The engine maintenance light in my 2002 LS430 came on and I took it to my local 4 man repair shop. A new upper right side oxygen sensor was needed. A day later my wife drove the car on the freeway 60 miles (round trip) to an engagement and the next day I noticed in front, the right side of the engine under cover was hanging down a little.

I found a large triangle section (10”wide, 14” long) and the 3 screws in that section were missing (see 1st picture)! Up to 2 years ago I know the cover had never be off as I changed my oil and filter and it does not need to come off to do that. 8 months ago I had a shop change the timing belt, I assume they removed the cover. My local man said he removed it to change the oxygen sensor.

So what happened to the missing piece? Here is my take on this. From the 2nd picture it looks like the right edge was dragging on the pavement (more screws were removed to show this) while the left side was still slightly attached and wore it away (note the edge is parallel to the floor)! At 70 mph the wind could force it to stay down but if this is the case there had to be fewer screws toward the left side than when I looked at it, as the under cover was not hanging down far enough to reach the pavement (even at 70 mph). Of course, the repair guy has no idea how this happened as he said the cover was replaced properly. (Or could it have happened when the timing belt was changed?). How many miles would need to be driven to wear this much away?

 

The last guy to remove and replace it is responsible.

 

60 miles can do this. More on slow speed than hight as the wind under the car pushes it up. I say the 1st time it was not fixed properly, as sometimes mechanecsdont fix it properly tell after a road test. And sometimes they forget.
If it was as the 1st pic wen you notes that it I say the 1st mech did this. But it could be the second one as will when he did a road test.
Difecult to say.

 

Also, difficult to post.

OP, who knows when it was messed up but probably the second mechanic as, if I were him, and saw that it was not properly installed I'd bring it to your attention immediately so I wouldn't get blamed. It's a good idea to do a once-over, at least, when someone works on your car. Don't trust 'em!

 

The last person that worked under the car who had to reinstall the plastic shield is responsible for the damage and loss. Reinstalling the shield correctly is so easy. I would wonder what other short cuts and lack of professional care they took in working on the car.

 

There's a lot of screws (18 if I remember correctly) on that cover and the last guy that worked on your car could have gotten lazy or lost some of them. I have also noticed that the threaded plastic inserts that the screws go into have a habit of getting stripped or not holding it very tightly. That could be the problem too.

I have had the same thing as you on other cars and the solution was simply to buy another cover and new screws. Not sure what the price on this car will be but I can't see it being more that a couple hundred bucks. You could also go ghetto and buy some plastic sheet and screw it to the remaining cover. Or you could just leave it. Probably won't do much harm.

 

campisi

I do a walk around but did not think anyone could screw up the under cover by dragging it under the car. See my post at

https://www.clublexus.com/forums/ls-...ts-matter.html

 

No problems w1ayne - some people just automatically trust the dealer's mechanics to do things right. As you know, it just ain't so!
I'm in the same dilemma as you were on that linked post ... I need my TB replaced and I've got a decent mechainc (from reputation) that will do it (including the ancillary parts) for me for $450 labor. That is dirt cheap but I'm probably 80% sure I'm still going to do it myself. What a hassle but I if I do, in fact, do the work myself it's not so much to save money but for peace of mind. I've always done all of my own work on my cars but it's so tempting to throw $450 at the guy and not have to bust up my knuckles and make my back sore for a week. I don't have as many miles on me as you do but I am 54 and it's getting tougher and tougher to crawl around on a cold garage floor! thumbup:

 

I had mine come loose on me b4, sounded just like Primacy tires when going over cut concrete. I should have removed it then but it was like 2am on I-95 and only 15 minutes from the house. Oem replacement was $300 if I recall. Aftermarket from Ebay is like $60 but worthless IMO, you can roll it up and stick in your back pocket. If you did buy aftermarket, I would attach to original with some form of adhesive.

You could remove it but I would think it would affect drag, increasing fuel mileage and wind noise.. I did a search on Atlanta Craigslist for Lexus parts, some poster had a few ads for LS front bumpers. Emailed him and he sold me a engine splash guard/undercover for $50....

 

The '01 - '03 front lower engine cover is different than the '04 - '06 cover.

 

After taking the pan out and in multiple times, and screwing the bolts in slightly differently causes the holes to become slightly bigger, and therefore I think that's why it keeps falling out. I have a solution but IT"S TEMPORARY. Use zip ties. Zip them through the holes and then you will have a belly pan that no longer falls down randomly.

 

DealWithIt

See my solution at https://www.clublexus.com/forums/ls-...der-cover.html

 

That seems like a good idea to repair it. What size nut did you use and also where was a good place to find the screws? Mine's have been zip-tied up so I would fix this at the next oil change when I'm down there.

 

These 7 mm Confirmat Screws are all over ebay. The nut is just a spacer, its not use to tighten the screw. That is done with a 4 mm Allen wrench.
Do not get the 6.3 mm as they are 1/4 inch, the same size as the car comes with.