mpesik

Hi . Is this the result of the cat gutting or is there something else wrong here!! I did -NOT reek like this after the operation. Anyone? Thankyou. Car is still burning on the rich side. Mike

goodspeed928

You now need to reset the gas/air.
You are getting to much air.

hupp

My '79 has been exibiting the same symptoms -- also have a gutted cat.

mpesik

Hi godspeed. Unfortunately I can't ,I have an 88. ME

Bill 86.5 928s

Mike....Is your O2 sensor still intact?......maybe the connections????....Bill

JKelly

Do you mean strong fuel/exhaust smell, or some other kind of smell? When I by-passed my cats, I took a spin around the block while my air pump was still blowing air out of the feed line that went to the cats. When I parked in the garage I noticed that the air coming out of the feed line smelled gross...I put my face in it.....it wasn't a fuel smell, it was more like a smog smell. Could that be it?

mpesik

Hi Bill 84s-O2 sensor is connected. After gutting I noticed it was NOT connected-probably since I've owned it-8 Years!!!- Gas Mileage is down a bit too!

Hi JKelly-Air pump is pumping- It is a true diesel smell!

Thanks for replies,guys. Mike

ViribusUnits

Did you let the car warm up?

When the engine is cold, the fuel system dumps extra fuel in to maintain driveability. Engine cold = smells like a 70s car. What your smelling are the aromatics, which are the exact same compounds that don't burn so well in desiel engines.

Also, w/o a cat, the car is going to exaust gasoline. The exauste is not hot enough to burn the gasoline with the air being pumped into where the cat was. You'll find on non cat cars, the smog pump pumps air into the exauste as close as possible to the engine heads. This way the exauste is as hot as possible, and most likely to burn up.

Also, IIRC, with the idle loop engaged the computer innores the O2 sensor and enrichs the mixture just a touch to keep the idle smoother. I'm ot 100% sure on this.

Garth S

My '88 arrived without an air pump - and now has a gutted 'test' cat: there is no pronounced or unusual exhaust odour. Fuel economy is steady at ~10l/100Km.
As mentioned previously, the last thing touched that could impact fuel economy ( and odour) was the O2 sensor: No signal back to the LH module is better than an erroneous one - disconnect the sensor for a trial (inside the fuse panel). Also, test its voltage outpot when hot.
Here's guessing a new 3-wire sensor is needed ( I keep a generic spare).

hupp

Viribus,

I was under the impression that the smog pump normally discharged into the air box. At what point (during operation) does the pump discharge into the exhaust ports behind the cam towers?

Bill 86.5 928s

Mike...I was out your way last week and I stopped at a Petro Canada station between Calgary and Medicine Hat. While I was pumping fuel into the van I thought the odour of the fuel seemed strange. You nailed the smell right on when you said diesel. It smelled like a gas diesel mix and it probably was as the power just seemed to be lacking. I have also noticed the same thing here in Ontario so it wouldn't surprise me that some hocus pocus is going on here in Canada. Good-luck with the problem and I hope you find an answer. I'm curious......Bill

heinrich

Bill excellent point. Some gas even has blue, red, orange coulur it deposits too. But bottom line MPesik, your O2 sens was inop, maybe make sure the whole system is now working before trying to chase this smell down ...