4.0 SHAKES AND UNEVEN IDLE AT IDLE

[crabbman]

Hello some how on a start up the engine shakes with an uneven idle.
When i put it in gear it still shakes but when i add a little throttle it does one big shake and then settles down.
Of course when it warms up a little bit later it runs really well and steady and smooth.
Not sure where to start as i probably need some part and not knowing which part.
I will wait for reply.
160000- miles on factory engine.i have not added oil between oil changes (every 5000 miles).

 

[derfderf]

Sounds like a throttle body (IAC) cleaning is in order for starters.
The IAC (idle air control) valve is also probably dirty.
Use throttle body cleaner, NOT carb/choke cleaner.

Start with engine off.
Be sure to hold the throttle plate open and get the backside well.
Spray into the bore. Have a rag ready to catch the scuzzy liquid that drains back,

There should be a small opening at the front bottom of the throttle body -- this is the IAC. Spray liberally.
Start the engine. It will stumble and be difficult to keep running until all the cleaner gets burned, This is totally normal.

I am new to Fords, so I do not know if you can manually actuate the throttle plate under the hood on a drive by wire car -- I don't one (drive by wire)
Ideally, you work the throttle while spraying cleaner into the bore and at the IAC to free it up. Learning to do this without stalling the engine is just a matter of practice.

Pls report back

 

[crabbman]

Thank you d.d. I understand. I will do this tomorrow after work.
I am attempting to do Fuel Filter replace.
Also Pcv valve, I beleive i may have been givin the wrong part,so after work i will go to oreillys.
Also spray and clean IOC , Throttle Body as well as MAV Sensor.. I have the correct sprays from my other daughters Gmc Yukon.
Thank you again.

 

[derfderf]

Thank you d.d. I understand. I will do this tomorrow after work.
I am attempting to do Fuel Filter replace.
Also Pcv valve, I beleive i may have been givin the wrong part,so after work i will go to oreillys.
Also spray and clean IOC , Throttle Body as well as MAV Sensor.. I have the correct sprays from my other daughters Gmc Yukon.
Thank you again.

Words of wisdom:. Do ONE cleaning at a time, then let it cool all the way down. If you change out parts and clean 5 critical sensors or valves at the same time, you will never know what fixed your problem. So the next time it happens, you'll still have no idea what the problem actually is.

Does this take longer? Sure does, as it is a cold startup issue. But ultimately if it takes you 5 cold start evenings after dinner 1 each day during the week to do the cleanings one at a time, you end up with a problem free car AND forevermore the knowledge of exactly how to resolve the issue if it reappears.

Based on your description, the problem is an unsteady idle when cold, but a rev of the engine helps to smooth it out.

The symptoms scream IAC and sticking throttle plate. I am not saying the other sensors will not benefit from a cleaning, nor am I saying that you shouldn't have the correct pcv valve installed. And if that is the original fuel filter it is definitely due for a change.

But remember above all else:. The key to troubleshooting and LEARNING from it is to change ONE variable at a time. There are exceptions to this but it holds true 99.5% of the time.

A professional mechanic who has seen 137 Explorers come in w the exact same symptoms will troubleshoot it the first time, then apply the knowledge he's gained to the next 136. That is a different scenario, though, where time = money and the money is yours....

 

[crabbman]

Thank you. D.D. Now that's what I call a great answer with J.F.K. inspiration.
I will do this over a few days time.
This is my daughters Explorer and we need to wait a month to collect our money for it is headed to glenwood springs transmission shop for the Tranny is shot, They want $2700 for a complete removal/installation. I have to do this for my body and brain would have real problems attempting this 100 hour job.I am 63 years old,dos'nt show but inside it does.
Good day.

 

[derfderf]

Thank you. D.D. Now that's what I call a great answer with J.F.K. inspiration.
I will do this over a few days time.
This is my daughters Explorer and we need to wait a month to collect our money for it is headed to glenwood springs transmission shop for the Tranny is shot, They want $2700 for a complete removal/installation. I have to do this for my body and brain would have real problems attempting this 100 hour job.I am 63 years old,dos'nt show but inside it does.
Good day.

Tranny throwing codes ? Which ones?

Rough shifting, shift flares? I just helped a buddy Diag a bad alt. During the series of events it threw 4 tranny codes. Two different shops, one being a Ford dealership, did not bother to clear the codes to see if they ever did. Quoted him a complete tranny rebuild based on the codes alone. I cleared them. They never came back. Savings:$2700.

Buyer beware. Easiest scam in the industry. Because very few know how it works on the inside. Could just be some bad solenoids....

 

[crabbman]

Hello,I just had OREILLYS do a code scan and all i got was a mis- fire in #6 spark plug. That is all. I did a complete wire and plug change last Saturday.
We have driven the explorer the last year and it has the classic stay in gear problem. I was told by 1aauto to change the gasket for the valve body inside the transmission. I was to look for a blow-out of the gasket on the valve body. I FOUND NO BLOW-OUT. I went ahead and installed a new one any way. Took the car for a spin and now it is way worse. Reverse,forget it or wait five minutes to get it. It will take drive 3,2,1 but it will not hold a gear going on flat ground and up a hill it goes nuts and will go into neutral. I was looking to adjust bands for i heard you can do this to trannys. Not so with ford explorer. So it has 160,000 miles on tranny and I believe my skills as a mechanic are not up to tranny level.Hey sort of giving up here but we need this suv needs to be a suv and not sitting in our garage. I did hear about a solenoid relplacement but not sure where to go with anything. The engine seems to be peppy and strong with no strange noices.

 

[derfderf]

Have you taken it to a Ford stealership and eaten the diag fee to have them diagnose it by the symptoms and codes (or lack thereof)?
I am not fond of visiting the stealership unless I absolutely have to.

In this case, it MAY make financial sense, in that $100 to find out EXACTLY what is going on (which parts are failing and why it behaves as it does) Make them explain A LL of the technical details so you get your money's worth out of the diag visit and know exactly what's wrong and exactly what is needed to fix it and WHY.

I'm serious. Squeeze every last technical detail out of them and you will have gotten 1/2 your money's worth for the diag.

May beat $2700 in unnecessary repairs

 

[crabbman]

Thank you. I have a Tuesday afternoon, the 20th, drop off at dealer.
I have had good results from other times I have been here. I have to do an engine Diagnostic first before I do anything with Transmission possible repair.. I have a good game plan and sure hope for the best of decisions ahead.. hope the codes will be nominal or none.
Thank you again for help.