Engine Revving

Does it seem like the transmission is slipping?

when it does this it acts as though it dosen't have any power. it slipped once on me while I was driving up Lookout Mountain but other than that one time no.

This is a tough one because I don't have too much to go on. A bad throttle position sensor will cause the engine to rev up and down, but usually when the engine is under a load, you don't feel it.

As far as the transmission, is the fluid clean and full?

Finally, I have to honestly say I don't believe it has anything to do with the radiator unless it is overheating or leaking ATF from the cooling lines to the radiator.

Has the check engine light ever come on?

The check engine light came on once when the vehicle overheated. As I stated before the radiator has a leak and all the antifreeze leaked out and it overheated with my wife. She stopped as soon as the light came on and turned off the engine and waited until help arrived. We did not have problems with the engine revving until after the radiator began to leak.

2006 Ford Explorer (~75k miles) started to have unusual rpm increases while accelerating (both initial and maintaing speed). Every now and the then the temp gauge will go all the way up and the warning light comes on - and then quickly goes back to normal. This usually happens with the rpms go up to 3 for about minute. What are the possible causes of this behavior?

The RPM issue can be a few things. Check to make sure there are no vacuum leaks. Also, check the throttle position sensor. If the check engine light is on, have the computer scanned for trouble codes. Most parts stores will do it for free.

As far as the temp, make sure the coolant if full. If it is, check the thermostat and cooling system for restrictions.

Thank you! There are no warning lights at all. There are no warning lights on my dashboard whatsoever. Had a throttle body cleaning (in addition to oil change, power steering exchange, fuel system service) today. They were going to do a transmission check, but mine is sealed so they couldn't get to it. The 18 point service check list from Mobil Express shows everything is good.

The transmission is sealed, but there is a check point on the side to make sure the fluid is full and clean. They should have checked that.

As far as the engine temp, do you think it is actually getting that hot or do you feel there is an electrical issue?

I do not think it is actually getting hot. While the work done yesterday appears to have helped a little, it is still doing it. My mpg is usually around 17 and now it is at 15.8. This morning, the check tire pressure light came on for 5 mins and then went off. Just had them checked yesterday and they were fine. I am going to take it to Firestone today with a print out of this message string. I truly appreciate your help!

my SUV has a mind of its own in the last three moths my car has done this now three times it revs and rpm goes up when at a stop light or stopping when holding brake the car jumps forward like it wants to take off. also, has done it on the highway rpm will go up when i am on sixty four just cruising. please help, I have four little ones in the car all the time, thank you

try cleaning throttle plate on both sides and IAC hole with choke cleaner no need to remove throttle body. then check for either a leaking vacuum brake booster or check valve if it continues. if you apply the brakes while in park you may hear a hissing sound inside car if you do then have a mechanic check it as booster is bad.

The CEL has not came on once but for about 2 weeks when driving the rpm needle will go from 3 back to its normal place. The mechanics cannot help me because my CEL has not come on yet. I had a major tune up about 5 months ago which included spark plugs and wires, pcv valve, fuel and air filter. I just passed emissions inspection exactly 1 month ago. Need help with what is going on with this SUV.

Is the engine reving or is the tach just jumping?

The tach is jumping after the car chages gears.

From my experience, the light won't come on. Every one that I have seen have had the same problem, the tach itself was bad.

2003 Ford Explorer Four Wheel Drive Automatic

My truck just started the other day dying when i slow down to come to a stop, not every time but a majority of the time. Throw it in neutral and she restarts with no problem however the oil pressure and charging system lights will come on when she does die. If i have her in park, neutral, or drive with brake applied she starts revving between 400 and 1100 rpms... If i keep her in neutral when at a stop I can keep it from dying. We had the fuel filter replace and fuel system flushed and they said nothing was wrong. Well something is wrong, please help

It sounds like a bad idle air control valve. Has the check engine light come on? Have you checked for vacuum leaks, EGR...?

I had it checked for vacuum leaks and there isn't any. Don't know what EGR is. No check engine light, had codes check and it hasn't thrown any codes. Been told by a few people that it could be that damn idle air thing...this trucks been in the shop at least 3 times since i have owned it for one thing or another.

While driving- rpms will just drop & car will die. No "Check Engine "light comes on. No warning. Will put in neutral and start up again, sometimes right away, sometimes after 3-4 tries. If sit for awhile, will go again for some miles before stopping again. Had fuel pump/fuel filter replaced, idle solinoid cleaned, a/c temp sensor replaced. THIS ONLY HAPPENS WHEN OUTSIDE TEMPS ARE 75 DEGREES AND UP. As long as it's cool outside, no problem. While driving one hot day, started acting up, dying, had to keep foot on gas/brake to keep moving, ran into rain, cooled off, car started running fine again!!! Ford dealer ran complete diagnostic, could find nothing. Said it'll have to be acting up to locate problem as no "Check Engine" light comes on. Help, Help, Help

Intermittants can be tough. I would focus on the ignition system first. Using a cold damp towel (Keep one in the fridge) you can cool off components to bring down their temperature and hopefully cause the no start.

I would start with it on the ignition switch when the no start is happening. I am suspecting the tranciever ring around the ignition lock. It should set anti-theft codes, but this will not affect the check engine light.

