Hi guys i have a problem i had my cats removed and had a straight pipe put in its place for some reason the car smells like exhaust is leaking in. I dont know where its coming from i had the straight pipe checked to make sure the weld was clean all the way but its all good. I dont know where its coming from it only smells when im driving so its hard to check where its coming from.
Thanks for any advice

they put the tube back on the exhaust that went to the air pump (the air pump is gone could exhaust be going back up in there just a thought)

 

Also check your seals, Hatch, Shift boot, and Door.

 

Especially the hatch. I had the hatch open once when I was hauling my slicks to an autoX and just about got suffocated by exhaust on the way there.

 

my bad guys i have a 88 conv i should of said that

 

It's called owning a modified FC. You'll get used to it.

What year is your car? Also is it N/A or turbo? The reason I ask, is your car may require the airpump to actuate the auxiliary ports (if you have them). If that's the case, you may want to reinstall your airpump and hook the split-air tube back up.

 

any car with a gutted cat will smell funny if you have any window open or air coming in from the street while driving. Test it and you will see I have a str8 pipe with no cats and boy, I well up with only the moonroof cracked open, but if I close it all, and put the a/c, no smell

 

Its an 88 NA Conv i took the air pump off but they welded the splitter tube back on the stright pipe the ports are still on

 

i see

 

How does it sound now that you straight piped it

 

i love it it sound like a lion growling then BAM the roar kicks in I LOVE IT

 

I think it is called the "venturi effect." It basicly swirls exhaust gasses back up toward the front of the vehicle when you are moving. I have the same problem, and it sucks. Also I don't know if there is enough back pressure to open your ports with a straight pipe on there. You might need to do the electric 6pi mod.

 

sounds interesting how is this done the mod i will search but a direct link would be very helpful

 

i dont think it is normal. My 88 n/a had a straight pipe and there was no smell inside the cabin. the only time i could smell the exhaust was idling in traffic with the windows down.

but my 88 TII has the problem you are describing.. the exhaust smell comes into the cabin all the time. the only time you dont smell it is when all the windows are rolled up and sunroof closed. But as soon as you crack a window or pop the sunroof open, the whole cabin is smells like exhaust. all your clothes smell like it after a ride. this would never happen in my n/a

Ive tried changing out the engine/manifold, manifold/turbo, and turbo/downpipe gaskets with no change. bugs the hell out of me

 

I had the same problem...with my NA, but not any more. I had the gasket changed.
The only thing I can say, check the gasket leak ( between headders/down pipe and piping ) - or get a lot of air freshners handy ....

 

Like someone above mentioned, check the rubber shift boots and look for an exhaust leak if it's not exhaust fumes backflowing through an open window when stopping etc.

 

yea, mine smell horrible. smells kinda like rotten egg and exhaust fumes. new downpipe, new bonez hi-flow cat and new apexi dual catback. this was all installed together. but before i installed those, my old stock exhaust had the same smell. i dont seem to find why its smelling so horrible.