Question about 1998 Ford F250 SuperCab

2 Answers

Engine missing rough idel and running at speed

Posted by on

  • 2 more comments 
  • skip2469 Oct 14, 2008

    engine misses and runs rough from idel on up. also check engine light comes on steady and thens starts to flash just after hard acceleration. also exhaust port temps are about 100 to 150 deg f. on front two driverside cylinders ( I would refer to them by proper cyl # but I dont know the proper sequence on this block 2006 5.4 triton in f-250

  • Buddy762 Nov 28, 2008

    Where do I look to find the Spark Plug and Cylinders?

  • james legros May 11, 2010

    what year is the vehicle and what engine

  • Anonymous Mar 26, 2014

    engine misses at idle speed-not apparent when at running speed

×

2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Check your coilpacks the 5.4 has a coil pack for each plug and they are known for going bad!

Posted on Oct 18, 2008

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Sergeant:

    An expert that has over 500 points.

  • Expert
  • 350 Answers

Hi you need to find out what the fault codes say but if the two cylinders are next to each other and are running to hot the miss-fire is on these two cylinders do a compression test on these two i suspect the head gasket has gone between the two if everything is ok have a look at the distributor cap and rotor yates210456

Posted on Oct 14, 2008

2 Suggested Answers

emissionwiz
  • 60691 Answers

SOURCE: engine runs rough at certain speeds 3.0 v6 flex-fuel 1999 ranger

Check and see if the EGR valve is leaking, to check this spray water on it at idle, if the water steams off the valve is leaking and is the source of your problem, also are you sure you hooked the new DPFE sensor up right? re-check it..

Posted on Nov 23, 2008

jturcotte
  • 6811 Answers

SOURCE: rough idel and no power on my 95 aspire changed

Check for leaking vaccum lines from the engine intake manifold. If no leak, test the IAC motor and clean out the air bypass passages per instructions below. Let me know if this doesn't solve the problem or you have any questions.


OPERATION
The Idle Air Control Bypass Air (IAC BPA) valve consists of an idle air control valve and a bypass air valve. The bypass air valve functions during cold engine conditions to increase engine idle speed. It consists of a thermowax bead and a valve.
Engine coolant is directed around the thermowax, which opens and closes the valve. During cold engine operation below 140°F (60°C), the thermowax is contracted enough to allow the valve to open. As the coolant heats, the thermowax begins to expand. When the coolant reaches temperatures above 140°F (60°C), the thermowax expands and closes the valve.
The valve controls the amount of throttle valve bypass, which ensures a smooth idle under all engine operating conditions.

  1. When the engine is cold, air flows through the valve during all modes of engine operation, to maintain the factory set idle speed.


TESTING See Figures 1, 2 and 3 (if you don't have an ohmmeter, skip this test)

  1. To check the Idle Air Control (IAC) valve resistance, unplug the IAC valve connector.
  2. Connect a high impedance Digital Volt Ohmmeter (DVOM) to the terminals.
  3. Measure the resistance.
  4. The resistance should be 7.7-9.3 ohms.
  5. If the resistance does not meet specification, replace the IAC BPA assembly.
jturcotte_378.gif

Fig. Fig. 2: Connect an ohmmeter to the IAC valve; the resistance should be 7.7-9.3 ohms


At this point, if your IAC checks good, I recommend you take out the 4 screws seen above, remove the motor, and clean out the air passages/valve with carb cleaner. Also remove the big (3 inch diameter) hose from the throttle and clean out the throttle body, if dirty.


If the IAC tests bad, go to the removal and installation directions below.


The next test requires a scanner. If you don't have a scanner, skip this test.



