Transmission issue

[MikeC99017]

I apologize in advance if this is in the wrong place. I'm still learning my way around. I have an '02 Explorer with a V8. Last week I was driving and when slowing down to turn a corner or stop for a stop sign/light, the RPMs dropped and the engine died. I put it in neutral and it started right up, but continued to die at slow speeds when stopping or turning. I installed a new IAC valve and that seems to have cured the low idle/stalling problem, but now when I pull up to a stop light it seems like I have to press harder on the brake petal to stop. Then when I am stopped, the engine seems to lug a little bit like the car is trying to lunge forward. Now, in order to avoid the lunging when I'm stopped, I have to put the car in neutral as I'm coming to a stop and then put it back in drive when it's time to go. The car only has 77K miles on it and it's been great up to this point. If anyone has had a similar experience or knows what kind of repair might be needed, I would love to hear about it. Thanks in advance.

 

[SyberTiger]

I'm curious to know what RPMs you are seeing when you are at the stop light and the tranny is in neutral. Is it around 750 RPM?

It is possible that you got a bum IAC. It is also possible that you have the common problem with the cracked rubber elbow in the vacuum line. The rubber line elbow I speak of is the one that is on the hose runs under your IAC line. The elbow is within a inch of the IAC. See the following post: http://www.explorerforum.com/forums/showpost.php?p=1965554&postcount=11

 

[JoshMcMadMac]

It does sound like a vacuum problem. Check them for leaks or loose connections.

 

[MikeC99017]

The RPMs when I'm stopped in neutral are usually around 1000. When it starts jerking on me, the RPMs bounce between 500 and 1000. I took it in and had it checked for codes last night and there were none, so I will definitely checked for a vacuum leak. Thanks for the advice.

 

[JoshMcMadMac]

The RPMs when I'm stopped in neutral are usually around 1000. When it starts jerking on me, the RPMs bounce between 500 and 1000. I took it in and had it checked for codes last night and there were none, so I will definitely checked for a vacuum leak. Thanks for the advice.

Sounds like a good start. You will not have any codes (at least not current) without the check engine light being on.

 

[SyberTiger]

The RPMs when I'm stopped in neutral are usually around 1000. When it starts jerking on me, the RPMs bounce between 500 and 1000. I took it in and had it checked for codes last night and there were none, so I will definitely checked for a vacuum leak. Thanks for the advice.

Hmm, I'd recheck that IAC again too if you can't find any vacuum leaks. Maybe a bad IAC or maybe you don't have that hose on all the way. Can you please tell us where you bought your new IAC from and the manufacturer of the part?

 

[MikeC99017]

Hmm, I'd recheck that IAC again too if you can't find any vacuum leaks. Maybe a bad IAC or maybe you don't have that hose on all the way. Can you please tell us where you bought your new IAC from and the manufacturer of the part?

I bought it at Advance Auto Parts, and it was manufactured by BWD. I would have gone to the dealer, but it was a Sunday. Hopefully it's a decent part.

 

[SyberTiger]

I just changed out my IAC (a few days ago). I also bought the BWD product from AdvancedAuto as I'm on a road trip 500 miles away from home. It would appear that the BWD IAC gets good reviews. It is an American made in USA component.

 

[MikeC99017]

Quick update. Last night I removed the IAC valve and checked the hole into the throttle body. It was pretty dirty, so I scrubbed it clean with a tooth brush and carb. cleaner. I then checked the throttle body and noticed some buildup on the bottom of the throttle valve. I cleaned that up as best I could without removing it and then cleaned the MAF sensor again. I took it for a drive and while it's not completely back to normal, it's definitely a lot better. A mechanic friend of mine swears by the 44K engine treatment, so I put a can in and topped off the tank. We'll see if that helps. At least I now feel like I'm on the right track and I owe it all to this forum. Thanks again to everyone who responded.

 

[Exproblems]

Quick update. Last night I removed the IAC valve and checked the hole into the throttle body. It was pretty dirty, so I scrubbed it clean with a tooth brush and carb. cleaner. I then checked the throttle body and noticed some buildup on the bottom of the throttle valve. I cleaned that up as best I could without removing it and then cleaned the MAF sensor again. .

When you cleaned up the Throttle Body and the MAF sensor, did you clean them with Carb Cleaner or the correct Throttle Body and MAF sensor cleaners, sold in seperately named cans? According to everything I have read up on regarding cleaning the Throttle Body and MAF sensor in here, you are suppose to clean them with the specific type of cleaner made just for that device and purpose. Supposedly, you can damage them using other types of cleaners on them.

 

[MikeC99017]

I used MAF sensor cleaner on the MAF sensor and carb cleaner on the throttle body. I didn't see anything specifically made for throttle bodies at the store I went to, so I assumed the carb cleaner was the same thing. I will definitely switch to the throttle body cleaner if I need to do it again. Thanks for the advice.

 

[SyberTiger]

It still sounds like you don't have your Explorer idling perfectly. I would suggest the following.

1. Make sure none of your vacuum lines have leaks. Especially check out that elbow I previously mentioned. It is a notorious problem on Mustangs and Explorers. Even the mechanics at the dealerships have overlooked this problem causing the owners to spend hundreds of dollars.

2. Your IAC sounds like a recent installation. No way should it get dirty that quickly. You should consider changing out your PCV with a Motocraft one from your dealer. It is located on the passenger side valve cover. I've heard of bad/old PCVs clogging up IACs.

3. If #1 and #2 have been verified as fixed or not a problem then take your IAC back and tell AdvancedAuto it is defective. It has a one year warranty. Get a replacement.

