Stalling in Gear

[Mamba42]

Hello All,


I have a 2002 Explorer XLT 4.6L with 165000 miles.

I was driving my Explorer back from Idaho yesterday and stopped at a rest area, when I came to a stop there the Explorer started shuddering a bit and the check engine light came on. I put it in park and it stopped shuddering. I started it again and it was fine in park but once in gear again it felt like it was about to stall until I accelerated and everything was fine (no more check engine light). Once I back in the city and off of the interstate, the same issue came up at stop lights (it would almost stall), though the check engine light still hasn't come back.

So, basically, my issue is that whenever I put the Explorer into gear it acts like it is about to stall (though it hasn't actually stalled yet, it just sputters until I give it some gas). Also, this only happens when it is warmed up, as the problem was not there this morning until it was driven for a bit. I connected my scan tool and it hasn't thrown any codes (which is weird, since the CEL came on, but it then shut off and hasn't come back). Does anyone have any idea what my problem could be? I have done a bit of searching on my symptoms and have found possibly the EGR or torque converter (though I have no shifting issues and my fluid is clean).

Also, about a month ago I replaced my IAC valve (with another Motorcraft one). That fixed my previous idle issue, and had been running perfectly for about a month.

If anybody could help me out here, I'd really appreciate it!

Thanks in advance for anything!

 

[Mamba42]

Anybody have any idea what it could be?

 

[imp]

Anybody have any idea what it could be?

Torque converter clutch (TCC) is CONSTANTLY ENGAGED. This "kills" the engine whenever an attempt is made to hold the vehicle standing still, with the transmission in any gear other than neutral. Try slowing down to about 10 mph, then shift to neutral and stop. If engine idles normally when stopped in Neutral, TCC is engaged. This condition is exactly the same as stopping a vehicle with a manual transmission without disengaging the clutch.

Cause? Most likely, failed TCC solenoid, within the transmission. Less likely, mechanical condition within the torque converter itself, preventing clutch from disengaging. Even less likely, stuck valve within valve body in transmission, which the solenoid it trying to move, but cannot.

A "trouble code" should be present to further narrow down the cause. imp

Edit: Re-reading your post: EGR valve stuck wide open COULD cause bad/no idle condition. This would certainly cause a trouble code, as the EGR valve position is continually monitored by a sensor called the "DPFE" sensor.

Have one of the parts stores check for codes. It's possible your code reader will not read TRANSMISSION trouble codes.

 

[Mamba42]

Thanks, imp. I will see if the part store can pull a transmission code. Do you have any idea of the TCC solenoid cost to replace, roughly?

I read a how-to on that, and it didn't seem to difficult to do on my own but unfortunately I'd have to take it to Idaho again because I don't have the facilities to do it here.

I appreciate the reply!

 

[Mamba42]

So I checked out the specs on my code scanner and it does read transmission codes. It is somewhat new (2 months), so I didn't know off-hand if it did or not.

Also, could it be the solenoid if the issue only comes when the car is warmed up? It seems like it would be stuck all the time, not only when the car is warmed up. I don't really know anything about the TCC solenoid (or much about transmissions in general), but would it make a difference?

Thanks,

Jared

 

[imp]

So I checked out the specs on my code scanner and it does read transmission codes. It is somewhat new (2 months), so I didn't know off-hand if it did or not.

Also, could it be the solenoid if the issue only comes when the car is warmed up? It seems like it would be stuck all the time, not only when the car is warmed up. I don't really know anything about the TCC solenoid (or much about transmissions in general), but would it make a difference?

Thanks,

Jared

The transmission will ALWAYS remain in high gear (5th) without TCC engagement until it reaches a certain operating temperature. In real cold areas, this has taken several miles, in my experience. The tachometer is the best observation tool to spot TCC lock-up while driving. Thus, when first starting out with a cold transmission, the computer does not KNOW there is an issue causing TCC non-engage, until the temp. gets high enough for it to "ask for" lock-up; that's when it "sees" lock-up failed, begins throwing flashing OD-OFF light.

