Rough idle and "Check Engine Soon" light - FIXED

[tonydp]

Does everyone else have a different motor than me?

 

[EasyRhino]

Does everyone else have a different motor than me?

Tony, can't tell what motor you have; however, if you think that you might have a leaking vacuum hose, it can be easier to replace them all. After all, there are all old at this point.

But, if you can't stand to do that, there is one way to figure out any any one of them is leaking now. Using an UNLIT propane torch (the kind used to braze copper piping), pass the UNLIT but blowing propane over the vacuum lines and hoses with the engine idling (obviously be careful). If you have a leaking hose, the vacuum will pull propane into the engine intake, causing the engine to speed up.

 

[MillerTimeX17]

Does everyone else have a different motor than me?

The part that you have circled as #2 is your pcv valve. It sits on the back of the valve cover facing the firewall.

 

[tonydp]

i did the pcv valve no luck. I'm gonna just live with it.

 

[jberg33]

Thank you

Thank you so much. I read your thread after having the same problem with my 2003 2 door Explorer Sport and found the same problem almost immediately. Off to autozone tomorrow, I would post the pics I took but out of town and forgot a card reader. Again THANK YOU, even my dad couldn't figure that one out.

 

[quinngs]

Just wanted to send a HUGE thank you to SyberTiger. After reading several forums and cleaning the MAF sensor and the IAC sensor the codes still wouldn't go away and I was still having the eratic idle problem. Found this post and checked the hose and sure enough there was the hole. With so many sensors and gadgets on vehicles these days it was a relief to fix this so easily and CHEAP. Went to Advance Auto Parts and bought a 1/2" Radiator 90' hose and cut to size........PROBLEM RESOLVED. Unhooked cables and no more codes. THANKS AGAIN FOR SUCH A GREAT POST.

 

[acornut]

thanx man some good info here I have a 99 4x4 explorer setting the same codes mine is intermittent, but you gave me some great ideas on where to start looking appriciated.

 

[rocco123]

Just replaced mine due to a small split. No CEL, but did have a intermittant rought idle. Seems to run fine now. Hopefully this the end of the idle issue.

 

[DanoDan]

Hey Syber... great details. I am guessing I have the same engine as you have, but I am not finding the elbow that show in your pics. I took off the noise shield (whatever that is called) and I looking all over. I am pretty noob-ish when it comes to this stuff. But I figure it is worth a try. You said the elbow was on the passenger side and connected to the PT. I hope I have that right. Any other tips on where that elbow is. Do you have a pic where you show the view from further back. That might help me find the elbow.

Once my car is warm it idles at about 400-500 RPM. The car will not stay running on its own until it is warm. As soon as I take my foot off the gas it dies. It occasionally dies when it is warm. I just spent $3K on a rebuilt transmission and I don't want to drop another chunk of cash on this problem.

Any help finding the valve is appreciated!

Thanks!

 

[SyberTiger]

This is what I said:

Specifically, the vacuum tube that runs from the PCV valve on the passenger side valve cover over to the throttle body air intake. The vacuum tube attaches to the throttle body air intake with a rubber elbow fitting.

I don't have any other pictures other than the ones I posted. However, if you look for the silver colored IAC in the picture below you will be close. I seem to recall it is center-left (drivers side left) up where you'd expect the intake to be on the top-front of the engine. Looks for the IAC as shown in the picture. Or follow the PCV on top of the passenger side valve cover and follow the tubing until you see the elbow near the IAC.

 

[Curtis]

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SOLUTION FOUND SOLUTION FOUND
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UPDATED ON June 22, 2008 - READ BELOW!
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I have a 2002 Explorer. The Check Engine Soon light stays on. The engine idles rough and sometimes dies as the RPM bounces between 650 - 800 RPM. At normal driving speeds and acceleration I do not seem to notice a problem. Oftentimes, at a red light, I'll put it in neutral and tap the accelerator just a tad to make sure it does not die on me at the intersection. Oddly, if you try to keep it idling at around 1000 RPM you'll see the tach jump up to 2000 RPM then back down to 800 RPM. It is very difficult to give it just enough gas and keep it a constant 1000 RPM when sitting there at a red light. Is there an easy way to read out the ERROR CODE without special tools? Anyone have a good guess as to what the problem is?

I have the V-8 engine and it has 91K miles on it.

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SOLUTION FOUND SOLUTION FOUND
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UPDATED ON June 22, 2008 - READ BELOW!
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[/IMG]

Well holy moly!
My dad complained his 02 was almost shutting off at a stop... So he had the code read - p1151 - the garage wanted to change O2 sensors... luckily he knows better and called as I tell him about this forum all the time.

After finding this thread, I sent him the pictures and location of the 'elbow' and he said his was cracked just like the pictures posted here!!!

He ordered the part from Ford - $44

And he could not be more happy!

 

[SyberTiger]

What is really sad is that this is apparently such a hugh problem for Ford motors equipped with the elbow hose piece and all the "Ford expert mechanics" want to change out all sorts of other parts. This should be an obvious component to check, first thing, when a customer comes in with the symptoms.

With all the people this thread has help I'm kind of surprised it isn't a sticky post.

 

[DanoDan]

I am still searching for the leaking vacuum tube/hose/elbow. But wanted to give you my thanks, Syber, for taking the time to try and get me on the right track!

 

[rocco123]

I vote this should be listed as a "Sticky". BTW, after I replaced my split elbow with a coolant hose section several months ago, I'm experiencing the same idle problem & just found that the hose is pretty soft & was pulling off. I need a better replacement.

 

[BigRondo]

I vote this should be listed as a "Sticky". BTW, after I replaced my split elbow with a coolant hose section several months ago, I'm experiencing the same idle problem & just found that the hose is pretty soft & was pulling off. I need a better replacement.

I second the notion. All in favor?

 

[jeffhsr]

Unbelievable

I just went through the same process you did and and in the end found the "exact" same problem as yours. I could have taken a picture as it looked exactly the same. I used good old duct tape for now...will try to order the part (thanks to your sleuthing) on line and replace it.

Good work!

 

[sirms]

***************THIS SHOULD BE A STICKY*************

Thanks! This was also my solution to the same issues!!!

Just went to autozone and got a short piece of heater hose that was same gauge/diameter, and had a right-angle bend.

Also cleaned IAC with electronics cleaner (also autozone).

Vehicle idles smooth as new now.

 

[rocco123]

I had the 90 degree heater hose too. After about a month it got very soft, and when I started the truck you could see the vac line suck down FLAT. Trying to order the correct replacement right now,but having the same issues of the dealer ordering the wrong part. Tonight i'll go over there & show them the tube assy.

 

[sirms]

Really...There I was thinking I was all smart and resourceful.

I'll give it a couple weeks and see how it looks.

If you don't mind, can you provide the part# and cost of the correct tube assembly????

 

[rocco123]

SIRMS, the dealer ordered the wrong tube on the first round. When I came back after ordering what we thought was the right one...again it was wrong, but on a hunch the parts guy had another tube sent over to see if it was a match. What I bought is a Motorcraft tube assy with part number(s) KCV-240 2L2Z-6A664-FA. It is an exact fit. Cost was 38 bucks. I hate to spend the money on a simple rubber & plastic tube, but don't want to have to keep an eye on it. Good luck with your repair, and let me know if yours gets soft & colapses.