Monday, October 21, 2013

DIY Car Repair: Replacing the Window Regulator on a 1998 Pontiac Grand Prix Coupe

Seth and I were driving Blackie home from a wedding last weekend when I rolled up the passenger side window and heard an ominous "crunch" noise as it got to the top. I rolled the window down a couple inches and then tried to get it to go back up. No dice.

This was not a foreign problem for us as Blackie, our 1998 Pontiac Grand Prix GTP has the worst power windows in the world. Since I first bought her in 2008, we've replaced the driver side regulator twice and the passenger side once. The first time we took her in to our local mechanic who fixed both windows for $400. Ouch.

A couple years ago when the driver side window broke again, we took on the project ourselves. It was do-able, though a pain in the butt trying to glean together the necessary steps from cars on the Internet who looked similar, but not exactly like Blackie. At the time I believe it took me a good 3-4 hours of monkeying around before it was installed correctly. I hoped the second DIY would go a little smoother and I'm happy to say it did, though not without a couple hitches. So, I figured I'd pass on my knowledge in hopes that this might help someone else out in the future. Or at least help me remember what the heck I did the next time (and there will be a next time) Blackie's window regulator goes out.

First things first. I ordered the complete passenger side regulator assembly from Amazon. You can buy them without the motor, but I figured I might as well replace everything while I was at it. The model I ordered was the Dorman 741-809 for about $70. Seems like the model without the motor was around $40-50.

For this repair you'll need a Torx driver, a 10mm socket, and a flat head screwdriver. Needle nose pliers are optional. You'll probably want some painters tape as well.

If you can, start with the window rolled up all the way, or down just a couple inches. We'll be moving the window lower a little later but it'll be easier to adjust it to where it needs to be if you start it out higher. Remove the cover from the door handle by sliding it back towards the door opening. You'll need to pull out on the door handle and lift up on the skinny end of the cover to remove it.

Place a flat head screwdriver on the lower end of the window power switch and gently pry up. Slide the assembly back towards the door opening and lift out. Use a flat head screwdriver to release the tab on the switches and gently pull to disconnect.




Now use the flat head screwdriver to gently pry off the round plastic screw covers underneath the door grip. Use the Torx driver to remove the two screws. Don't worry if they fall inside the door as you'll be taking the panel off next.



Now for the scary part. Working around the edges, pull on the door panel to release it. This is actually really easy to do and nothing will break, it's just a little unnerving if you've never done it before. Once it comes off, work the door lamp through the opening and set the door panel to the side.

The door cavity will probably we covered by a sheet of plastic held on by tar. You don't need to remove the plastic completely, just peel it back starting from the side nearest the door opening until the door lever is uncovered. Let it rest inside the car on the floor.



There is a large block of foam inside the door cavity. Grab it from the top and pull towards you then up to lift it out. Now we are ready to start removing the old regulator.


Disconnect the motor by pressing on the grey tab with a flat head screwdriver and gently pulling down on the connector.


There are 4 screws holding the main part of the regulator to the door, 3 holding the motor assembly, and 2 connecting it to the actual window (these won't be visible if you window is up all the way). First remove the 4 main screws and 3 motor screws.


Next, reconnect the power window on the switch assembly. Roll down the window so that the 2 screws connected to the window assembly are easily accessible. The window will be almost half-way down.


My window is rolled up all the way in this pic, but use this same method to secure the window in the half-down state.

Using the painters tape (or masking tape), secure the window in place so it won't move. Now remove the 2 screws holding the window on. Gently work the old regulator assembly out of the door cavity.

Now to install the new regulator. Basically you're going to work in reverse. Place the new assembly into the door cavity. Install the 2 screws on the window assembly first and snug them down. Next loosely install one screw at the top and one screw in the bottom of the main regulator frame. Loosely install the remaining 2 screws.

Connect the pump switch and loosely install the 3 motor assembly screws. Now tighten all 7 screws: the 4 main screws and 3 motor screws. Test the window at this point and make sure it goes all the way down and all the way up. When I installed mine, the weather stripping on the outside of the window got caught behind the window and I had to shove it back into place with a screwdriver before the window would roll up all the way. Once you've tested the window, you can finish reassembling the door.

Make sure you put the foam block back in the door cavity then replace the plastic sheeting. Both times I've replaced the regulator, the kit has come with some new plastic clips for the panel. I'd recommend replacing any that look bad before putting the panel back on. Disconnect the window power switch and lift the door panel into place. Work the door light through the panel and then press the door clips around the edges to secure in place.

Carefully put the 2 Torx screws in to secure the door panel. Don't drop them inside or you'll have to take the panel off again. Press the plastic covers into place. Reconnect the power switch assembly and slide the door handle cover back on.

That's it! It's really not that scary of a project to tackle yourself. I know nothing about cars and only attempt the most basic of repairs. This was very doable and will save you well over $100 and a ton of hassle by doing it yourself. This time around the project took me 2 hours to do by myself and that included hunting down all the tools and working out the kinks in the process. If I had to go replace another regulator right this minute, I could probably do it in under an hour. So give it a shot!

1 comments:

Seth said...

Fantastic write-up... very well done.