Qualitycraft Racing Posted June 28, 2009 Report Share Posted June 28, 2009 wonderin if anyone knows about fords that dont idle right. i changed the fuel filter and tranny filter and the plugs . i also treated the intake with that seafoam stuff via the brake booster vacuum. the only thing that made it stop dying on me was the plugs, but now it will still idle from 400 to 600 up and down, up and down after the AC has been turned on and its in park. at least it runs now but the idle going up and down makes me think the IAC is acting up. any thoughts? Quote Link to comment Share on other sites More sharing options...
97car Posted June 28, 2009 Report Share Posted June 28, 2009 Is the a/c fully charged? It could be cycling on and off like that if low on freon. The map sensor can do that also. Take off the throttle body and clean both sides of the butterfly plate, and the idle air control valve would be a good thing to change or try cleaning first due to carbon build up. Quote Link to comment Share on other sites More sharing options...
Qualitycraft Racing Posted June 28, 2009 Author Report Share Posted June 28, 2009 thanks 97car, and you are correct. i finally had found the tidbit of advice i needed. some guy online told me to clean the air intake and AIC with INTAKE CLEANER not carb spray and then to disconnect battery and reconnect then take for a drive through full cycle of driving conditions and it worked!! apperently after you clean it correctly you must reset computer and let it re-learn idle with a cleaner intake. the AC works and doesnt effect idle at all now no matter if its in park , drive ect.. thanks for taking the time to help me out, i appreciate it. Quote Link to comment Share on other sites More sharing options...
txtom Posted June 28, 2009 Report Share Posted June 28, 2009 I have a 2000 with a 5.4 that has 200,000 miles on it. Every couple months, I get the rough idle, and it stutters on aceleration. What I find every time is an oily film on the MAF sensor located in the intake tube, and the throttle body butterfly is sticking due to oily build up. It appears to be oil vapor coming through the EGR system gumming up the components. I think it is a result of blowby from high mileage. This truck uses very little oil between changes, but the wife drives it mostly right now, and has a lot of start/stops. Engine vacuum will increase the blowby. And if you use the transmission in any way to slow the truck down, such as downshifting, that will raise the engine vacuum, adding to the original problem. Now, from personal eperience, when you buy the intake cleaner,( and I use the MAF cleaner) throw that damn little tube away before you clean the throttle body. You don't need it, and it is a pain to pull the throttle body off those trucks to get it out when it blows out of the nozzle. Quote Link to comment Share on other sites More sharing options...
Qualitycraft Racing Posted June 28, 2009 Author Report Share Posted June 28, 2009 I have a 2000 with a 5.4 that has 200,000 miles on it. Every couple months, I get the rough idle, and it stutters on aceleration. What I find every time is an oily film on the MAF sensor located in the intake tube, and the throttle body butterfly is sticking due to oily build up. It appears to be oil vapor coming through the EGR system gumming up the components. I think it is a result of blowby from high mileage. This truck uses very little oil between changes, but the wife drives it mostly right now, and has a lot of start/stops. Engine vacuum will increase the blowby. And if you use the transmission in any way to slow the truck down, such as downshifting, that will raise the engine vacuum, adding to the original problem. Now, from personal eperience, when you buy the intake cleaner,( and I use the MAF cleaner) throw that damn little tube away before you clean the throttle body. You don't need it, and it is a pain to pull the throttle body off those trucks to get it out when it blows out of the nozzle. hey thanks, now i wanna clean mine. when you say in the intake tube , how do you get to it? if im gonna clean my butterfly will it be right in there. i have to take the butterfly out correct? i'd appreciate it if you told me how. only thing is youre gonna have to be real specific. i barely know how to work on an easy old 350, muchless these new motors with computers and sensors and whatnot. anyway, if you have the time to post i'd appreciate it Quote Link to comment Share on other sites More sharing options...
txtom Posted June 28, 2009 Report Share Posted June 28, 2009 (edited) Actually, it was late last night when I typed that, and I meant to add the IAT (Intake Air Temp) sensor to the mix. It is the one that gets the oily vapor. The MAF sensor should be located by the air filter. You should have a big clamp that holds the air filter box together. When you pull the filter housing apart and take the filter out of one side, you can the MAF sensor in the other. It will be on the side leading to the intake tube, going towards the engine. Clean that sensor with MAF cleaner only. NO carb cleaner, brake cleaner, etc. Make sure it says for MAF sensors. now, about a foot or so towards the engine on the intake tube, you can see a couple wires leading to a sensor in the tube itself. On my 5.4, it is located in a flexible part of the tube. On that side of the housing that holds the MAF sensor, there is a clamp that holds the housing to the tube. Undo that clamp, and it will allow you to see the inside of the flexible part of the tube, and you will see the IAT sensor. Spray this sensor with the same thing you used to clean the MAF. Also, this sensor rotates in it's housing, make sure you can see through the sensor when it is installed. It will look sorta like the eye of a needle with a wire in the middle of it if indexed correctly. After spraying, allow the spray to air dry until you can see no residue. then put all the clamps back. For the throttle body, you should have a little plastic cover over the top of it that has two screws on one side, and 1 screw on the other holding it on. It is the cover that has the engine size molded on it. Take that cover off, and you will see where the intake tube connects to the throttle body. Remove the clamp securing the tube to the body, and move the tube out of the way. You will see the single butterfly in the horizonrtal closed position. If you see brown gunk around the edge of the butterfly plate, that is what you need to clean. Spray a shop rag with Intake cleaner, or you can use the same stuff you used on the sensors. Push the plate open, and wipe everything brown with the cleaner soaked rag. It will take a few passes. Loosen up all the big stuff. Take your can of cleaner, WITHOUT THAT DAMN LITTLE TUBE, and spray the area around the pivots . Make sure you also get the throat of the throttle body behing the butterfly plate as far as you can reach. You will see everything getting cleaner. Reassemble all this, and it should run better. My cleaner of choice is "Mass Air Flow Sensor Cleaner" made by CRC. The part number is 5110, and it is readily available at the parts stores. Edited June 28, 2009 by txtom Quote Link to comment Share on other sites More sharing options...
Qualitycraft Racing Posted June 28, 2009 Author Report Share Posted June 28, 2009 dayum , txtom , thanks for taking the time to type that out. since i have been under the hood for the last 3 days i can identify all the stuff youre talking about. thanks for speaking my language too. i'll get that MAF cleaner and get to it. thanks again Quote Link to comment Share on other sites More sharing options...
txtom Posted June 29, 2009 Report Share Posted June 29, 2009 You are welcome, and I want to add one more caution about the MAF sensor and the IAT sensor. When you clean these two items. spray them with cleaner ONLY. DO NOT wipe them, touch them, rub them, blow on them, take a q-tip to them, etc. SPRAY only. That MAF sensor has a little wire that becomes a $130 or so repair if it is messed up. So spray them with the cleaner only. The throttle body is ok as I previously stated. Now, if you forget and use the damn tube, (can you tell by now I don't like the damn tube??), You will have to remove the throttle body to get it out, and even then, you need a good suction shop vac. You would have to stick the vacuum hose down the intake and hope it will suck the tube out. I got lucky the first time. I do not present the opportunity for it to happen the second time. (Go back to my comments about the damn tube) Quote Link to comment Share on other sites More sharing options...
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