Shuts off when shifted into reverse

[Jlloyd5774]

We just bought an 02 explorer with the 4.0 v6. Were having an intermittent problem with it shutting off when shifted into reverse. It this to me once, I started it up and put it reverse and it shut off, started it back up and there was no problem.

Didn't do this for about 3 weeks then last night my wife was backing in and when she put it reverse and turned the wheel she says battery and oil pressure lights came on and the steering was hard to turn, she said it was still running but I think it shut off due to the lights on the dash and hard steering. She said she turned the key off and started it back up then put it in reverse and tried it again and did the same thing and shut off, she started it back up a few mins later and back straight up and it was fine. When I got home I looked at it and tried to get it to do the same thing and it wouldn't do it.

I'm thinking this may have something to do with idle air control, maybe the valve needs pulled out and cleaned. There is no check engine light, I havnt checked for logged codes yet. If anyone has any advice or experience with this I'd like to here from you, thank you.

 

[Jlloyd5774]

Well no one has replied yet but I havnt got the explorer to shut off again yet. I just cleaned the maf sensor, the iac valve, and the throttle body just for preventative maintenance and I thought maybe it would help with the other problem.

When I first started it up the rpms raced up to around 2500, shut it off after a fews mins of running. disconnected the battery for about a min then started up again did the same thing. So I unplugged the iac and the rpms went down around 1200, then unplugged the maf and the engine shut off. Now it idles aaround 1200 in park and when in gear it drops to around 700 or so. Not sure what these explorers are supposed to idle at but 1200 seems like a lot it idled at around 750 before.

If anyone sees these posts and has any advice let me know, thanks.

 

[Duranged84]

It should idle somewhere around 750-800 rpms. I suggest checking the trans fluid, If your not familiar with how these idiotic designed fill/check plugs are set up, do a search on here. These transmissions are very picky about their fluid level, and can shift pretty normal even low, for a while... Ive seen them run several quarts low and still shift into every gear, although it will shorten the life quickly and start showing other signs, one being dieing when changing to reverse or drive. My trans had other problems, but a couple days before it shelled on me, I did notice it was dieing a lot when shifting in reverse out of nowhere, then acted fine till the day it just quit. Really suggest getting on the fluid level, if not fluid and filter change. Dont wait for it to get worse.

 

[yankeeshogun]

Greetings from sunny Portland Oregon. This happened to me many times on my 1994 Explorer when I was trying to shift from Overdrive or Drive into Park, until I realized that the bulky keys on my keychain were getting caught on the shift lever when it was moving upward, causing the ignition key to turn slightly backward, shutting off the engine. Now I take care to manage the keys on the keychain. You might experiment with this when in the safe confines of your garage or parking lot.

 

[Jlloyd5774]

Ok thanks for the advice guys. I plan on changing the fluid and filter soon anyway. Was trying to do it before it got cold but the cold is here lol. I don't remember if it idle this high before I cleaned the intake up but I didn't know if maybe the throttle or idle wasn't set right for some reason. I will try the trans fluid and filter next plus I plan on doing the fuel filter. All preventive maintenance that needs done anyway. Also maybe the rpms were so high due to the throttle body cleaner I sprayed in the intake but I thought that would of burnt off in the first few secs of starting not 10 mins later lol. The rpms seem to be around 1100 now in park and drop to like 800-900 in gear according to the vehicle tach. I will do some checking and maintenance and keep the posts updated. Thanks

 

[Duranged84]

While 1100 isnt real high, anything higher than normal idle is hard on internal trans parts when putting into gear. 1100 I dont think is high enough to cause damage any time soon, but have you tried getting any codes from it yet? May have pending codes that havent yet tripped the light.

 

[lincolnshibuya]

sounds like an IAC issue (search for engine stalling here), I have this issue on my v8 and it's hard to replicate until I noticed that the idle is not correct after disconnecting battery (I tried cleaning it) and it got worst. I've been cleaning it as part of my regular maintenance each year and I guess over time it just won't work properly anymore.

only Motorcraft IAC works on this truck (aftermarket doesn't work correctly)

 

[Jlloyd5774]

Well cel wasn't on until this past weekend. I checked the code and it was code P1506 idle air control over speed error. I cleared the code and the cel stayed out for now but it's still idling at 1100 in park so there's still a problem. Also sounds like the engine fan is on when I first start it but it goes off after awhile. I'm going to check a few other things and keep this post updated. I read if you disconnect the iac valve the rpms will drop and that means it's working, is this accurate? And if the rpms drop where should I go from there? If anyone has any other advice on troubleshooting this please let me know

 

[Jlloyd5774]

Well I sprayed throttle body cleaner around the intake and didn't find any leaks. I unplugged the iac valve and the rpms went from 1200 to around 950. Does this mean the iac valve is good?

 

[jeff4912]

Remove the IAC valve and then clean it thoroughly and put it back. That should correct it. My 2003 does the same thing and I clean the IAC about once a year.
I think I use throttle body spray cleaner and que tips.

 

[Jlloyd5774]

Well I already did that and after that it started idling high. I'm thinking it might be stuck open or something. I'm not exactly sure how they work but doesn't it open and close. Is there a way to test it before I replace it of should I just try to clean it again?

 

[jeff4912]

Check for a new one at Rockauto.com, they have good prices and service. Your IAC may just need replacing.
Looks like they have for $43 for OEM, and about $33 for aftermarket.

 

[Jlloyd5774]

Well I ended replacing the iac valve with a bwd brand from advance auto. I disconnected the battery then removed and replaced the iac valve I reused the old gasket. Hooked the battery back up and and started it up. It was still idling a little high for the first few seconds but it evened out to about 700 rpm in park.

So I'm guessing the iac valve was stuck ole just enough to keep the rpms up. I think I may have messed up the original when I cleaned it, may have let the throttle body cleaned sit I there to long. I'd say when you cleane them to be very gentle and not to use to harsh of a cleaning product

 

[lincolnshibuya]

Well I ended replacing the iac valve with a bwd brand from advance auto. I disconnected the battery then removed and replaced the iac valve I reused the old gasket. Hooked the battery back up and and started it up. It was still idling a little high for the first few seconds but it evened out to about 700 rpm in park.

So I'm guessing the iac valve was stuck ole just enough to keep the rpms up. I think I may have messed up the original when I cleaned it, may have let the throttle body cleaned sit I there to long. I'd say when you cleane them to be very gentle and not to use to harsh of a cleaning product

it's been proven here that aftermarket IAC doesn't work properly, only Motorcraft IAC works.

 

[Duranged84]

It sounds like the bwd he put in worked for him. Might not work exactly perfect but sounds to me like it's doing its job fine. Glad to hear you got positive results with it and not having it stay at 1100 rpms at idle.

I like to use oem as much as possible and yes some things anything other than oem don't work right but sometimes you have to make do with what you can get your hands on and sometimes that's close enough. A lot of cars idle a little high when first started in the cold. Plus the computer probably needed to relearn or adjust to the new part working right.

 

[Jlloyd5774]

I know I read the posts about the other bwd iac valve not working but this one seems to be working for now. Its been a few weeks and its been working properly so hopefully I just got lucky.