Yj wont idle

[graves14]

Looking for some help on this one guys cause i have no idea....

1990 yj 50k miles and a bone stock 4.2L.  It wont even think about idling.  Starts up fine and drives fine once im going but in order to keep it running at say a stop light i have to hold my foot on teh accelerator and keep it at about 1000 RPM.  Has anyone else experienced this or have any idea where the problem might be?  It can be a nusance especially in parking lots and such not to mention that its not helping my gas milage.

thanks a lot,
PK

 

[re-run]

Hey pat, when did you get a yj?????
Oh yeah your problem, i should offer some help huh?? My old cj did that all the time with the stock carb, it was a cracked vacume line like Detours said, you can play with the adjuster screws for a temporary fix but that wont last long. Your best bet is the webber, I loved mine, it is still a carb so it can get funny on hills but I think we all know a custom fab shop that makes an easy fix for that, if you do go webber, go to detours and get the plate. that is one mod I wish I had done to the cj.

 

[graves14]

im going to bring it to someone to have it looked at i dont know jack about carbs and theres a lot of freaking vaccuum lines running into that thing but for the time being where's the idle adjustment screw?  Even if its idling at 1100 rpm at least itll be better than now.  thanks

 

[re-run]

check your timing too, I droped my battery into the distributor once and it screwed up my idle

 

[JeepinMaxx]

Pat, I have a stock '90 carb in the shed - you can have it if you want to check things out.  I'll be around this weekend. 
Check out the Weber/HEI set-up.  I sold my Weber/HEI set-up to CJRon - maybe he still has it :wink:  PM him

If you want info on early YJ upgrades - give me a call on my cell
Frank 860-558-9754

 

[jon]

Been there done that.  in order:

1)  Check for vaccum leaks. I prefer spryaing carb cleaner as shooting ether around my engine compartment scares me.

2)  Do a nutter bypass on the setup.  Once the engine gets hot the computer trys to adjust the carb and timing. doesn't work well once the carb gets older.  http://www.4x4wire.com/jeep/tech/electrical/jn-ignition99/

3) swap the carb.  Webers are nice but $$$  I put a MC2100 on mine.  Nice swap, worked really well.  My buddy is running the same carb on his 360 and it will keep running whne the jeep is on its side or sitting on the rear tire carrier.  Or even upsidedown (if you were at the DWE truckshow last year you saw it.)  HEI is also a good swap but $$$.  I would reccomend the TFI swap. http://keith.cj8.tripod.com/tfi_upgrade.htm  muh cheaper, and almost as good.

4) Ditch the 258.  I contemplated the mopar MPI kit or hacking together my own.  But I would be throwing 800- 2000  at a motor and still have a older top and bottom end.  I picked up a 4.0 HO with 70k for $200.  after a littel stress, I got it running and its got nut.

5) next step.  either stroke the 4.0 for s&g's (pump gas viable), stoke the bejesus out of it and run propane, or just throw a 350 or 4.3 in there.

 

[re-run]

Wow someone has played this game before, I went through it with the old CJ and my best advice is dont go to detours asking for suggestions, I did and I ended up selling the CJ  and spending almost 5k on my YJ.

Thanks Mark :mad02: