New Member with Idle Question

[1badbaker]

Just wanted to start out by saying hello. I've been checking out the forum for a couple weeks now and it looks like there's a lot of good information around here. Now to the question...

I have a 93 Bronco XLT, I bought it about 5 years ago and have never had any major problems. For the past month or so, I've been having a rough, loping idle. It's bad enough that I can't start the truck and just let it idle without it killing itself. If I sit on the gas and keep it around 800-1000RPM it will still lope, but won't die. So, I'm wearing the hell out of my brakes, driving with two feet so I don't die at stops.

I put on a new alternator a few months ago, new fuel pressure regulator, fuel filter, serp. belt, PCV valve, and tensioner pulley within the past couple of months also. The plugs and wires are about two years old. I think it's the EGR valve or the vacuum lines. Has anyone had this problem? Any suggestions or ideas are appreciated, I'm about to lose my mind with this thing.

edit: almost forget, I have the 5.8L 351

[cajunland]

Check your iac. its usually (not always) a good place to start with idling problems, also check to see if you have any codes. itll show up if is the egr or something related and point you in the right direction

[offroadbronco]

First pull the codes and stop throwing parts at it. Your CEL does not have to be on, there can be codes w/o a CEL. Most likely you fried your TPS (throttle position sensor) or your IAC (idle air control) is dirty and needs to be cleaned.

Advance Auto or Autozone will pull your codes for free, or you can do it yourself with a paperclip and counting a blinking light. You can also buy an OBDI reader....they are usually $30 bucks or so.

[UTfball68]

I had a problem like this with my 87 with a 302...My idle was rough...so I'd adjust the idle...worked for a little while. Then I had to two foot drive because it would surge at idle and then back off and die. Mine was simply an oxygen sensor. Maybe that's all you'll need.