Rev hang 93 4.0 V6 any ideas ???? | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

RADIOACTIVE_TOOL_SHED___

Well-Known Member
Joined
November 9, 2020
Messages
221
Reaction score
95
City, State
Greensboro north Carolina
Year, Model & Trim Level
1993 Ford explorer xlt
Hey everyone I have a 1993 Ford Explorer XLT 4.0, when I rev it slowly idles down I fixed most of the vacuum leaks but there's still one I think, it's starting to get on my nerves and I was wondering what I could do to fix it. Also it has a hard start problem after sitting truck has Brand new IAC valve and purge valve so I know it's neither of those, I ran the truck out of gas a couple of times because the gas gauge doesn't work I'm gonna be replacing the fuel pump and sending unit in the near future any ideas on what would be causing any of these problems ? Thanks in advance
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Have you yet sorted out why your check engine light was never illuminating?
 












when I rev it slowly idles down
Could you provide a general time rate, more detail?
I fixed most of the vacuum leaks but there's still one I think
What makes you think this?

I'm gonna be replacing the fuel pump and sending unit in the near future
Did you test fuel pressure? Did you check fuse #17 (think that's for fuel guage)? Consider inline fuel filter replacement first if you are going to replace without thorough troubleshooting.
I don't recall seeing mileage posted in your threads.


Having no CEL available, have you run a self test/ checked for trouble codes at the connector? In another thread you mentioned water entry on passenger side. Should verify that the PCM wasn't effected by this.
 






Could you provide a general time rate, more detail?

What makes you think this?


Did you test fuel pressure? Did you check fuse #17 (think that's for fuel guage)? Consider inline fuel filter replacement first if you are going to replace without thorough troubleshooting.
I don't recall seeing mileage posted in your threads.


Having no CEL available, have you run a self test/ checked for trouble codes at the connector? In another thread you mentioned water entry on passenger side. Should verify that the PCM wasn't effected by this.
PCM Should be good, I checked fuse #17 and that was good I gotta new fuel filter and pump assembly and it could be just me but I think I can hear air escaping when I turn the truck off with the hood open (can't always here it ) and the rev hangs for about 3 to 4 seconds then it goes down too 1000 RPMS and then back down to 800 my TPS looks pretty dirty could this be causing the rev hang and hard starts ?
 






PCM Should be good, I checked fuse #17 and that was good I gotta new fuel filter and pump assembly and it could be just me but I think I can hear air escaping when I turn the truck off with the hood open (can't always here it ) and the rev hangs for about 3 to 4 seconds then it goes down too 1000 RPMS and then back down to 800 my TPS looks pretty dirty could this be causing the rev hang and hard starts ?
And no I haven't checked for trouble codes I believe it's possible to check with a paper clip ?
 






PCM Should be good
And no I haven't checked for trouble codes I believe it's possible to check with a paper clip ?
Pages advising on how to pull from good PCM


I think I can hear air escaping when I turn the truck off
Air would not be escaping , but could be in-rushing to leak in vacuum reservoir I suppose.


TPS looks pretty dirty could this be causing the rev hang and hard starts ?
external dirt on your TPS doesn't indicate anything about it's functionality. If you suspect it, visually inspect connctor pins, and multimeter probe test is very straightforward.

Until you are certain you have ruled out vacuum leak though, I suggest letting that be your point of focus (after trouble code test). Has your troubleshooting involved a way to apply and measure vacuum persistence such as this American Educational Hand Operated Vacuum Pump with Gauge: Science Lab Pumps: Amazon.com: Industrial & Scientific ?
 






Pages advising on how to pull from good PCM



Air would not be escaping , but could be in-rushing to leak in vacuum reservoir I suppose.



external dirt on your TPS doesn't indicate anything about it's functionality. If you suspect it, visually inspect connctor pins, and multimeter probe test is very straightforward.

Until you are certain you have ruled out vacuum leak though, I suggest letting that be your point of focus (after trouble code test). Has your troubleshooting involved a way to apply and measure vacuum persistence such as this American Educational Hand Operated Vacuum Pump with Gauge: Science Lab Pumps: Amazon.com: Industrial & Scientific ?
The only tests I have done on the vacuum lines was about 10 minutes ago I sprayed most of the easy accessible lines with sopy water I listened for a idle change nothing it started easy today and yesterday but once it warms up it idles perfectly I'm gonna run down and get a new TPS sensor later and see if that changes anything oh and I'll try to pull code's from the system if this new tps sensor doesn't fix it
 






I had a similar issue a couple years ago, thought it was TPS but tested it with a meter and it was fine.
Ended up cleaning the MAF and that fixed it
FWIW
 






I had a similar issue a couple years ago, thought it was TPS but tested it with a meter and it was fine.
Ended up cleaning the MAF and that fixed it
FWIW
I'll try that thank you for the info 😃
 


















Where?
 












Back
Top