need some help plzzz

welderman78 · #1 12-27-2011, 06:04 PM

Hello all i have a 1999 3.0 flex fuel 4wd that idles rough

. i have change the plugs, wires, coil pack, injector #4 and the acclerator switch and the idle control value new air filter and cleand MAF and stills runs rough after it worms up but runs great just idles rough in park. thanks for your time and help

MUDFLAP · #2 12-27-2011, 06:07 PM

Kindah the nature of the beast. How bad is the idle? Last oil change?

webster426 · #3 12-27-2011, 06:17 PM

Run some Seafoam through her......that has helped me in that past.

welderman78 · #4 12-27-2011, 06:29 PM

3000 miles ago and i will try some sea-foam or how about some Lucas fuel treatment

bassplyer92517 · #5 12-27-2011, 07:04 PM

Unfortunately you'll just be throwing parts at the problem if the truck doesn't throw a code or you don't have any way to narrow down your search. You're off to a good start though, just go through all the basic maintenance stuff because it can't hurt anyways if you have the money. As said before, sea-foam works wonders and lucas fuel treatment can't hurt. I'm curious though as to why you replaced injector #4, seems pretty specific? Did you have a problem with it or something? Possibly related to rough idle?

welderman78 · #6 12-27-2011, 07:59 PM

yes it all started with cracked plug wires so i changed them first then was running rough on take off but no codes so had mid-way ford look at it and they found injector 4 was bad so i had it changed.then it through a code for the MAF so i cleaned it and then it through one for the O2 senors changed them and was doing great and now it is idleing rough but runs great past 1500 rpm.so i have been doing some looking around and seen that the IAC or idle control value was the problem so i cleaned it first and nothing so i changed it and it made it worse so i put the old one back on and still the same so i guess i am waiting for another code or something else to go wrong. thanks for you help.

bassplyer92517 · #7 12-27-2011, 08:30 PM

Was the rough idle there before you had the cracked wires? Or did it just appear one day and you noticed the wires?

bassplyer92517 · #8 12-27-2011, 09:13 PM

Honestly there have been so many changes recently its going to be really hard to isolate what could be causing it, I'd say your best bet is to run your truck through a couple driving cycles so your computer can re-evaluate everything that has been done to it. You said you replaced all the O2 sensors? It takes about 3 drive cycles for the computer to even adjust the air/fuel ratio during start up. I don't know how recent these things were done, but if less than 1000 miles you should wait before you spend any more money. And in regards to the O2 sensors again, at start up will be the worst because it takes a minute for the O2 sensors to heat themselves up and be able to report back so for those first few minutes your computer is taking the air fuel ratio it knows best (the one with the old sensor) and using that while warming up, causing a rough idle.

welderman78 · #9 12-27-2011, 11:13 PM

ok thanks bro

bassplyer92517 · #10 12-28-2011, 12:51 AM

Np man, good luck with it

welderman78 · #11 12-28-2011, 05:29 PM

Well the turd through another code to day a random multi misfire i think i will but a bullet in the thing any ideas. Check the spark it is good at plug and at coil pack.What a turd

bassplyer92517 · #12 12-28-2011, 07:29 PM

Well, my grandfather always taught me to look at the simple stuff first. So go ahead and check your fuse box in the engine compartment, pull out the fuse for Powertrain Control Module. If this fuse is blown it could possibly explain what is happening, although i would've expected more drastic results, but it can't hurt to check. Here is a link to your fuse box diagram:
http://www.scribd.com/doc/18074679/1999-Ford-Ranger-Owners-Manual
Pg.138-139 shows the PCM.
After spending $300 on a problem in my friend's Audi it ended up being a blown fuse, lol. Can't hurt to check.

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After that though it could be a vacuum leak, bad EGR valve, Faulty fuel injector(s), Faulty camshaft position sensor, Defective computer. And many more. Which code you getting now though, the P0300?

welderman78 · #13 12-29-2011, 07:50 AM

yep that is the code thanks bro. Iam checking all the vacum lines this weekend.

bassplyer92517 · #14 12-29-2011, 11:36 AM

Quote:

Originally Posted by welderman78

yep that is the code thanks bro. Iam checking all the vacum lines this weekend.

One of my least favorite things to deal with is vacuum leaks

welderman78 · #15 12-30-2011, 09:28 AM

well i have solved the problem i a leak on the intake or injector 1,4,5 now how hard to fix. If i take the intake off will it warp.any is there any special tools need except the fuel line tools.