I bought the solenoid module for mine on ebay about $200 as I recall, the module contains all 8 solenoids (for 5R55S trans) mounted fixed on a common base; you cannot replace just the bad one. If you go that far, removing module, look for particles of yellowish-colored metal (bronze). They are the bits of broken plunger-guide from the solenoid, if that's how it failed (mine did). A pile of the stuff was ON TOP of the valve body, this not being visible until VB removed. In addition to cleaning everything, I would install an in-line filter in the fluid coolant line, easiest place seems to be close to the radiator. Particles of **** not only can CLOG fluid passages in the VB, but damage parts in the torque converter; then ya got REAL problems! imp

 

[Mamba42]

Ok, cool. Thanks for the information! I will have to look more closely into the solenoid issue. I'll try running the scanner with the engine hot and see what it tells me. If nothing, I'll look in the transmission pan to see if I can find and bronze chips. I think I'll also give the EGR replace a try too, because that will be a slightly less expensive and mechanically intensive fix. If that doesn't work, then I guess it's to looking into the transmission.

I'll keep you posted on what happens.

Thanks again, imp.

Jared

 

[whagen]

Similar issue with a 2004 explorer

I have a similar or same issue. Can't seem to figure out what is causing the low idle in gear. It's most noticeable when stopped in gear or when coming to a stop. The RPM looks to be 200 - 300 based on the tach. Plus you can feel the shake too.

Any other time the shifting seem fine, there is an occasional hard shift so a hesitation to down shift, but it's rare and similar to what I bought the truck new. Now that the weather is getting cooler, I can see that the tranny is not going in to 5th or locking or unlocking the torque converter till the tranny is warm (not really sure what is doesn't do till its warm, just can see the rpm is higher till I am a few miles down the road)

In neutral or park the idle is good.

Truck has 130K miles, nothing done to the tranny except a couple of solenoid pack changes early in it's life (before 10K miles, for very rough shifting into reverse).

Any suggestions on what to check and how to check to get me heading in the right direction?

 

[Mamba42]

Have you tried to pull any codes? If you could get a code, that'd go a long way in diagnosing what you need to do. Though, from what imp said, it sounds like you might have a solenoid issue. That'd be my guess since you're having shifting issues. But definitely put a scanner on it and see what kind of codes you've got if you haven't already done that.

 

[whagen]

There are no.lights. just ordered a scanner. So by the weekend I should know if there are any codes.

 

[imp]

I have a similar or same issue. Can't seem to figure out what is causing the low idle in gear. It's most noticeable when stopped in gear or when coming to a stop. The RPM looks to be 200 - 300 based on the tach. Plus you can feel the shake too.

Any other time the shifting seem fine, there is an occasional hard shift so a hesitation to down shift, but it's rare and similar to what I bought the truck new. Now that the weather is getting cooler, I can see that the tranny is not going in to 5th or locking or unlocking the torque converter till the tranny is warm (not really sure what is doesn't do till its warm, just can see the rpm is higher till I am a few miles down the road)

In neutral or park the idle is good.

Truck has 130K miles, nothing done to the tranny except a couple of solenoid pack changes early in it's life (before 10K miles, for very rough shifting into reverse).

Any suggestions on what to check and how to check to get me heading in the right direction?

Not same. Engaged TCC will KILL the engine upon slowing to a stop in any gear selected. Best guess I can make is the clutch is partially disengaged, or the TCC solenoid is only moving part-way through it's travel, due to mechanical problem, likely broken plunger guide bushing. imp

 

[Mamba42]

Alright, so I got the new EGR valve and pressure sensor in the mail today. I installed them both and it did not fix my problem. I still have no code. Imp, I did notice in your above post that the car always dies if its a TCC solenoid issue. My Ex does not actually stall (and hasn't actually stalled yet). It just is as if it is going to stall and my RPMs dip to about 450-550. I am stuck again, I was really hoping the EGR would fix the issue. The old one was very dirty though, so it was worth the change nonetheless.

I have not checked the spark plugs/coils yet. Would those maybe be a problem if the car only has idle issues in gear?

