cant figgure it out. please help.

[poweranger84]

86 ranger 2.9 5 speed.

idle really rough, unplug a vacuum line on the throttle body and it idles a little better.
it sucks in excessive air into the idle air valve even after replacing.
run way rich, cant find any vacuum leaks.

if anyone can help me out let me know.

(i have no way of pulling code)

 

[DisturbedMXer8]

86 ranger 2.9 5 speed.

idle really rough, unplug a vacuum line on the throttle body and it idles a little better.
it sucks in excessive air into the idle air valve even after replacing.
run way rich, cant find any vacuum leaks.

if anyone can help me out let me know.

(i have no way of pulling code)

Check your fuel pressure regulator. While it's idling, unplug the vacuum line attached to the back of the regulator from your intake manifold. You should have a pretty good increase in RPM. If not, and/or if you see fuel coming out of it, it's ruptured and you need a new one. If it's bad, it will cause a VERY rough idle, and extremely rich misfires in all cylinders. Definitely #1 on your checklist, in my opinion.

 

[loneranger48]

x2

 

[poweranger84]

the fuel regulator is new. but i still tryed it and it didnt change the idle

 

[poweranger84]

anyone know where i could find out where all the grounds are on the motor?

 

[holyford86]

the main one is on the side of the block below the passenger side exhaust manifold, If it's original trace it back to the frame where the funky factory clamp is, they like to rot out there and fall apart. There should be another one to the back of the passenger side head, It grounds the o2 sensor and it will run rich if this wire is messed up.

 

[RumpRangerSTX]

the main one is on the side of the block below the passenger side exhaust manifold, If it's original trace it back to the frame where the funky factory clamp is, they like to rot out there and fall apart. There should be another one to the back of the passenger side head, It grounds the o2 sensor and it will run rich if this wire is messed up.

thank u that helps me out

 

[adsm08]

While you are goofing around in there with the grounds, take that battery cable bolted to the block and bolt it to the frame. gets its away from the exhaust, make it easier to put back on if you ever have to replace it, still runs just as good.

Also, a vac leak will cause a high, lean idle. Not rough and rich.

 

[poweranger84]

alright, ill try those when i get back to nc. stuck at the parents house for the holidays....

 

[holyford86]

While you are goofing around in there with the grounds, take that battery cable bolted to the block and bolt it to the frame. gets its away from the exhaust, make it easier to put back on if you ever have to replace it, still runs just as good.

Also, a vac leak will cause a high, lean idle. Not rough and rich.

Moving the engine ground to the frame is a bad idea, the engine is not very well grounded being it sits in rubber mounts. Relocating the ground to a better spot on the engine isn't a bad idea though, in it's factory location the ground is sufficiently far away from the heat of the exhaust it's just a pain to get to.
With a speed density setup a vacuum leak could cause a rich condition simply because a map sensor monitors the engine vacuum and infers engine load from that and a couple of other things to meter fuel. If it sees lower manifold vacuum it's going to think that you are into the throttle a bit and add some more fuel.