IF you have tilt steering, try moving the column up and down to see if it starts when the no start is present.

Maybe I didn't make the focus of my question clear-or I'm not understanding your answer. Why does my Explorer just stop running while driving (usually after 20-30 miles of steady driving) and it happens when the outside temps are warm to hot, but not in cooler (below75) weather? "Check Engine" light doesn"t come on. What could be happening in the mechanics of the car to create this problem? Why doesn't a Diagnostic or Scan show anything when I bring the car in to be checked?? Again, Help, Help, Help. I had to cancel a trip this weekend because the weather is not quite cold enough for me to feel confident that my Explorer will get me from Point A to Point B.

There is most likely an electronic problem within the ignition system that is affected by temperature. I listed how I would start troubleshooting. Cel engine light is related to emissions and there may be codes in the compurter related to anti theft.

OBDII scan codes
P0135, P0141, P0155, P0161
P0743, P0750, P0755, P0760, P0765
plus 1451 and 1747

O2 wires look OK (all four)
Lever shifts on side of tranny when put in gear

Car stalls in each gear
Starts fine, revs fine in neutral

P0135 Oxygen Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)

P0141 Oxygen Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)


P0155 Oxygen Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)

P0161 Oxygen Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)

P0743 Torque Converter Clutch Circuit Electrical
P0750 Shift Solenoid A Malfunction

P0755 Shift Solenoid B Malfunction
P0760 Shift Solenoid C Malfunction


P0765 Shift Solenoid D Malfunction


P1451 Diagnostic Module Tank Leakage (DM-TL) Switching Solenoid Control Circuit Signal Low

P1747 EPC Solenoid Short Circuit

as you see all codes indicate a short circuit of some sort
start by checking the fuses check if you have any missing (empty cavity )
check the wiring harmess

there was a high pitch sound from under the hood. It was consistent from when I start it, idling (not as loud), to accelerating (got louder). At one point coming up the hill, sounded like it was crackling/rubbing until something broke/snapped. I looked in the review mirror and saw a circular piece rolling. Tried to look for it but couldn't find it. Any thoughts?

Have you checked the belt and the belt pulleys? How large was the part you saw and what color?

My friend chased a sound sorta like you are describing

It seemed to come from everywhere

He changed the alternator thinking that was it (whereas he shoulda took the belt off and fired it up to eliminate any belt driven stuff)

Turns out it was coming from the throttle body, a real annoying, high pitched, kazoo kinda sound

The solution was to clean the inside of the throttle body, the butterfly, and actuating the butterfly and cleaning the backside of it with "throttle body cleaner"

Listen around the throttle body to see if you have the same problem

Keep us posted on progress

The medic

Ok sorry!

I had an advertisement that covered half of the "question", when i read it the 1st time. Upon my submission, i got to see the rest of it. Then i understood why j&n responded with the "part and color" answer

The medic

Engine Performance problem
2003 Ford Explorer 6 cyl Four Wheel Drive Automatic 103k miles
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While idling in park, about every 5 seconds, my RPMs drop from around 900 to 500. I also, hear a click coming from the engine when it happens. Sometimes quits when I shift from drive to park.

I find some ford products are bad for this and I feel you may have the same problem. If you remove the plastic cover from the top of the engine you will see a cylinder looking thing that sits higher than anything els. It sits kinda at the back in the middle, there will be a plug from which you will see wires. This is the air bypass valve. What I have done with two different fords is, Have some one hold the brake with it in drive or keep it in park, you want it to run rough or at low idle. When you do this take a small wrench or screw driver and tap on the air bypass unit, you my want to tap hard because it may be stuck. If this is the problem the ford will rev nice after you tap the part. Two screws hold it on and it is never found on the computers in the garage. 100 bucks for the dealer part but worth it. Hope this helps.

Vehicle began to buck at certain speeds/rpms. Once it begins to buck, I can adjust the pedal to either slow down a bit or wiggle the pedal and then accelerate to where it kicks into passing gear and the bucking goes away. But once I'm in that 1800-22000 rpm zone, it will do it again. No codes. In fact, the only code ever to come up was the Evap cannister has a small leak and pops on once in a while.
Otherwise truck is very quick and strong. Drove it like this to South Carolina and back and got great gas mileage. I replaced the IAC pump, the plenum gasket, cleaned the throttle body and flange, changed the plugs and checked the wires the best I can. Any ideas? Thank you for your time.
John

Lack of acceleration,chugging,hesitating,bogging etc. could be caused by one of the following below.

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard.

Was fine and stopped at a red light and this problem occurred.

Check and test the crankshaft position sensor this is the one that measures the engine RPM

See if there are aney trouble codes in the ecu and try cleaning the maf sensor.

last week ?about truck has no power. no codes,fuel pressure 60psi,check exhaust pulled convters off no change,tps tested good,maf new,conpression test 125 on one cyl,vac test 18 at idle runs good at idle up to about 2000rpm drives no power no back fire clean exhaust no smoke ????help

Check the ignition timing and also the knock sensor. Your fuel pressure is on the low side-should be 60-65psi both KOER and KOEO recheck with and w/o the fuel pressure regulator-w/o vacuum should rise about 10psi over normal