SaabCentral Forums banner

Burning fuel fast...bad smell

865 views 5 replies 5 participants last post by  WaSaabiPSI 
#1 ·
So, the title really explains it. Recently I had a new clutch put in my 1995 Saab 900S. She sat for almost 2 months (starting her about once a week).

I am averaging 10 mpg around town, and a thick smell of fuel has been following, engulfing, and irritating me all around town. Today, after a fresh 2-3 inches of snow in DC, I bent down to look at my exhaust tip and noticed it was oddly black as compared to its usual chrome shine. I swiped my finger across the inside and it came back to me looking as though I had dipped it in a puddle of black ink.

Since I bought her one year ago I have replaced:
Linkage, Upper and Lower AC hoses, numerous Heater Hoses, Idle pulley, alternator, Shifter rod, Clutch, and now know I am off to another repair....

Any suggestions?
 
#2 · (Edited)
Another FPR and oxygen sensor ?

Or a set of plugs ?
Or both ?

None of the previous items have anything to do with this, directly.
Bring the engine service up to date and check out the fuel pressure regulator and the O2 sensor.
10 mpg?
Any CELs ?
 
#3 ·
A thick smell of fuel, that is a bit odd, more than running just rich!

There is a vacuum hose which runs from the throttle body to the fuel pressure regulator. That is what makes the FPR "follow" the intake manifold pressure. Basically the 3-bar fuel pressure is modified by the manifold vacuum. As vacuum builds, the pressure drops, so it stays a constant 3 bar above the manifold vacuum.

Bottom line, if the hose breaks, there is too much fuel pressure, and too much fuel, when the intake is on vacuum. The ECU compensates up to a point, but the engine runs rich.
 
#4 ·
All the above.

Change or/Clean regap Plugs, inspect the cap, rotor for cracks. Inspect spark plug wires. Renew any worn compenents.

Remove the air plenum and clean the Throttle Body with throttle body cleaner, and then remove the IAC valve and clean it as shown here (it doesnt matter that it shows the turbo motor, the cleaning is basically the same).

I'd then get under the car and remove the front O2 sensor (in front of cat), inspect and clean with 02 safe carb cleaner and/or a blowtorch to clean off any carbon. Reinstall. If it's beyond cleaning, replace it with a Bosch generic ($50 on ebay).

Check all your hoses for vacuum leaks or cracks, replace/renew with 4mm silicone hoses.

I'd even run 1/2 a can of seafoam or Chemtool B-12 in the next fuel up to clean the fuel injectors too.

-zen

SaabRivera said:
So, the title really explains it. Recently I had a new clutch put in my 1995 Saab 900S. She sat for almost 2 months (starting her about once a week).

I am averaging 10 mpg around town, and a thick smell of fuel has been following, engulfing, and irritating me all around town. Today, after a fresh 2-3 inches of snow in DC, I bent down to look at my exhaust tip and noticed it was oddly black as compared to its usual chrome shine. I swiped my finger across the inside and it came back to me looking as though I had dipped it in a puddle of black ink.

Since I bought her one year ago I have replaced:
Linkage, Upper and Lower AC hoses, numerous Heater Hoses, Idle pulley, alternator, Shifter rod, Clutch, and now know I am off to another repair....

Any suggestions?
 
#5 · (Edited)
Just an additional thought, maybe the local wrench cracked or tweaked a fuel line while installing your clutch and this is causing a loss of fuel pressure between the tank and the injectors? Or maybe a leak has developed by the fuel filter on the gas tank or it's connections.

At the very least he may have cracked the vaccuum line that was just mentioned by PMI above.


-zen
 
#6 ·
zenbeer said:
Just an additional thought, maybe the local wrench cracked or tweaked a fuel line while installing your clutch and this is causing a loss of fuel pressure between the tank and the injectors? Or maybe a leak has developed by the fuel filter on the gas tank or it's connections.

At the very least he may have cracked the vaccuum line that was just mentioned by PMI above.


-zen
Off subject, but Whats up with your avatar? You like that CEL?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top