back firing.
Using chevron premium gas. In the US.
If you don't have an EZL your car would not be running.
Look left side ( drivers side ) inner fender area top wheel well behind the ABS unit and below the coil
it sounds like its the cats. only on low rpms sometimes starting.
theres no knob
looks like this http://cgi.ebay.com/ebaymotors/EZL-M...-/230298210548
there is a part above it with a knob like thing that screws off to protect it but there is 7ish pin slots but no way to adjust.
Last edited by M103; Aug 31, 2011 at 11:44 PM.
Foolish to try to make adjustments if you don't understand the ignition and fuel control on the M103.
The EZL in the USA cars is not adjustable.
Euro cars have a multi position adjustment that changes timing to account for lower octane gasoline.
Your backfiring problem is probably not due to timing.
You haven't indicated whether it's an intake or exhaust backfire.
Makes a difference.
Have you performed the basics such as plugs, wires, distributor cap and rotor ?
Also checked for vacuum leaks.?
Again all this information has been covered ad nauseum on this and other forums.
Search and you will find an answer and if not then post for assistance.
Difficult to help one that is not familiar with where the components reside in the engine bay
has new step down colder plugs (runs muuuuch better), new bosch wires, Distributor cap looks fairly new(used car), not sure about rotor.
If i cant change timing must be some tubes i really dont want to change cap and rotor. doesnt look easy like an old american car :/
lol looked up price like 60$ im still in mercedes shock lol.
Last edited by M103; Sep 1, 2011 at 02:47 PM.
Colder plugs typically aren't the best on older engines .
Depending on condition a hotter plug is more common.
You should always use the specified plug or it's equivalent.
Resistor plugs no good and newer platinum style with small diameter electrode can also be problematic.
Backfiring in the cats may be the plugs or something in the high tension circuit.
Doubtful it's the timing as the timing typically doesn't move.
You may not be getting a clean burn and some fuel may be igniting downstream of the exhaust valve.
When did the back fire start and what did you do/repair/mod prior to having a backfire ?
Last edited by RBYCC; Sep 1, 2011 at 04:21 PM.
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Been doing this for a while it is getting worse. i took a good listen i think its both the intake AND exhaust.
I bought this old girl used for 600, flat engine mounts etc ect. she is running beautifully but back fire in both cats and intake
Last edited by M103; Sep 1, 2011 at 07:10 PM.
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