Floor board buckled behind driver seat

PDACPA · PDACPA's Garage

I was moving my drivers seat looking for the box to put in a chip and found that the floor behind the drivers seat closest to the door was buckled.

I had recently lifted the car with the jack and this appears to be inline with where the jack inserts into the side of the car (I used the OEM jack to lift the car).

What is the floor made of? Should I be concerned that it its is sort of bent up? Should I not use the factory jack?

Joeaksa · 08:20 AM

This usually happens when someone at a garage uses a lift and has no idea where the lift points are on a 911. Lifting it on the floor area causes it to deform. Not unusual to see on some cars and most people just stand on the floor inside the car and push it back down and learn to be more careful where they take the car for maintenance.

If you actually bent your floorpan using the factory jack then it would mean that the floorpan was not able to support the surrounding area, which I really doubt unless the car is completely rusted out in this area. On some of the older cars I have seen (pre-76), the jacking point rusts out before the floorpan goes, so I doubt that this is the case with your car.

More important if this has happened is to get under the car and really inspect both the A/C lines on one side and the oil cooler lines on the other side. If someone has jacked the car up and damaged the floorpan, they also may have pinched the lines running fore and aft. My oil lines were pinched this way and replaced by the garage last year.

Joe

pwd72s · 05-22-2002, 08:36 AM

I agree. More likely a shop lift somewhere caused this dent. It happened to me once. I just tapped things back straight with the use of a length of 2X4 and a heavy hammer. I wrapped the 2x4 end in rags to eliminate any marking of the floor panel. It worked well. And I never returned to that shop again.

PDACPA · PDACPA's Garage

Thanks Joe. You eased my concern. I thought I had done it when I jacked up the car.

But I will look as my AC is not blowing cold air (going into the shop as soon as my exhaust arrives) so maybe the lines are pinched there.

The car is at home, but I think I did see some small amount of rust on the inside of the floor board so I will have to investigate it tonight.

Formerly Steve Wilkinson · 05-22-2002, 08:49 AM

I used a heavy rubber hammer when this happened to my car. It wasn't bad, just dented the floorboard upward a bit, and a few whacks with the hammer totally eliminated it.

Stephan

Superman · 05-22-2002, 09:17 AM

I used my foot.

PDACPA · PDACPA's Garage

I stood on it last night but it did not move. I will try the padded 2x4 but I am worried if there is a tad of rust there. I think I saw some.

Car is an 89 and I have owned it since 95 in Florida. So I am concerened if there is rust there and how to repair it if there is.

Don Wohlfarth · 05-22-2002, 10:31 AM

There's also the possibility that the floor board was bent before you bought the car and the rust you see has been there a while as well. The inside floor board is pretty unusual place for a car to start rusting.

The rust probably started when water got into the car during a shower from having the window or sunroof open.
Of course it could also be that the floor board has been punctured from the outside inward and every time you drive thru a puddle water comes in thru the hole.
99% of the time it's no big deal, pound the floor level, and start worrying why the chip didn't make an additional 47 hp as advertised.

PDACPA · PDACPA's Garage

Don

My guess is that it was bent from a jack misplaced and I had not noticed it due to the rear carpet and mat. I am going to pound it back down and see if there is a way water can get in from under it.

As for the chip, as long as I get some increase I am happy. Any recommendations?

Joeaksa · 12:45 PM

After you do pound the floor back down it will probably cause cracks in the undercoating. If you live or drive somewhere that uses salt on the roads I would think about checking the underside of the car before winter hits again and possibly re-applying a bit to cover any cracks that occured to protect the underside.

Re the chip. I have one in my car and took it out to troubleshoot my motor cutting out recently. Was not the chip (cyl head temp sensor, update yours if its not been done already!) but after putting the stock chip back in my mileage went up greatly. Was getting 350 to 375 miles per tank with mixed driving before, now am getting 425 to 450 per tank! Now that gas is above a buck, thats not small change.

Driveability was not affected that much going back to stock. I am now going to swap out the unit (I have an extra DME computer, so the whole thing takes 10 minutes to change) and put the performance chip back in the car for normal driving and when going on a trip reinstall the stock unit in the car. The performance chip seems to have a bit more power than normal but nothing exciting.

Pls be sure you know where your chip came from and what its limitations are. Many chip "tweakers" raise the rev limit from stock of 6200 to a bit higher to make it seem that it has more power. Pls be aware that operation at or above 7200 has been known to result in broken rod bolts, and the complete loss of the motor. Make sure your chip has a max rpm limit that is not too close to 7200 or beware that you are really pushing the limits.

Joe

PDACPA · PDACPA's Garage

cyl head sensor....where on the car is it and is it hard to replace?

do you just have to remember your rev limit or does the chip allow the car to rev higher

Joeaksa · 05-22-2002, 03:57 PM

Its screwed into the left hand forward cylinder head. Its a PITA to get to, even with the right tools! You really need to grind away the side of a deep well socket to tighten the new sensor in the head and even then its not easy.

The rev limit is controled by the DME computer and the chip that is stuck on its board. You can "adjust" this limit by reprogramming the chip but its not for the faint of heart. When done incorrectly, the rpm limit will be the rod bolts breaking, not the chip and the computers cutting off the fuel at a specified speed.

Below are Pelican tech articles on both installing your new chip and replacing the cyl head sensor.

Joe

http://www.pelicanparts.com/techarticles/911_motronic_chip/911_motronic_chip2.htm

http://www.pelicanparts.com/techarticles/911_cyl_head_temp_sensor/911_cyl_head_temp_sensor.htm