Thanks,

Jared

 

[Mamba42]

Actually I just took her for a spin and I think I've got a whole new issue. The transmission now is shifting very harshly and the car does not act like it's going to stall anymore. Very rough shift though when stopping and accelerating. Doesn't seem good. Any advice?

 

[imp]

Actually I just took her for a spin and I think I've got a whole new issue. The transmission now is shifting very harshly and the car does not act like it's going to stall anymore. Very rough shift though when stopping and accelerating. Doesn't seem good. Any advice?

PCM may have entered "limp home" mode, which allows driving the vehicle with serious defects at much reduced power levels, aimed at avoiding the "sitting along the roadside" syndrome.

Look for new trouble codes; there's bound to be something there, given the seriousness of the issue. imp

 

[whagen]

So I got a code reader, (BAFX Products (TM) - PIC18F2480 Bluetooth OBD2 scan tool) from amazon and used the paid version of Torque Pro (OBD 2 & Car) to look for codes and see if i code figure out anything.

P0506 -Powertrain - idle Control System RPM lower than expected
P1000 -Powertrain - OBD-II Monitor Testing Imcomplete
U2023 -external node malfunction (ABS related I think)
U2013 -Compass Module is not Responding
B2659 -Courtesy Switch Fault
B1352 -Ignition in Circuit Fault

As far as I can tell most of these are not much of a help. I just had to change the battery so some of them may have come from that or been in there for a while.

P0506 -doesn't really seem to point to anything just reporting that the idle is low which is what I know already.

P1000 -may be because the battery died.

U2023 -I had abs issues a while ago and had to replace the sensor on the master cylinder so it could be from that.

U2013, B2659, & B1352 I am thinking the battery issue.

So now I am thinking vacuum leak, now I just need to figure if this is the issue or that is a wild goose chase. tomorrow I will see if I can cap as many line to the intake that are not needed and see if I can see any change.

If anyone has a better idea or and idea as to where to look for a vacuum leak that would be great.

Till then I will try to clear the code and do some more driving and see if i can get any code to come up again and point me in a direction.

 

[whagen]

Fixed

Well after looking at a lot of messages in forums, it came down to putting my head under the hood and doing a little cleaning.

I cleaned the MAF sensor, but it looked perfectly clean, so I don't think this was the issue.

Then I took off the rest of of the intake, including the throttle body

Most of it was clean with the exception of the throttle body, it had a nice thick black build up. So with a can of CRC throttle body cleaner I went to work and cleaned it. (wish I took before and after pictures, but I didn't). After cleaning and letting it dry I cleaned the intake down stream of the throttle body best I could without taking it off. Put everything back one and it runs close to like new. I didn't drive it to much, but the hesitation is gone. It feels like there is a miss at idle, but not sure if its just the 130K miles making it feel that way or something else.

Also noticed the vacuum at idle was up a bit too, from 19.2 to 20.4 in-Hg. Not sure if this in the cleaning that did it or taking it apart and putting it back together.

This is all simple to do. You need a #20 torx for the MAF sensor, a 5/16 for the two hose clamps, and a 10mm for the throttle body. It would not hurt to have a throttle body gasket before incase yours gets messed up taking the throttle body off.

One last thing, I did not fine a definitive answer looking in forums or a parts list for the truck, but on a 2004 with the 4.6 V8 there is no IAC valve. The throttle body only has a TPS and the motor that moves the butter fly.

 

[Mamba42]

Just wanted to post an update on my issue. It is resolved now. I ended up just taking it to my mechanic because it was getting a little bit above my head.

What it ended up being was the my PCM was out of date. It needed to be re-flashed, and I don't think it had ever been updated before. The old programming was throwing everything out of whack. Now that it is updated, the car runs much better and transmission shifts much more smoothly. So, I guess if you have this problem you should make sure that your PCM is updated to the most current software. The PCM controls so much it will be worth it. It will be worth a shot before trying other things. I'm really glad it wasn't actual tranny issues!

Whagen, I think you're right about the '04 IAC. They don't have a separate IAC valve. That's a good deal you got it figured out though! Nice job