fixed them up. I put some Seafoam in the gas tank and it appears to have reduced the roughness. Tonight I'm putting it in the Carb and the Oil.:icon_madu:

[limegreentj]

when cleaning the MAF sensor, remove the air intake tube (yours being a yj which is OBDI its most likely inside the air intake tube, if its not, post back up and ill figure it out on mine) and spray good sensor safe cleaner all over it...dont touch it with your fingers...the oil on your hands will **** it up. if you have to touch it or take it out of the tube wear latex gloves.

[Ed_Lorentz]

Guess I'm stoping at rite aid on the way home for some latex :) I'll try to find it. If I can't find it this weekend I'll post a pic of the engine so you can try to help.

[limegreentj]

if its not in the intake tube its a small black box on the side of the throttle body (i just looked on mine) the box is like 1"x2"

[limegreentj]

http://cache.autoanything.com/images/products/med/air_intake_systems/jet_mass_air_sensor_ford.jpg

that is on a ford...but looks the same...

easy way to find it in the intake tube is look for a wire with a plug going into the intake tube...if you dont see that, look for the black box...hope i helped!

[Ed_Lorentz]

Your more than helpful....I'm just a visual guy...and when we start talking about sensors and IACs...I have no idea what your talking about...if you say black box...I'm pretty sure I can find it :) Just treat me like a 2 year old :) I learn better that way....babysteps

[mxg342]

I Didn't see what engine you have. If it's a stock 1988 6 cylinder it's probably a carburated 258. Search google for Carter BBD and you'll get a lot of info on it.

The carb'd engine isn't going to have IAC or MAP sensors.

[Ed_Lorentz]

I have the 1988 4 cyl.

[limegreentj]

hmmmm! now you throw me for a loop! its probably carbed...if thats the case, take it off, clean the **** out of it, put it back on...see how she runs...and there is an idle adjust screw on the side of the carb. turn that a little bit, and pull the cable to rev it up a bit. see how it runs...too fast, go the other way, rev, too slow, go the other way, rev....trial and error pretty much...the idle screw most likely just needs adjusted and it needs a good cleaning.

[YJBeef]

thought the 4 popper had tbi then?

[limegreentj]

LOL! i have no idea...im just going off what i know about both setups...the only way to know what he has is if he looks...does it look like a carb, or does it look like a throttle body (i.e. wires going to it?)

[Ed_Lorentz]

I believe when John and Vince looked at it we were pretty sure it was a carb but I don't think we could find the screw your talking about.

[limegreentj]

bring it over here and ill see if i can get it. i wont be home tomorrow, should be home saturday until around 3-4

[Ed_Lorentz]

Alright...I'll have to talk to the wife first. I think she had plans for me on Saturday, but maybe I can get that all done in the morning so that I can get there for 3-4. Can you PM me with the address.

[limegreentj]

you can stop out tonight if you want...ill be here til around 9..then im done for the night.

[toocheaptosmoke]

It's not carbed, it is TBI. It was acting like a carb flooding the engine when it was dieing though. Did you ever throw on a new cap and rotor?

[tjblair]

It's a throtle body injected 2.5 4 cyl. I'm not sure but I thought that they used map sensors ( manifold absolute pressure )
I would check for a vacume leak. The best way to do this is with a propane torch. Take the torch DO NOT light it! Turn on the propane and blow the propane around all the vacume lines and around the intake manifold. If there is a leak the engine will stumble/ die, or rev when it sucks in the propane. You should be able to narrow down the leak pretty well ( if indeed there is one).

[Ed_Lorentz]

It's not carbed, it is TBI. It was acting like a carb flooding the engine when it was dieing though. Did you ever throw on a new cap and rotor?


Have not had a chance to toss a new cap and rotor on yet....I was thinking about swinging by Advance tomorrow and picking those up. I did however get a chance to toss some Seafoam into the gas tank, oil, and intake...The smoke storm was enormous :) but it runs pretty clean now...I wish I took pics but it was dark out and I was in a hurry

Unfortunately after I ran the Seafoam the car refuses to now hold any idle at all. The second I lift my foot off the gas the RPMs plummet ending in a stall. The heep will then fire right back up, but will stall the second I take my foot off the gas. Any ideas if this is the VAC leak mentioned by Jeff, or a sensor issue.

Is running propane around the engine really safe for an amateur mechanic. I'm just really scared about ignition and explosion here. Any ideas :074:

[tjblair]

You will be fine. just do it outside.

[limegreentj]

its not enough propane to make a huge explosion...just a poof of fire...aint no thang...lol

dont be scared, thats when bad shit happens.

[Sycotik Skier]

that sounds a lot like a vacuum leak. Instead of using propane you can use starting fluid or carb and choke fluid. I'll be at advance tomorrow night, if you stop in I'll take a look at your jeep.

[tjblair]

I agree that it sounds like a vac leak, If I had to guess I would say it might be a leaking intake manifold.
Starting fluid is a sure way for a noob to light the engine on fire.

[Ed_Lorentz]

Alright Brent. I'll stop up....Sorry guys I'm willing to try most anything but the propane thing just scares the hell out of me. I already don't have much hair...I'd like to keep my eyebrows :) Not so much the propane that scares me just the fire :)

[tjblair]

The propane will not start a fireball. there just is not enough propane,and there is to much air. its like trying to light a propane torch with a lighter a foot in front of the torch. And you don't have open spark under the hood. If you want I will check it for you, but you would have to stop by my house with a torch (I don't think I have one here)

[Ed_Lorentz]

Alright...so I think I'm going to stop by Advance tonight and let Brent try to start her on fire....then if that doesn't work I'll stop by your house with a Torch Jeff..the only reason I'm doing that is because I have to stop by Advance anyways to pick up some stuff tonight...Jeff when would you be available.


Any ideas as to how much this is going to cost me to fix ( VAC LEAK, Intake Manifold)

[Fourx4sr4me]

4,000,000 dollars seems to be the going rate around here:043:

[Ed_Lorentz]

Only if Jeff does it (JOKING).....I bet you I can get it done for 3.9 mil if you just do it yourself....

[Ed_Lorentz]

Hey Jeff...would the little plumbing type torch work :) or are we looking for something specific.

[Fourx4sr4me]

That will work

[Ed_Lorentz]

Sweet....thanks..any idea on the real cost of these repairs?

[mxg342]

Depending on what you find, it should be less than a c note.

[Ed_Lorentz]

Sweet deal...I can handle a $100...Are these things hard to fix on your own?

[Ed_Lorentz]

Alright...so I stopped by Advance last night and found one dry rotted vacuum tube...so there are probably more. I really don't feel like replacing every tube if I don't have to...Jeff is the offer still good to find those leaks for me :) I'll bring the torch that I have which should be fine. Just let me know when you can do it...and we'll get together.....

[tjblair]

Yah, Did you replace the one you found? and did it make a differance?
I'll be around tomorow if that works for you. I can't spend all day on it. But I can give it a quick look. and show you how to do the propane trick.

[Ed_Lorentz]

We did replace the one that we found...unfortunately it did not have the result I was expecting...I also cannot find time where we could get together tomorrow. Would you have some time during the week or next weekend when you could look at it.

The wife has plans for me tomorrow or else I would be there in a heartbeat.

Ed

[tjblair]

shoot for next weekend then. I'll be around sat and sun.

[Ed_Lorentz]

Works for me...I hit you up later in the week