stinky 308

I have a 1980 308gtsi, it runs great but the fumes it puts out makes inpossible to drive the car with the top off. You can't stand behind the car with the engine running. I took the car to a shop and had it put on an exaust analyzer and the hydrocarbon's were 2000 parts per million. They told me that it probably needed an ignition tune up, spark plugs wires etc. I don't dispute this, except that if it had ignition problems it wouldn't run very well and it does. One other thing. When we had it on the machine I unpluged the front bank coil and the hydrocarbon reading fell to about 90 parts per million. When I pluged the coil back in the reading stayed the same and the fumes seemed to dissapear. Can someone explain to me what happens when the throttle is at idle. It seems that at idle the front cyls are not getting fuel. If you unplug the front coil at idle the car runs normally. If you unplug the rear cyl coil the engine dies. Is this the way it is supose to work. The car runs better for a while after I unplug the front coil, then reconnect the coil. Are the probes in the cats just thermocouples that turn on the slow down lights , or are they oxy sensors that talk to the fuel injection computer. Thanks for any input .

 

I also have a 1980 GTSI and also the same exhaust smell. My clothes always smell of a strong exhaust smell when I am finished driving her.
What color is yours? Mine is red/black with 53,000 miles, made in Sept 1980.

Frank

 

Sounds like Air/fuel mixture problem. Does not explain why turning on and off 4 cyl's would effect it though.

 

I can't say for sure, but some people have complained that 348's can smell if the catalytic converters have been removed. Does your car still have original cats? If not, adding them may solve the problem. Again, I can't be sure.

 

A 308 will 'single bank' just fine, upon ignition failure, but you'd think you'd see it on the 4 gas analyzer....those guys sound like they are throwing parts at it, do you have any faith in them on Fcars?

A 1980 example should indeed be running catalytic exhaust, hopefully functioning! You might have it there.....you'll have to get some injection gurus in here (I'm a carbed example), but even at idle I think all 8 cylinders meter the same, on a good day.......

 

do carb'd cars smell worse than injected? I have the same problem with the fumey exhaust. and what are we smelling-burnt or unburnt fuel?

 

No, JRV could tune my carbs down to pass all 4 gases..he was good...I don't recall if that was the best performance though.

And now we don"t test cars as old as my 1976, 1977s...

But my point being BAD numbers means something is wrong, but the mechanic should know, not just say "you need $500 in wires"....they can see the spark on the scope!! Actually there's a gap test gauge tool for checking ignition output at the spark plug....but you get my drift......

 

Most interesting post. When you state "it runs great", I must ask "in comparison to what?"

With HC at 2,000 PPM, you're at over 10 times what it should be. Extremely high HC readings are always due to misfires...Before I'd spend a dime in repairs, I'd want to see compression, leakdown and the rest of the emissions readings.

The Ferrari V8 is essentially two four cylinder engines, sharing a common crank and fuel injection system, although two independent ignition systems. So, to answer your question, she should run reasonably smoothly with one, or the other coil wire pulled. If you unplug a coil and the engine dies, then that bank has some sort of a problem...

These cars will run and drive quite well on just 4-cylinders, although power will be down considerable.

(And the chance that the fuel injection system is "only supplying fuel" to just one bank; extremely unlikely!)

Diagnostics first-Then perform repairs.


David

 

Guys,

I am clueless here. I grew-up with no-cat cars and cars with NO emissions control of any kind. My dad has two Model T's and you can't get much more polluting than that. I never considered them "stinky."


What are you calling a "bad smell" or "stinky." I honestly want to know.


If it is the same cornicopia of aromas (gas, exhaust, oil, rubber) I'd inhale at the drag strip on a hot, muggy summer's day, my cats are coming




O_F_F ! ! ! ! ! !

 

You defenitely have a severe problem here
your car is not running great...it is obviously running on one cyinder bank only
HC as a measurement of combustion should read around 180ppm or less, CO around 1-1,5% (up to 3% if tuned a little rich)

the probes are temperature sensitive and turn on the slow down lights as soon as the cats get too hot....you do not have a FI control unit
if you still have your cats, then running on just one bank probably already destroyed the other bank`s cat because of unburnt fuel igniting within the cat
(if in working order, the corresponding slow down light should stay on permanently in this case)
definitely fire danger here !!

No ...
each bank should be able to run separately...(for testing reasons)
seems your loosing your front bank here (cyl.5-8)
btw watch out unpluggig a coil wire while your engine is running (at least you should keep your passive hand in your pocket...ask me how I know )

make sure you have spark
check plugs, plug extenders, wires, distributor caps, rotors and coilwires

swap coils pysically and see if you can transfer your problem to the rear cyl. bank
if your problem moves over, you might have a broken coil
if it stays with the same bank, you should check the tdc/ pickup sensor on the flywheel (the lower one on the left is the 5-8 pick up)
after that check/swap your 2 ecus (electronic control units), left side of your trunk under the carpet and also check their ground wires !!


if you do not know what all this means, make sure you ask someone who really knows these cars
throwing darts by some mechanics is not the right thing to do
you might also fill out your profile and where you`re located so it will be easier for people near you to lead you in the right direction

read and learn about your car as much as you can...it`s part of the fun of ownership !
this is a great community and a fantastic forum
and a lot of very knowledgeable folks are eagerly waiting to help you...and all of us


best regards from Germany
Michael

 

On spark cables issue one could prob by grabbing after splash with water. If you bounce you know you're in trouble

 

William,

Give this a try and let us know how it works

 

hey everyone thanks for the responses especially michael from
germany. I think you are right I have lost the 5-8 cyl bank and I should have picked up on this ,but the fact that the car ran normally at idle and under power. I drove the car yesterday and when I got back I pulled spark plug wires off one at a time and didn't find a rpm drop , yet there is spark at the wire. I'am going to pull the plugs and do a compression check. I think i'am going to find that the plugs are fouled. I also think i'am looking at a valve job some oil consumption. The thing that threw me off is the fact that the car really does run good. If you pull a plug wire off one of my jags plugs the car runs bad. In this case I can pull 4 wires off and the car continues to run smoothe. I think the difference is, the 308 has two 4 cyl engines back there and you have to look at it like that. I will let you know what I find. THANKS

 

Suggestion;

Use Michael's checklist as your guideline.
Because of the way the "quote" function is, Copy/Paste Michael's checklist onto a new post.
As you progress and eliminate "suspects", remove a no longer relevant sentence from the Copy/Paste.

Through process of elimination, this will help you and the resident experts diagnose the problem.