  1. To check the BPA valve function, remove the BPA valve from the engine.
  2. Wait until the valve reaches room temperature. When the valve is cold, blow through the air inlet and verify that air flows freely through the valve.
  3. Heat the valve with a hair dryer; the air valve should move out and block the passage.
  4. If the valve does not function as specified, replace the IAC BPA assembly.
  5. To test the solenoid, connect a scan tool to the Data Link Connector (DLC).
  6. Turn the key ON and enter the simulation test.
  7. Access the IACV Parameter Identification (PID) and turn the dial to cycle at 75 degrees.
  8. Listen for the IAC solenoid to click when using the simulation test.
  9. If the solenoid clicks it is working properly.
jturcotte_379.gif

Fig. Fig. 3: Idle Air Control Bypass Air (IAC BPA) valve assembly components


REMOVAL & INSTALLATION

  1. Disconnect the negative battery cable.
    CAUTION
Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.
  1. Drain the coolant until it is at a level below the Idle Air Control Bypass Air (IAC BPA) valve.
The lower coolant line should be disconnected after the valve is separated from the upper intake manifold.
  1. Tag and disconnect the upper coolant hose from the valve.
  2. Unplug the valves electrical connector, then loosen the two nuts and two bolts attaching the valve to the upper intake manifold.
  3. Pull the valve from the manifold and disconnect the lower coolant line from the valve.
  4. Remove the valve and gasket from the engine.
To install:
  1. Use a scraper to clean any old gasket material from the valve mounting surface.
  2. Install a new gasket and connect the lower coolant line to the valve.
  3. Install the valve and its retainers. Tighten the nuts and bolts to 71-88 inch lbs. (8-10 Nm).
  4. Engage the valves electrical connection and the coolant hoses to the valve.
  5. Fill the cooling system and connect the negative battery cable.

Posted on Dec 05, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Idel's is rough only some time, its not rough all the time,


ZULFIQARDR HAS A TOYOTA CAMRY CAR, SOUND LIKE ROUGH IDLING COULD BE CAUSED BY WEAK FUEL PUMP,DIRTY FUEL INJECTORS, FOUL OUT SPARK PLUGS CAUSED BY LEAKING FUEL INJECTORS,LOW IDLE SPEED, CHECK IDLE SPEED CONTROL COULD BE TOO LOW ARE FAULTY LOOK FOR VACUUM LEAKS ON INTAKE MANIFOLD.BAD LEAKING ENGINE VALVES.

Feb 05, 2012 | Cars & Trucks

1 Answer

I have a 95 blazer 4.3 engine comes up with a random mutltiple missfire.It idels rough and runs rough going slower speeds 25-35 mph,but at the speed limit or faster it runs alot better,what could be the...


Sounds like needs a tune up, New spark plugs-wires, could be running on 5 cil. put a new fuel filter on, this helps sometimes. Buy gas treatment at Autozone, you may have water in your gas, run all the gas out and buy gas at a different place than before. Try and get 91 oct. better fuel may help.

Feb 15, 2010 | 1995 Chevrolet Blazer

1 Answer

Missing


Sounds like a load miss. Chk plug wires for deterioration and or cross firing. Wires should not cross over each other. Worn plugs load wires causing increase spark out put increasing cross firing potential

Apr 30, 2009 | 1986 Ford F 250

3 Answers

Rough idel/no power


0475c6f.jpg As a former Audi technician, I can pretty much guarantee the coil packs are your problem.

Jan 25, 2009 | 2004 Audi A4

3 Answers

Need info on rough idel 5.9 cummins


bad injector?
easy to test with vom, just check from terminal on injector to ground if one reads different thats the problem, you do need to disconnect wire to check, my help is free and will be glad to help further just vote fixa..LOL my rating is all I care about. Hope yu can help me too.

Dec 19, 2008 | 2004 Dodge Ram 2500

2 Answers

Backfiring, rough idel


I would check the exhaust pipe a little closewr. White smoke can also mean a blown head gasket. Check the tail pipe to see if moisture is present. Also check coolant level. A blown head gasket can also cause related problems.

Bill

Nov 19, 2008 | 1999 Pontiac Grand Am GT

2 Answers

Rough Idel & Engine Miss


You may have water in the spark plug hole, or a shorted plug wire, pull #4 wire and look for water residue and a possible burn mark on the plug wire were it goes over the plug.

Aug 23, 2008 | 2001 Ford Focus

Not finding what you are looking for?
1998 Ford F250 SuperCab Logo

Related Topics:

318 people viewed this question

Ask a Question

Usually answered in minutes!

Top Ford Experts

yadayada
yadayada

Level 3 Expert

60667 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21936 Answers

Fordexpert

Level 3 Expert

5331 Answers

Are you a Ford Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...