multiple diagnostic codes.

[jab0106]

explorer with check engine light and O/D off light on scanned:

PO171 BANK 1 LEAN
PO174 BANK 2 LEAN
PO741 TCC SYSTEM MALFUNCTION
P1506 IDLE OVER SPEED ERROR
P1740 TCC INDUCTIVE SINGINTURE MALF.


WAS TOLD ONE WAS INTAKE MANIFOLD LEAK, REPLACED INTAKE MANIFOLD GASKETS. CODES CLEARED.

NO NET CHANGE IN CAR SYMPTOMS:

Rides Smooth 1/3 Time

2/3 Time O/D light flashes and following occurs:
Rough, variable idle [mainly low]
Choking off while in Drive
Hard thump @ 1/2 gear change [consistent symptom, others more recent]

O/D light occurs intermittently with no noticeable cause other than possibly reaching gear 4. Some days light is on @ 1st crank; other days light comes on only upon reaching cruising speed approx. 60 mph for a mile or two. O/D light also cuts off with no noticeable cause, usually after riding below 60 and above 20 for an extended period.

WOULD LIKE TO KNOW ALL FIXES, BUT MOST IMPORTANTLY THE QUICKEST ROUTE TO KEEPING CAR CRANKED [service said idle motor probably needs replacing, but that intake manifold gaskets could cause that code--obviously not the case]. CUT OFF TODAY WHEN SHIFTING P TO D.

Any and all help appreciated.

 

[1998explodersprt]

explorer with check engine light and O/D off light on scanned:

PO171 BANK 1 LEAN
PO174 BANK 2 LEAN
PO741 TCC SYSTEM MALFUNCTION
P1506 IDLE OVER SPEED ERROR
P1740 TCC INDUCTIVE SINGINTURE MALF.


WAS TOLD ONE WAS INTAKE MANIFOLD LEAK, REPLACED INTAKE MANIFOLD GASKETS. CODES CLEARED.

NO NET CHANGE IN CAR SYMPTOMS:

Rides Smooth 1/3 Time

2/3 Time O/D light flashes and following occurs:
Rough, variable idle [mainly low]
Choking off while in Drive
Hard thump @ 1/2 gear change [consistent symptom, others more recent]

O/D light occurs intermittently with no noticeable cause other than possibly reaching gear 4. Some days light is on @ 1st crank; other days light comes on only upon reaching cruising speed approx. 60 mph for a mile or two. O/D light also cuts off with no noticeable cause, usually after riding below 60 and above 20 for an extended period.

WOULD LIKE TO KNOW ALL FIXES, BUT MOST IMPORTANTLY THE QUICKEST ROUTE TO KEEPING CAR CRANKED [service said idle motor probably needs replacing, but that intake manifold gaskets could cause that code--obviously not the case]. CUT OFF TODAY WHEN SHIFTING P TO D.

Any and all help appreciated.

the light is turning on at 60mph probably due to the torque converter clutch circuit (or just mechanical) failure. the torque converter clutch is turned on only at highways speeds to give the transmission a true 1:1 ratio.

usually when the TCC wont release, the motor bogs down a bit the slow and slower you go, until it finally dies at idle. seems you are having maybe intermittent problems with the TCC circuit. could just be a bad TCC solenoid.

for the lean bank 1 and 2, i would take a stab and say its gonna be the intake manifold leak. usually when BOTH banks give the code its a good hint in that direction.

as for the idle over speed: im not too familar with that code, but do you actually have a high idle? or is it just the code with no symptoms?

 

[jab0106]

it actually did idle high for a long while, now after the intake manifold leak was corrected, it idles ok in park or neutral, a bit too low when put in drive.

so what to do for the TCC problem? is there a possible home fix?


also, will probably replace the idle motor at the house. anyone familiar with how to do so for this particular car? i've heard it wasn't that hard.

 

[1998explodersprt]

it actually did idle high for a long while, now after the intake manifold leak was corrected, it idles ok in park or neutral, a bit too low when put in drive.

so what to do for the TCC problem? is there a possible home fix?


also, will probably replace the idle motor at the house. anyone familiar with how to do so for this particular car? i've heard it wasn't that hard.

i would have a to see if you can find info on the TCC and how to test it. if you have a haynes/chiltons manual you can see if they say anything in there. if not i might be able to pull something for you and post it up on testing this circuit/part, but dont hold me to it.

as for the IAC, what motor is this? if this is the v6 OHV engine, it is down syndrome retardly easy to replace. its as simple as disconnecting the sensor which sits right on the throttle body, unbolting two bolts (i think its two, lol might be three) and then swaping in the new one. however, before doing that i would suggest cleaning it out first. mine was having some issues a while back, and a good cleaning with carb cleaner sufficed.

 

[jab0106]

appreciate the help, will definitely try cleaning the current motor first.

anything to do with TCC circuit is foreign to me. i have no clue about it. any information, how to test, etc. would be greatly appreciated. have to replace the brake pads and rotors tomorrow, ill clean the idle motor and scope out for any other problems, and TCC info would definitely be good to have then. thanks!

this is a great site btw. for all the problems i have with my explorer, this site comes in handy

 

[ThePhoenix]

and the P0171-0174 codes might be spark plug wires. I had BOTH codes and they went away when I changed plug wires (I had already done plugs and it helped but still had a code)

 

[jab0106]

cleaned the idle motor, and seems to be running much smoother, it was a bit gunky before. also, definitely an easy thing to do, sits right up top.

changed the brakes and the grinding went away also, although there was nothing evident wrong with the pads or rotors??

and the auto shop also suggested replacing the plug wires but i gotta wait to make bank haha. appreciate the suggestion, it confirms it a bit.

 

[ThePhoenix]

$38 bucks including shipping for a set of wires off of RockAUTO EBAY STORE...no excuses....

 

[jab0106]

haha true phoenix, but the auto shop cost me 338 an change to replace intake gaskets, so i gotta wait til payday friday.

also update:

cleaning the motor did NOT fix the problem, still does the semi-stalling intermittently, more often during quick, turning stops after a bit of stop and go city driving. not near as often as before replacing the gaskets and cleaning the motor, but still happens. and the "grinding" i have been feeling is also still there, only when the other problems occur, and its definitely not anything with the brakes, im thinking tranny, but it FEELS like the rotors are getting fd--ive done it before :/ anyhow, when the o/d light is off, NO TROUBLE, when it is on, LOTS of trouble INTERMITTENTLY. lately the light has been on perpetually and tranny is shifting a bit harder. also, the trans fluid is nasty which im sure makes it all the worse.

im guessing the TCC and fluid are the MIP problems atm. so any info on TCC?

 

[jab0106]

so i pulled up to a stop sign, and the thing cuts off. when i go to restart, cranks up fine. put into gear and cuts off. every time. replaced the IAC valve and the thing could be moved, but the shaky, low idle remains that threatens to cut off again. i guess its a faulty TCC solenoid...? or entire torque converter? i have no idea. becoming very cumbersome. guess im gonna have to find a good tranny shop tomorrow.

anyone know of an average price to replace the TCC solenoid, if that is in fact the problem?

 

[Turdle]

disconnect your maf sensor and see how well it runs without it please.

ignore any new check engine light-

 

[jab0106]

took it to a tranny shop, had the guys take a look and test drive it although the light wasnt on atm, called back later saying the tc was locking up the engine, and that it was probably coming apart causing the grinding feeling. had the trans pan dropped and found metal. guess next step is a rebuild $$$. oh well.