low idle

[pug]

1990 2.5 ax5. When i start it up it idles normal. Then when it warms up sitting at a stop the idle drops down around 200 rpm. Any ideas thanks

[MjAllTheWay]

I have the same problem but mine idles at like 400 to 500 mine is a 88 auto 4.0 trans but i can't find the problem.

[skeletor]

I have the same problem in my 89' 4.0. starts good, rpm shoots then settles around 4-5 sometimes going up to 5-6 but the low idle always prevails. always starts, always strong.

[MjAllTheWay]

I have the same problem in my 89' 4.0. starts good, rpm shoots then settles around 4-5 sometimes going up to 5-6 but the low idle always prevails. always starts, always strong.

 

Yep mine runs good runs strong jest has a low idle.

[pug]

Does anybody know if you can adjust a tbi. I also forgot to mention it is a rough ido. thanksl

[Wildman]

If the IAC is good *and clean*

 

There is a small adjustment screw on the back of the TB throttle arm that can be adjusted for idle.

 

Seam to know someone whom used a manual TB with a AW4 swap, and had to make this adjustment :D

[pug]

Does somebody have a picture of the IAC thanks

[Wildman]

5th one down the list........

 

 

http://www.lunghd.com/Tech_Articles/Eng ... ostics.htm

[pug]

Just wondering would this cause low rpm and rough idel. thanks

[Wildman]

Generally, the IAC will cause high idle at start-up, and rough idling.

 

Also check your MAP, make sure the vacuum line is clear and connected on both ends.

 

Another possible cause is the EGR valve, I had one so bad, it would choke the engine right out, I disconnected it, and plugged the vacuum line *we don't have sniffer test here on anything before '96*

 

And.......while your at it, check ALL the vacuum lines, one loose/cracked hose could cause rough idling.

[pug]

On the vacume lines were they all go together by the valve cover. Is this something i can buy at auto part store. i don't know what it is called

[Wildman]

On the vacume lines were they all go together by the valve cover. Is this something i can buy at auto part store. i don't know what it is called

 

:hmm: :dunno:

 

You mean the tree??? Where all the lines connect???

 

I don't think a parts store would have a part like that.........JY is your only bet. You could check the "Help" section to see first :dunno:

[pug]

I will try that. I am tired of giving it gas at a stop to keep it from dying