97 rough idling

[Twistingtommy]

hey i have a 1997 ford explorer xlt with a sohc v6 and when i am idling at a stop light or etc my car starts to shake every few seconds and the rpm are at 500 or just slightly lower but when i hold the brake and press the accelerater pedal its fine can any one help me with this problem thanks Tommy

 

[konaboy]

mines doing the exact same thing. I'm thinking plugs but curious to what others have to say.

 

[rhyno]

My 97 did that as well. I changed the plugs which were way too old, and cleaned the air flow sensor. Seemed to help. I think it was mainly the plugs as they were visualy worn down when looking at them.

 

[aldive]

Here are several things to do that should help the idle:

clean the MAF
clean the IAC
run a can of Sea Foam through the intake

Good luck .....

 

[Twistingtommy]

thanks everyone ill try that today

 

[spta97]

I always post this, but cleaning does not always help. I have had luck cleaning the MAF, but the IAC needed replacement (actually got worse after cleaning). To test, start the car and disconnect the harness. If it is not working great, the engine should start to sputter. If there is no change it is probably not working at all and needs replacing.

 

[aldive]

I always post this, but cleaning does not always help. I have had luck cleaning the MAF, but the IAC needed replacement (actually got worse after cleaning). To test, start the car and disconnect the harness. If it is not working great, the engine should start to sputter. If there is no change it is probably not working at all and needs replacing.

Same here.

 

[rocketboy52]

I understand MAF= Mass Air Flow
I'm not sure what IAC is.
Thanks in advance,
Erik

 

[aldive]

I understand MAF= Mass Air Flow
I'm not sure what IAC is.
Thanks in advance,
Erik

Idle Air Control

 

[Mbrooks420]

Some IAC's are sealed and can't be opened. I cleaned the one that did open, and it was only good for a few weeks.

 

[rhyno]

Yes, I initialy cleaned my IAC after it developed the dreaded howl. Did not work for me, but a replacement from AC/Delco was only about $50. Make sure to shop around and be careful where you buy them. The Pep Boys wanted $120 for the IAC they carried that fit my truck.

 

[Suren20]

I also cleaned the IAC and it didn't help my idle problem at cold start. I'm looking into replacing it, could please let me know where did you buy yours and was it ford or aftermarket ? any preference ?

thanks.

 

[410Fortune]

Also you guys asking the questions might try the search button, this way you dont have to wait for a response.
These are daily topics on this forum and covered extensively.

the valve body portion of the IAC should not go bad, the solenoid portion is all that you need to ever replace...

 

[aldive]

the valve body portion of the IAC should not go bad, the solenoid portion is all that you need to ever replace...

Mine is a one piece part.

Please explain the above statement.

 

[410Fortune]

OH they changed the design, sorry the older IAC's or at least the one on my 5.0L and my 4.0L OHV are two pieces, the solenoid comes off with two phillips screws.
The valve body section is just a plunger and spring, should never need replacing, I have $20 says the older style will bolt up and plug into your SOHC too...

'I should add I have never had an idle problem that was due to a dirty/failed IAC. Usually it is a vacuum, fuel, or spark issue (hahaha that narrows it down!)

 

[aldive]

I have only replaced one on my '99. Cleaning never worked for me.

 

[jcgraham]

My 97 V8 Merc Mount (150k)is doing the same thing...when at idle it is so rough you can feel it in the steering wheel and same on highway, and when accelerating there is a distinct flat spot/miss. Also a clicking when accelerating while cold. Couple of months ago I replaced the wires/plugs and an o2 sensor. After making a move across the country a month ago I have replaced the IAC and cleaned the MAS...drove fine for a couple of days and went back to rough idle and missing and the CEL came on. I got a P0133 x2 02 Sens slow response bank1/sensor1 and a P0304 x2 cyc(4) misfire. Since the wires and the plugs are ok and I read that 02 will code if you have a misfire I replaced the coil pack for that side. Ran awesome for 15 minutes until it warmed up and the CEL came on and started blinking and the rough idle/running started again. Tomorrow I will check the codes again and see what they bring. I am an amateur and am ready to push it off a cliff--any ideas would be greatly appreciated.
thanks
jc

 

[cculter]

I had the same thing happen, I changed plugs and wires. Works great now, just like brand new.

 

[mschacht]

Check your fuel pressure regulator. If your's has a vacuum line attached pull it off and check for wet fuel in the line. If you do, change it. Auto Zone has the best price, I found.

 

[thrawn5499]

I have a 94 navajo that has 175000 miles on it it is doing the same thing it idels a little rough when in park but when i am in gear it idles realy hard and the whole car shakes is this the plugs too?