Bronco Forum - Full Size Ford Bronco Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
604 Posts
Discussion Starter #1
Ok, I got the Bronco running again after sitting for 2 to 3 months and as I drove it around Sunday I remembered another small issue that I have not figured out yet, so I am here to look for advice.

When driving there apparently is some sort of fumes or exhaust or something that is coming into the cab. As a result of this I end up with a slight headache and stink of exhaust or whatever. This occurs whether the windows are open or closed.
I do not notice any smoke or exhaust coming from under the hood or out the exhaust (which is a dual out the sides) when driving or when the truck is idling in the driveway.

Anyone have any ideas or anything I can check. I am tempted to go buy a smoke and carbon monoxide detector (the kind you would typically put in your home) and put it in the truck and see if it goes off.

Any help would be appreciated.
 

·
Call an amberlamps!
Joined
·
1,349 Posts
I had a truck that did that to me as well. I got sick and passed out from the CO2. Not safe man... that shit can kill ya.

Check out the entire exhaust system from headers back, all connections and everything even a small leak in the wrong place can pump fumes into the cab.
 

·
Satyr of the Midwest
Joined
·
17,734 Posts
A leaking tailgate seal can easily allow exhaust fumes to enter. Even the tailgate service cover can allow fumes to enter a little, since the bottom of the tailgate is vented for water to drain.
 

·
Registered
Joined
·
4,684 Posts
CO will kill you. Get that fixed right away. If it's bad enough to give you a headache, it's killing you.
 

·
Registered
Joined
·
604 Posts
Discussion Starter #5
Thanks for the input guys. Please be advised that this is not my daily driver and also not being driven at all (except for a drive on Sunday for about 5 minutes) until this issue is resolved.
 

·
Registered
Joined
·
300 Posts
I posted the same thing like a month ago and got no real answer. One thing that has helped is not driving with the rear window down. Its sucks the exhaust right into the cabin. On a cold night I looked under my truck with the engine on with a flashlight and could not find one leak. I don't know, I factor part of it from being an old vehicle. The rear tailgate seals seems like it might help to, anything to keep the exhaust from being sucked back inside. Good luck and don't die...even though a death in a bronco would be a noble death.
 

·
Explorer driving
Joined
·
4,192 Posts
There's a crossover tube at the very back of the engine, on my 351 there is, and it has rusted thru and it allows some fumes to enter the cab I assume just thru the ductwork. I don't recall the name of it, but I do know that it is a PITA to remove.
 

·
Registered
Joined
·
604 Posts
Discussion Starter #8
I posted the same thing like a month ago and got no real answer. One thing that has helped is not driving with the rear window down. Its sucks the exhaust right into the cabin. On a cold night I looked under my truck with the engine on with a flashlight and could not find one leak. I don't know, I factor part of it from being an old vehicle. The rear tailgate seals seems like it might help to, anything to keep the exhaust from being sucked back inside. Good luck and don't die...even though a death in a bronco would be a noble death.
Pretty damn funny....was that last part a quote from Legends of the Fall?

For the record, the rear window is usually not down and has not been down since this smell.
Now that I have been thinking about this morning, I do recall a "mod" that I did that may have some effect on this.
My Bronco had the spare tire mounted inside. I took the mounting out including the nut/bolt or whatever was in the rear floorboard or rear bed of truck.
I think I recall making the hole bigger and running my CB Antenna wire from the front of truck to the back to my newly "modded" access hole for easy and convenient hook up to the CB antenna mounted on the passenger side rear bumper. I wonder if exhaust is coming back in through that hole???
I will have to check that out and try to refresh my memory as to where this is located as well as if I sealed it up somehow....
 

·
Premium Member
Joined
·
9,984 Posts
mobronco93:
That cross-over tube which bolts to the back of the cylinder heads is part of your emission system called Thermactor Air System, it could just be the check valve on top but visual is the only way to know for sure but you'll need to pull it off. There are numerous threads on this.

If you don't fix that you will do serious damage to the emissions system & heads $$$$$$$$$$$$$$$.

I know trust me!

Good Luck ~ :thumbup
 

·
Registered
Joined
·
104 Posts
I go with what mobronco93 and jkossarides said: thermactor crossover.

I had a '91 that would stink up the cab with exhaust. turns out that the crossover tube was actually had holes in it from rust and was sending exhaust fumes into the cab through the vents.

I saw a thread with pics of this area behind the engine once posted by a forum member that actually removed the body from the chassis.

I never changed mine. Ended up giving that bronco away.
 

·
Premium Member
Joined
·
9,984 Posts
In miseroth's case it more then likely to be the tailgate the way I read it , but yes when my check valve had burned thru on the TAS it would come in thru the vents because it's right there at the back of the motor.

Now I have a dead cylinder on #2 probably due to that because it took me a while to figure it out very frustrating but I'm planning a 302 rebuild anyway so NBD at this point.

Visual inspection is always best if there's any question when you have a problem that's in a difficult location.

:thumbup
 

·
Registered
Joined
·
604 Posts
Discussion Starter #13
In my Bronco the problem was the tailgate seal. Replaced it and no more stink.
I have not looked into the process of replacing the tailgate seal, but am wondering (1) is it a PITA type job to do yourself and (2) where is the best place to pick up a new tailgate seal?

Thanks again!!
 

·
Registered
Joined
·
904 Posts
I saw a thread on this a little while ago and one of the ideas thrown out there was acutally a VERY good one, and completely unrelated to C0 (carbon monoxide, not C02). If the interior has ever been wet or damp, there is a distinct possibility that your bronco has a mold problem. Some people arent bothered by mold, i know some that have been hospitalized because of it, and i myself get pretty lethargic if i breathe in mold spores. Makes me glad my bronco doesnt have carpeting anymore...


just a thought.

And mine also gets a good deal of exhaust smell in it. Its never made me tired or feel sick,, but i am always aware of it. Ofcourse, mine also has a 12"x12" hole in the bed for fuel pump access, no tailpipe, and a couple rust spots on the rear wheel wells... just another reason to go topless in my book.
 
1 - 14 of 14 Posts
Top