1997 Explorer idle problems
Thread Starter
|
New User
Joined: May 2007
Posts: 3
Likes: 0
1997 Explorer idle problems
4.0L engine
The problem started after I went out shut the car off, then when i went to start it again, it was running rough and the idle was up and down.
I found that I had a dead spark plug, so that cured the rough running part, but the idle was still not right.
When I first start the car when its cold, it revs up to about 2000 Rpm for 1 min or so, then gradually drops down to idle, when I hit the throttle, it revs up, but it slowly comes down to idle.
When I am driving down the road, I can cruise at 40 kmph without touching the gas.
I read that the Idle control valve is a common problem, so I was able to get a supossidly good used one and it didnt change a thing. also i was thinking vacuum leak, so I used accetylene and found no leaks. Also though there were a few spots I could not get to.
Any suggestions would be very much appreciated.
The problem started after I went out shut the car off, then when i went to start it again, it was running rough and the idle was up and down.
I found that I had a dead spark plug, so that cured the rough running part, but the idle was still not right.
When I first start the car when its cold, it revs up to about 2000 Rpm for 1 min or so, then gradually drops down to idle, when I hit the throttle, it revs up, but it slowly comes down to idle.
When I am driving down the road, I can cruise at 40 kmph without touching the gas.
I read that the Idle control valve is a common problem, so I was able to get a supossidly good used one and it didnt change a thing. also i was thinking vacuum leak, so I used accetylene and found no leaks. Also though there were a few spots I could not get to.
Any suggestions would be very much appreciated.
Senior User
Joined: Mar 2007
Posts: 108
Likes: 1
I had the same problem with a 93 T-bird. Took off the IAC idle control valve and it was burned up. Replaced it and things went back to normal, but not completely.
Idles fine at 750 rpm, I set the engine timming at 10 degrees TDC. That helps a lot.
I used the old gasket, thats the mistake. There are no short cuts.
The valve was $95.90 local of $71.76 on-line, but shipping will add $9.00
What does the old one look like. The inside is plastic.
Cleaning the valves isn't reccomended.
Eventually most of the senors go to sensor heaven it doesn't hurt to replace them as needed. Be sure and use a "new gasket".
A dead plug?
Idles fine at 750 rpm, I set the engine timming at 10 degrees TDC. That helps a lot.
I used the old gasket, thats the mistake. There are no short cuts.
The valve was $95.90 local of $71.76 on-line, but shipping will add $9.00
What does the old one look like. The inside is plastic.
Cleaning the valves isn't reccomended.
Eventually most of the senors go to sensor heaven it doesn't hurt to replace them as needed. Be sure and use a "new gasket".
A dead plug?
Thread Starter
|
New User
Joined: May 2007
Posts: 3
Likes: 0
After you replaced the idle motor, what was it doing???
and did you totally fix the problem by replacing the gasket?
the dead spark plug caused a misfire, after replacing it, the engine ran smooth, but still had the idle problem.
and did you totally fix the problem by replacing the gasket?
the dead spark plug caused a misfire, after replacing it, the engine ran smooth, but still had the idle problem.
Cargo Master
Joined: Aug 2003
Posts: 3,263
Likes: 92
From: BC Canada
Originally Posted by leafman13
4.0L engine
When I first start the car when its cold, it revs up to about 2000 Rpm for 1 min or so, then gradually drops down to idle, when I hit the throttle, it revs up, but it slowly comes down to idle.
When I am driving down the road, I can cruise at 40 kmph without touching the gas.
Any suggestions would be very much appreciated.
When I first start the car when its cold, it revs up to about 2000 Rpm for 1 min or so, then gradually drops down to idle, when I hit the throttle, it revs up, but it slowly comes down to idle.
When I am driving down the road, I can cruise at 40 kmph without touching the gas.
Any suggestions would be very much appreciated.
I am of the mind to pull/test the injectors, might be one leaking/sticking.
Senior User
Joined: Mar 2007
Posts: 108
Likes: 1
Originally Posted by leafman13
After you replaced the idle motor, what was it doing???
and did you totally fix the problem by replacing the gasket?
the dead spark plug caused a misfire, after replacing it, the engine ran smooth, but still had the idle problem.
and did you totally fix the problem by replacing the gasket?
the dead spark plug caused a misfire, after replacing it, the engine ran smooth, but still had the idle problem.
It fixed my car. The problem started with a blown head gasket, which lead to the 0.2 sensors going bad, and the IAC getting too hot.
After two new head gaskets the car ran bad, till I got the 02 senors and the IAC.
Before I installed the new IAC the car started at 2000 rpm, dropped to 500 rpm but when you stepped on the gas the engine rev'd to 3000 and stayed there for a while and then gradually it dropped to 2000 and then 1000 and then to 500 rpm.
On this car the new 02 senors and the IAC and setting the timing to 10 degrees tdc made a world of difference.
It seems one thing leads to another. The good thing about Fords is they circle the problem.
Thread Starter
|
New User
Joined: May 2007
Posts: 3
Likes: 0
My IAC looked in good condition, and I found link on how to check it out by measuring resistance and my IAC is ok. When I step on the gas, it revs up to 2000 rpm, then gradually drops to idle. I measured the voltage to the IAC and it increses as well, so I know it is being told to increase RPM, so it is not the IAC.
I need to do some wire tracing to see where the signal comes from.
I need to do some wire tracing to see where the signal comes from.
Senior User
Joined: Mar 2007
Posts: 108
Likes: 1
Originally Posted by leafman13
My IAC looked in good condition, and I found link on how to check it out by measuring resistance and my IAC is ok. When I step on the gas, it revs up to 2000 rpm, then gradually drops to idle. I measured the voltage to the IAC and it increses as well, so I know it is being told to increase RPM, so it is not the IAC.
I need to do some wire tracing to see where the signal comes from.
I need to do some wire tracing to see where the signal comes from.
Trending Topics
Senior User
Joined: Apr 2007
Posts: 112
Likes: 0
remove the air inlet tube hold the throttle wide open and look at the throttle plate and around the bore were the plate sits when at idle. If it is all black and sooted up take a tooth brush and carb and choke cleaner scrub both the plate and bore clean. then remove the ground cable from the bat and hold it on the pos bat cable for 30 sec this will clear the keep alive memory ( ilde/ fuel control)and reset the pcm .good luck
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
theonefordfan
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
6
Mar 8, 2015 09:47 AM
wackercattle
6.0L Power Stroke Diesel
8
Feb 23, 2015 10:00 PM
captcaseyb
1987 - 1996 F150 & Larger F-Series Trucks
2
Dec 21, 2014 12:07 PM