What is the correct RPM at idle??

[Jake's Dad]

Rough Idle - What is the correct RPM at idle??

I have noticed a slight problem. When Im in drive and at a light, my engine seems to idle (maybe) to low, it goes down to about .5 rpm (500 RPM), and seems to want to stall out. It has that funny "Im stalliing" vibration. I give it a little gas on take off and it sputters, then picks up. A couple times when fully stopped, I put it in neutral and the RPM's pick up to around 1000, and it idle's great.

I have replaced the fuel filter and have new plugs and wires, too. The problem was happening before I changed out the plugs.

One of the 02 sensors is going bad, too.

Any ideas? I was thinking that it needs an idle adjustment?

What does your truck idle at when at a light??


JD

 

[DarkFox1]

you know, I have a similar symptom. It idles rough, no lights are on, and when I gas it it acts like it wants to choke off and then eventually picks itself up. Are you having overall performance problems? bad gas mileage?

I had a problem about a year or more ago wher ethe car wouldn't stay running at all until it warmed up, they said it was the PCM and it needed reflashing.

If you're not having the other symptoms I mentioned its probabablly a PCM or something similar, if it is doing that stuff.. I am having the same problem.

I idle at about 500 rpm at a stop. I really dont know if its always done this, but as of right now.. it does

 

[Jake's Dad]

Well I notice the same kind of "shuttering" when Im not giving her gas while doing 40 mph - just crusing. Same "shuttering" happens when Im at a light with it in drive that I mentioned before. Its fine when Im up at speeds of 65 or more.

I just took it to pep boys and they are going to have a diagnostic guy look at it. The guy at the counter thinks that its maybe a vacuum hose somewhere or something similar. All I know is that the starter they rebuilt for me last week still doesn't sound right.

The 02 sensor made the CEL come on, so that might be contributing to the problem.

JD

 

[snooper0069]

id check the fuel pressure . it should be between 35-45 at idle . with the engine running at idle unplug the vacuum line on the fuel pressure regulator , if this regulator is good the engine should immediatly speed up considerably.
this is what was wrong with mine just recently

hope it helps

 

[Alec]

you could always try resetting the computer. can't hurt.

 

[Jake's Dad]

Yeah, I pulled the negative battery cable off when I put my KKM filter in for about 40 minutes.

JD

 

[jjue]

The idle should be between 700-800 RPM. Mine is normally 756 RPM although some Mustang books say 728, or.... You know what, I forgot what they say, but between 700 & 800 is normal. My IAC caused mine to drop to 500 since is was getting stuck partially closed.

 

[Jake's Dad]

I have an IAC on order. Should be easy to install (?) seeing that it is very easy to get to. Looks like 2 bolts and its off -

JD