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Discussion Starter · #1 ·
When I changed the spark plugs I noticed that the centre electrode is bright white with no trace of a sandy color. I had suspected she is advanced, could poor fuel delivery effect the ignition timing?, or what would be the most probable cuase.
Thanks
Mike
 

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They can't really be advanced as it's electronicly controlled. I would wager you are witnessing a lean condition. How many miles on your car? Ever service the fuel system?

Jonathan
 

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Discussion Starter · #3 ·
145k miles Jonathan, no I havent serviced the fuel system, but I have two new pumps and filter but I dread the fact that when I replace them I will have the same problem.
Will replace them this week end even just as a process of elimination.
I checked the ignition timing with a strobe lite and it was well advanced, just wondering if the fueling system could effect this.
Thanks again
Mike

By the way, anyone know where I can get a good workshop manual for my car. Prefferably E mailed to me as the customs over here will charge about 40% extra for anything posted.
 

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well, then I'd wager your CO could use some adjusting. Do you have the anit tamper ball out yet? Also, these cars do come set up a little on the lean side which you can correct using the EHA. If you take the EHA off, you will see a small screw, take that off and you'll find a Very small hex head. Turn that a fraction, ie a flat or so to the right and re-install.


What kind of mileage do you see w/ this car?

Jonathan
 

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You will not affect timing by changing anything in the fuel system!
Your timing will be advanced, but I do not remember how much.
I agree with Jonathon you are prabably running lean. However to check for proper timing you take off valve covers turn crank to tdc, and check alignment of timming mark on the cam gear to the mark on bearing tower.
A lot of factors are involved here. The condition of the timming chain and guides etc. If everything is good and you need to adjust timming, offset keys are available for the timming gear.
 

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JEFFMG1 - 1/29/2005 8:55 AM
<snip> ...
However to check for proper timing you take off valve covers turn crank to tdc, and check alignment of timming mark on the cam gear to the mark on bearing tower.
A lot of factors are involved here. The condition of the timming chain and guides etc. If everything is good and you need to adjust timming, offset keys are available for the timming gear.
Aren't you confusing ignition timing with valve timing? I think Jonathan was talking about ignition timing (distributor advance).
 

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Have you ever changed your O2 sensor? They do wear out and should be changed. Disconnect it under the passenger floor carpet/panel and see what happens to your plugs. Also, if you do change it, you don't need an MB sensor, go to mbcoupes page and search on O2 sensors,you can use a Ford sensor and slice the wires for a third of the cost.
 

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Discussion Starter · #8 ·
Firstly thanks for all the help guys. I didnt get a chance to change the fuel pumps over the weekend, this week hopefully. Its the ignition that appears to be advanced. What do I actually unplug under the footwell and where is the sensor located on the engine?
Thanks again
Mike
 

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If you getting through fuel pumps, are you sure that it is just not some crap in the fuel lines? It would explain your engine running lean if it's not getting enough fuel!

Our cars are at an age now where rust in the fuel tank is not uncommon.
 

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The chances of your engine being advanced are very slim to none. Baring some major EZL misfunction (the likes of I have never heard of) or someone changing the chain incorrectly you can not advance these motors. With age and chain strech/timing gear wear they will retard up to 8-10 degrees per bank, but that's about it.

Jonathan
 

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Discussion Starter · #11 ·
I agree Jonathan highly unlikely that the engine timing is out. I checked the ignition timing with a strobe at idle and it appears to be firing too early. What do I unplug under the footwell to disable the O2 sensor?
Stumbles on acceleration if given too much of the right foot until she kicks down then pulls away strongly.
Will lack of fuel cause advanced ignition and how come she only stumbles on initial take off and when accelerator pressed too quickly at any speed. If it is starved of fuel at take off how is it able to do 100mph? Totally confusing,as I say she was a perfect starter any time hot or cold, but one morning it took ages to start, thats why I suspect a sensor or somthing similar effecting timing.
Still live in hope that it will return to its perfect starts.
Thanks
Mike
 
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