'94, exhaust smell, running rich? (1 Viewer)

[MTrun]

Reaching out to the community for a little help. My 1994 has always has a bit of an exhaust smell (like a lawnmower, not sweet). Reading through the forums I see some starting points but would love your thoughts before I start ripping things apart and drop the money for a new exhaust system:

-1994 FZJ80
- Exhaust smell in cabin
- Engine recebtly overhauled, new block, all gaskets, machined head (no change to smell before/after)
- Cats have been removed (previous owner)
- Both O2 sensors recently replaced (no CEL)
- Charcoal cannister replaced
- Smell goes away when cabin air vents are blowing outside air in (or at least isn't coming from them)
- Exhaust is clear at startup, but within a minute starts become more visibly whitish which I suspect may be excess fuel Vapor, and smells more.

I will start saving for a new exhaust system, but have a hunch something else could be off causing the engine to run rich. Being a '94 it also has that extra egr equipment that is still original.

 

[Fj80oregon]

Not sure about your cruisers mechanical condition. But a well known area that lets engine bay smells in is the steering column dust shield/gasket. They wear out and eventually leave a large unsealed hole around the column.

 

[george_tlc]

- Cats have been removed (previous owner)

Will siginificantly smell like pre-cat vehicles of the 'olden days'.

cheers,
george.

 

[BILT4ME]

Reaching out to the community for a little help. My 1994 has always has a bit of an exhaust smell (like a lawnmower, not sweet). Reading through the forums I see some starting points but would love your thoughts before I start ripping things apart and drop the money for a new exhaust system:

-1994 FZJ80
- Exhaust smell in cabin
- Engine recebtly overhauled, new block, all gaskets, machined head (no change to smell before/after)
- Cats have been removed (previous owner)
- Both O2 sensors recently replaced (no CEL)
- Charcoal cannister replaced
- Smell goes away when cabin air vents are blowing outside air in (or at least isn't coming from them)
- Exhaust is clear at startup, but within a minute starts become more visibly whitish which I suspect may be excess fuel Vapor, and smells more.

I will start saving for a new exhaust system, but have a hunch something else could be off causing the engine to run rich. Being a '94 it also has that extra egr equipment that is still original.

The fact that you have no cats will cause the exhaust to smell much more "rich" and heavy. That's the purpose of cats....to burn off the excess fuel and stuff to reduce emissions.

And look for exhaust leaks and replace the boot on the steering column like @Fj80oregon stated.

Depending on how and where the exhaust terminates at the rear of the truck, you may be getting exhaust fumes into the cabin through holes in the floor or fenders or whatever in the rear. (rust holes) The exhaust tip should be just outside the rear fender or bumper. If it's under the truck, then you're getting exhaust inside.

 

[12bit]

My truck had a pretty big hole rusted through in the rear quarter panel near the tailpipe. It was hidden by the rear bumper tupperware. I have since patched it up, but it was definitely letting fumes in the cab.

 

[MTrun]

Not sure about your cruisers mechanical condition. But a well known area that lets engine bay smells in is the steering column dust shield/gasket. They wear out and eventually leave a large unsealed hole around the column.

Good call! I did replace that one

 

[MTrun]

The fact that you have no cats will cause the exhaust to smell much more "rich" and heavy. That's the purpose of cats....to burn off the excess fuel and stuff to reduce emissions.

And look for exhaust leaks and replace the boot on the steering column like @Fj80oregon stated.

Depending on how and where the exhaust terminates at the rear of the truck, you may be getting exhaust fumes into the cabin through holes in the floor or fenders or whatever in the rear. (rust holes) The exhaust tip should be just outside the rear fender or bumper. If it's under the truck, then you're getting exhaust inside.

This already is likely part of the problem. It is definitely under the truck

 

[MTrun]

My truck had a pretty big hole rusted through in the rear quarter panel near the tailpipe. It was hidden by the rear bumper tupperware. I have since patched it up, but it was definitely letting fumes in the cab.

Thanks 12bit - will definitely take a look!

 

[mudgudgeon]

I'll second or third what others have said.

Steering column seal,
open holes in the floor, eg, missing grommets in the floor, inner guards, quarter panel, missing 3rd row seat bolts etc have all been responsible for exhaust odors in my cruisers.
Also, the rubber boot around shifters is one that's let smell in on vehicles I've owned in the past ( not just cruisers)

 

[MTrun]

You guys are rock stars. My exhaust is definitely cut off, check out the first photo.

I do still think it's running richer than it should be...BUT first you had me double checking for holes on the underside I was looking for every tiny nook or cranny that could be creating an entrance point for exhaust, and that's when looking back from a different angle in the far back passenger corner I saw this... (2nd photo)

I put a temporary patch on it until I can order the cover...and will let you know!

 

[BILT4ME]

You guys are rock stars. My exhaust is definitely cut off, check out the first photo.

I do still think it's running richer than it should be...BUT first you had me double checking for holes on the underside I was looking for every tiny nook or cranny that could be creating an entrance point for exhaust, and that's when looking back from a different angle in the far back passenger corner I saw this... (2nd photo)

I put a temporary patch on it until I can order the cover...and will let you know!

View attachment 3268070

View attachment 3268073

Having the short exhaust and that hole, that's why you get the exhaust smell on anything other than fresh air setting.

Don't sit in the drive through with the engine running until you at least get that hole covered.

 

[MTrun]

Having the short exhaust and that hole, that's why you get the exhaust smell on anything other than fresh air setting.

Don't sit in the drive through with the engine running until you at least get that hole covered.

Good call BILT4ME. Its repaired with magical duct tape now (drastic improvement), will make it official with the actual part on my next order!

 

[yoTyM]

Good call BILT4ME. Its repaired with magical duct tape now (drastic improvement), will make it official with the actual part on my next order!

Do you know what the part number for this hole cover is?

 

[CharlieS]

I'm with the group that blames it on the absence of cats.

I'd recommend also checking the rubber boot around the shift linkage under the console. Mine was failed and let a ton of heat and air into the cabin.

Are you getting a code 26 on the obd? If you were running rich, I'd expect that.

 

[MTrun]

Do you know what the part number for this hole cover is?

Sorry for the delay -- just now saw your question. The back service hole cover is Toyota part number: 6474560010 should run $5-$10.

 

[yoTyM]

Sorry for the delay -- just now saw your question. The back service hole cover is Toyota part number: 6474560010 should run $5-$10.

Much appreciated, part on order. This was definitely the source of the issue for me as the plug directly behind my exhaust was missing.

 

[Broski]

You guys are rock stars. My exhaust is definitely cut off, check out the first photo.

I do still think it's running richer than it should be...BUT first you had me double checking for holes on the underside I was looking for every tiny nook or cranny that could be creating an entrance point for exhaust, and that's when looking back from a different angle in the far back passenger corner I saw this... (2nd photo)

I put a temporary patch on it until I can order the cover...and will let you know!

View attachment 3268070

View attachment 3268073

My exhaust is cut off in the same place. it's a 94 but have both cat's in place and my plug is not missing. I have never had exhaust smells in the cabin unless I have the windows down and I'm warming up the truck in the garage.
Running with out the Cats definitely make the exhaust smell much worse and with out any performance gains !!

 

[MTrun]

Much appreciated, part on order. This was definitely the source of the issue for me as the plug directly behind my exhaust was missing.

Any time. Glad you found the problem hopefully it is a very cheap and simple fix for you as well!