Rough Idle After Replacing Belt

[mosguy1844]

Hi. I have a 95 Explorer XLT 4X4 with the 4.0 OHV (eighth vin digit is an X). This morning I had the idler pulley that is next to the alternator seize and break off.

This also wrecked the drive belt and took a chunk out of the tensioner pulley.

I replaced the two pulleys and belt. Hooked the battery up again and drove the truck about five miles. It now has a rough idle with no CEL on. Under power it seems to do okay though I may not be noticing the vibration when I'm driving it as much as when it's sitting in the driveway.

This vehicle has 155,000 on it and has A/C if that helps. A few months ago the plugs and wires were replaced with a tuneup. Prior to the pulley breaking the truck ran great and idled fine. Perhaps I didn't allow enough time for the computer to "relearn" the idle.?.

I'm a college student without a lot of money so any insight into this problem would be greatly appreciated.

Thank you.

 

[96eb96]

Hi. I have a 95 Explorer XLT 4X4 with the 4.0 OHV (eighth vin digit is an X). This morning I had the idler pulley that is next to the alternator seize and break off.

This also wrecked the drive belt and took a chunk out of the tensioner pulley.

I replaced the two pulleys and belt. Hooked the battery up again and drove the truck about five miles. It now has a rough idle with no CEL on. Under power it seems to do okay though I may not be noticing the vibration when I'm driving it as much as when it's sitting in the driveway.

This vehicle has 155,000 on it and has A/C if that helps. A few months ago the plugs and wires were replaced with a tuneup. Prior to the pulley breaking the truck ran great and idled fine. Perhaps I didn't allow enough time for the computer to "relearn" the idle.?.

I'm a college student without a lot of money so any insight into this problem would be greatly appreciated.

Thank you.

The stock pulleys suddenly failing after 12-15 yrs are very common, and everyone should change them ASAP.

I'm wondering if you accidentally disconnected any air lines or wiring from the intake tube when you serviced the pulleys?

 

[Willard]

Make sure all the vacuum lines are still hooked up and not leaking, and make sure the intake tube is on all the way and not leaking either. That's what I would start with. If all that checks out, drive it for a week or so and see if it gets better as the computer re learns everything.

 

[mosguy1844]

The more I thought about it last night the more sense that makes. Either I knocked something loose or something else got damaged when the pulley blew off, rattled around, and rolled down the street

I will start checking all my lines as soon as the sun comes up here and post back. I hope that's all it is. I searched lots of rough idle threads here, but this just seemed odd that it ran great and then replacing the belt caused a rough idle (that part doesn't make sense).

Thank you for the replies. Also, why does this stuff always happen in January and never in July It's -2 here right now and no heated garage

 

[mosguy1844]

Today I checked all the vacuum hoses and checked for any other loose connections or damage. I'm not seeing anything that looks like it took a hit.

The pulley didn't fly around too much when it broke and hit the ground almost immediately.

I drove the truck today for about 18 miles, and while it seems to run good, and the tach says it's idling about 800 and stays fairly steady I still have the vibration.

I noticed when I got back that the fan has the better part of two blades broken. The blades are next to each other. The fan appears to be plastic and has about 8-10 blades. Could this be causing the vibration? Thanks again for any help.

Keith

 

[96eb96]

Today I checked all the vacuum hoses and checked for any other loose connections or damage. I'm not seeing anything that looks like it took a hit.

The pulley didn't fly around too much when it broke and hit the ground almost immediately.

I drove the truck today for about 18 miles, and while it seems to run good, and the tach says it's idling about 800 and stays fairly steady I still have the vibration.

I noticed when I got back that the fan has the better part of two blades broken. The blades are next to each other. The fan appears to be plastic and has about 8-10 blades. Could this be causing the vibration? Thanks again for any help.

Keith

Yep, it can also stress out the waterpump bearings. I would get that taken care of.

 

[mosguy1844]

Thank you. I'll try to track one down at the local boneyard tomorrow and see if it works.

 

[96eb96]

You may need a special fan removal tool rental from advance or autozone. Its just a custom wrench.

 

[mosguy1844]

*Solved* Rough Idle After Belt Replacement

I'd like to say a big thank you to you guys for helping me with this problem. I'd buy you a beer if I could.

I picked up a used fan from the junkyard today for $35 with the clutch and in nice shape. That did the trick. I thought I'd post my solution in case someone else finds themselves in the same predicament and sees this thread.

Good tip on the specialty tool. What I did was buy a cheap strap wrench and I took out the shorter nylon strap that came with it. I then took a longer piece of old fan belt and wedged it into the slot along with the wedge that was in the tool. Then I used a 1 1/2" crow's foot (skinny) that I had and used a vise grip on the end to turn the fan loose (a ratchet or big adjustable wrench doesn't fit).

The strap held the pulley and the crows foot turned the fan loose. Next time I'll buy the tool if I have the money. It would have been much easier.

Thank you so much again for the help.

 

[96eb96]

I'd like to say a big thank you to you guys for helping me with this problem. I'd buy you a beer if I could.

I picked up a used fan from the junkyard today for $35 with the clutch and in nice shape. That did the trick. I thought I'd post my solution in case someone else finds themselves in the same predicament and sees this thread.

Good tip on the specialty tool. What I did was buy a cheap strap wrench and I took out the shorter nylon strap that came with it. I then took a longer piece of old fan belt and wedged it into the slot along with the wedge that was in the tool. Then I used a 1 1/2" crow's foot (skinny) that I had and used a vise grip on the end to turn the fan loose (a ratchet or big adjustable wrench doesn't fit).

The strap held the pulley and the crows foot turned the fan loose. Next time I'll buy the tool if I have the money. It would have been much easier.

Thank you so much again for the help.

Glad to hear it worked out. The tool can be usually be rented at advance auto.

Moral of the story - change your old pulleys! They are spinning timebombs~!