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Car smells like a two stroke engine (gas)

  • Thread starter Thread starter streetstang67
  • Start date Start date Mar 17, 2008

streetstang67

Member
Mar 5, 2003
573
0
16
Lexington, SC
Mar 17, 2008
#1
  • Mar 17, 2008
  • #1
After driving my car for any length of time, I smell like the exhaust of a two stroke engine...I smell like "burnt" gas. What can I adjust to make this go away. Its a '67 mustang with a 289 and holley 600 cfm vacuum secondary carb.

How can I fix it?

Thanks

------------------------
'67 mustang with 289
Holley 600 cfm vac sec
Performer intake with 1" open spacer
Mild cam
Multi angle port/polish work on factory heads
Hooker long tubes
 
R

runawayabc123

Member
Mar 9, 2007
192
0
16
Wisconsin
Mar 17, 2008
#2
  • Mar 17, 2008
  • #2
I hate that smell too.

But I will have to ask the obvious, any exhaust leaks? Everything burning right? (Not to rich or burning oil?) (Aka, what shape is your engine in?)

Is your firewall in good shape? Cowls? (ie bad air flow into the drivers compartment?)
 

streetstang67

Member
Mar 5, 2003
573
0
16
Lexington, SC
Mar 17, 2008
#3
  • Mar 17, 2008
  • #3
Engine has been recently rebuilt, should be fine, seems to be in great shape. No obvious exhaust leaks.

It could very well be running rich, but I don't know how to fix that... is there an adjustment on the carb, or would I just have to change jets?
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Mar 17, 2008
#4
  • Mar 17, 2008
  • #4
Where does the exhaust exit the vehicle? Behind the bumper?
Also, any rust holes in the sheetmetal?

Idle mixture can be adjusted by turning a screw on the carb, but to adjust the mixture for under load conditions you'll have to change the jets.
 

mrmustangman357

Member
Feb 11, 2007
763
3
18
Mar 17, 2008
#5
  • Mar 17, 2008
  • #5
do your eyes water? check the plugs and see how rich it is running
 

woodsnake

15 Year Member
Jan 16, 2007
1,353
15
69
Hicksville, NY
Mar 18, 2008
#6
  • Mar 18, 2008
  • #6
How old is your Holley? I think models made before 1994 still had a potential for power valve failure.
If yours is newer, then probably nothing to worry about.
 
M

mikethebike

Member
Jun 12, 2007
358
0
17
Greenville, SC
Mar 19, 2008
#7
  • Mar 19, 2008
  • #7
woodsnake said:
How old is your Holley? I think models made before 1994 still had a potential for power valve failure.
If yours is newer, then probably nothing to worry about.
Click to expand...

Power valve failures usually require you to keep your rpm up around 3500 or better to keep the engine from stalling due to far too much gas.
 

mikec35

Member
Jul 6, 2004
233
2
19
NC
Mar 19, 2008
#8
  • Mar 19, 2008
  • #8
Like Bottlefed is thinking.. make sure your exhaust exits the back of the car and does not stop short of the rear valence.. This will make a huge difference in smelling the exhaust, whether it is running rich or not.
 

garner67

New Member
Jun 30, 2006
68
0
0
SF Bay area
Mar 21, 2008
#9
  • Mar 21, 2008
  • #9
mikec35 said:
Like Bottlefed is thinking.. make sure your exhaust exits the back of the car and does not stop short of the rear valence.. This will make a huge difference in smelling the exhaust, whether it is running rich or not.
Click to expand...

I have a similar issue with my new 351w, and this is an interesting note.

Even though my exhaust exits the pipe 2" past the rear valance, I wonder if my poorly fitted deck lid and old weatherstripping seal is letting a lot of fumes into the car?
 
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