 

[MikeC99017]

You're right about the idle. It drives and idles well until I pull up to a stop. When I first stop, the idle is about 1000 RPM. If I take off again within 1 or 2 seconds, the RPMs stay there and everything seems normal. If I sit for more than 2 or 3 seconds, though, the RPMs bounce down to 500 just for a split second and then settle at 700 or 800. I don't have any obvious hissing noises on any of my hoses, but I think I'm going to replace the PCV and the line with the elbow anyway. We'll see how that turns out, hopefully tonight. Thanks for the advice.

 

[MikeC99017]

Update:
I replaced the PCV valve and the vent hose with the infamous elbow, as well as the hose that attaches to the IAC. No improvement. I'm going to exchange the IAC for a new one after work today. If it is a vacuum leak elsewhere, is there a way to check that myself? When I listen for hissing sounds, I can't hear anything over the fan. Also, the car seems to idle normally after a cold start and does what I described above after it warms up.

By the way, the part number for the vent hose with the elbow is now KCV-240. The tag says it was revised in 7/05.

 

[SyberTiger]

Update:
I replaced the PCV valve and the vent hose with the infamous elbow, as well as the hose that attaches to the IAC. No improvement. I'm going to exchange the IAC for a new one after work today. If it is a vacuum leak elsewhere, is there a way to check that myself? When I listen for hissing sounds, I can't hear anything over the fan. Also, the car seems to idle normally after a cold start and does what I described above after it warms up.

By the way, the part number for the vent hose with the elbow is now KCV-240. The tag says it was revised in 7/05.

Well, if it makes you feel any better...The PCV probably was due to be changed as a maintenance item and the elbow has been such a notorious problem for those of us with this particular engine that you probably averted some anguish that would have shown up at a future date.

Regarding checking for vacuum leaks there is a technique using a small canister of propane or a spray can of ether (starting fluid). Ether is highly flammable so I prefer the former instead of the later.

Generally, the idea is to use a canister of propane/butane or similar like those you purchase at Home Depot that are hand held and used to braze/solder copper plumbing pipes in your home. You don't light the flame but rather you turn it on and hold it near the entire run of all your vacuum lines. If there is a vacuum line with a hole in it the suction will suck in the propane. The result will be that you will hear the engine speed increase just like you would expect if you sprayed starting fluid into the intake as the engine idles. Your vacuum line leak will be nearest where you are holding the propane to the vacuum line when the engine RPMs increase.

Do a search on this forum to find examples of this or other's experiences using this method.

 

[MikeC99017]

It still sounds like you don't have your Explorer idling perfectly. I would suggest the following.

1. Make sure none of your vacuum lines have leaks. Especially check out that elbow I previously mentioned. It is a notorious problem on Mustangs and Explorers. Even the mechanics at the dealerships have overlooked this problem causing the owners to spend hundreds of dollars.

2. Your IAC sounds like a recent installation. No way should it get dirty that quickly. You should consider changing out your PCV with a Motocraft one from your dealer. It is located on the passenger side valve cover. I've heard of bad/old PCVs clogging up IACs.

3. If #1 and #2 have been verified as fixed or not a problem then take your IAC back and tell AdvancedAuto it is defective. It has a one year warranty. Get a replacement.

SyberTiger, you are the man! I returned the after-market IAC and replaced it with a Motorcraft, and it is now purring like a kitten. The idle problem is completely gone, and it drives like it did when I bought it! And now I don't have to worry about the "infamous elbow." Thanks for all your help!!

 

[SyberTiger]

SyberTiger, you are the man! I returned the after-market IAC and replaced it with a Motorcraft, and it is now purring like a kitten. The idle problem is completely gone, and it drives like it did when I bought it! And now I don't have to worry about the "infamous elbow." Thanks for all your help!!

I glad it's finally fixed and your ordeal is over. Nothing more frustrating than a continual problem. Thank you for returning and giving updates along the way. It is very much appreciated by me and others that "final solutions" get posted by the OP with the exact nature of the fix. You'd be surprised at how many selfish people get on these types of forums for ideas on solutions but never come back and tell us what the fix was. For them it is "all about them" and getting the free knowledge from the good folks here but never offer feedback or remedies. Therefore, I SALUTE YOU!

BTW, can you double check to verify that your AdvancedAuto IAC was indeed a Borg-Warner (BWD) component that was Made in USA? I recently put one in my Explorer and it fixed my problem and thus far think of it as a quality part. Now I'm worried base on your feedback.

 

[MikeC99017]

I glad it's finally fixed and your ordeal is over. Nothing more frustrating than a continual problem. Thank you for returning and giving updates along the way. It is very much appreciated by me and others that "final solutions" get posted by the OP with the exact nature of the fix. You'd be surprised at how many selfish people get on these types of forums for ideas on solutions but never come back and tell us what the fix was. For them it is "all about them" and getting the free knowledge from the good folks here but never offer feedback or remedies. Therefore, I SALUTE YOU!

BTW, can you double check to verify that your AdvancedAuto IAC was indeed a Borg-Warner (BWD) component that was Made in USA? I recently put one in my Explorer and it fixed my problem and thus far think of it as a quality part. Now I'm worried base on your feedback.

Sorry for the delay. I was out of town and just got back last night. I can't say exactly where the part was manufactured, but the part I bought from Advance Auto was definitely a BWD. If the part you have is working well for you, I would guess that the one I had was defective. It never did work correctly, and as soon as I put the motorcraft part on my problem was solved. I hope it doesn't go bad on you, but if it does, the motorcraft IAC fixed my problem. Best of luck.