I will try to get around to it tomorrow after my daughter comes for a visit with my grandkids. The reason I think that the EZL might be a problem is the change in starting pattern. I will see if I can check the timing tomorrow and get back. Thanks for the advice.
Idle Problem That Fixed Itself.........almost.
Today on my way into town I stopped at a stoplight which was red and the engine ideal wandered up rom about 500 to 750 RPM and seemed to have an ignition miss or something. I was a bit worried that it would stall but it didn't and once I accelerated the engine ran fine. This happened about 5 times when I had to wait for red lights. The temperature gauge read 90C and the ambient was about 22C. When I got to my destination I left the car for about 1 hour and when I returned the car sputtered but did start and settled into a nice 600RPM idle and from then on all of the way home it ran just fine? I have no idea what happened. Does anyone have any suggestions ? I would like to know of maybe the ICV might have been sticking or something else to look at.
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My engineer father had a similar resume to your husband. In addition, he was manager of aviation technical service world wide for Mobil so he knew as part of his job how all of the aviation and automotive fuels were formulated. Automotive fuels are formulated with cleaning detergents already in them making additives unnecessary. The MB engineers also recommend against them as well. At this point the additive is in your car so it'll burn out with the current tank of gas. At this point it's looking like the problem isn't a fuel issue so I agree with the other advise that's been given.Well the stuff is in the tank now. My late husband was an air engineer as well as an airforce and commercial pilot and used gas additives in his aircraft and vehicles approved but not recommended by Transport Canada as I recall but honestly can't say which. We used Seafoam in our outboard engines for many years also. It might not have done any good but didn't seem to do any harm.
In any event it is a wait and see at this point since I am not going to syphon the gas from the tank. Thanks for your advice.
I am going to check the CSV and the Temp switch to see if I am getting a shot of gas at the cold start as it seems to be a lean mixture. This happened only after I switched the EZL module. Before the incident when the car wouldnt start the engine always fired up on the instantly.?
W201fan, I am not certain it isn't fuel related but I do want to test the electrical components before I tackle any fuel issues. With the cooler temps I notice that the guage is sitting at about 90C and the car ran like a top today and started nicely when warm.
The cold start took about three short tries but once running settles into a nice idle.
I am pretty frugal so I don't like wasting money to buy parts I don't need in order to find a problem.
The cold start took about three short tries but once running settles into a nice idle.
I am pretty frugal so I don't like wasting money to buy parts I don't need in order to find a problem.
I checked the timing at idle today and it seems to just at the 10 degree mark at 650 rpm. I put a brick on the gas pedal to bring up the rpm to about 2500 but cant read the mark with my cheap po light but it does move.
Hmm, it should move but should be visible, not sure why it is off scale like that. But at least the idle timing is just fine.
BTW, you do not need a brick on the pedal for next time, the throttle actuator is accessible to your free hand though it is a bit hidden under the air filter housing.
So at the moment you only have cold start difficulty?
That is purely a CSV not firing issue. As with a working one these cars start on a dime no matter what is happening with the fuel system in general.
That you will need to diagnose first electrically by disconnecting it and cranking and observing if a voltage is present for 1-2 seconds.
If you pass that test, it may be the CSV itself by taking it out of the car (reconnecting the electrical ofcourse) and repeating the crank test to see if it sprays fuel in a nylon bag.
Hope I'm not stating the obvious here....
- Cheers!
BTW, you do not need a brick on the pedal for next time, the throttle actuator is accessible to your free hand though it is a bit hidden under the air filter housing.
So at the moment you only have cold start difficulty?
That is purely a CSV not firing issue. As with a working one these cars start on a dime no matter what is happening with the fuel system in general.
That you will need to diagnose first electrically by disconnecting it and cranking and observing if a voltage is present for 1-2 seconds.
If you pass that test, it may be the CSV itself by taking it out of the car (reconnecting the electrical ofcourse) and repeating the crank test to see if it sprays fuel in a nylon bag.
Hope I'm not stating the obvious here....
- Cheers!
The timing is not off the scale but rather has moved but I can't determine the exact amount of advance. I don't have arms long enough to reach the throttle linkage and observe the light. I may have to jack the car up an remove the splash guard and mark the timing marks with paint but I honestly feel that the car runs too well once started to be a timing issue. If you examine my previous posts you will read that I wanted to test the CSV as it does seem like it may be a problem but one of the 5mm Allen screws wont budge and the last thing I want to do is strip the that fitting. I have it soaking in PB Blaster and will try again in few days. The thermo switch seems to be within spec also. The car ran flawlessly today on a trip to town save for that start issue. It fires then quits until I depress the gas pedal about 1/4 of the way. Hot starts seem fine.
In that case you are fine. For future reference you can take the airfilter housing off and stand on the driver side fender to do this.
Also for others benefit the timing spec is:
9 degree BTDC at idle
33 degree BTDC at 2500rpm
It maxes out at 35 degrees.
I just measured my original and a spare EZL and got the same results on both.
It is interesting that the timing is not a continuous transition, it seems to go up a couple of degrees every few hunded rpm more like a second hand.
I had suggested checking the presence of a signal without taking the CSV off, now that you are having trouble taking is off. Had you done that before?
Also for others benefit the timing spec is:
9 degree BTDC at idle
33 degree BTDC at 2500rpm
It maxes out at 35 degrees.
I just measured my original and a spare EZL and got the same results on both.
It is interesting that the timing is not a continuous transition, it seems to go up a couple of degrees every few hunded rpm more like a second hand.
I had suggested checking the presence of a signal without taking the CSV off, now that you are having trouble taking is off. Had you done that before?
No I don't think I will try "standing on the driver side fender"! If I can get someone to help I will check to see if the CVS gets a signal although the Thermo switch seem OK at that end of the CVS harness.
LOL, I did not mean "On" the fender Laura, just be on that fender side, instead of in front of the car. I just stood next to the fender and I do not have a long reach, you can do it. I am only 5'9".
Well that is 6" longer than me. I doubt that I fould reach that far. I really would like to check the timing again. I am going to try to move that one stubborn 5mm allen screw in a few days to get at the CSV and test it.
Since you've replaced your fuel filter, use premium gas and do alot of highway driving, I'm now less inclined to think it's a fuel issue. Fuel issues are typically more across the board and consistent. I would suggest checking all of your wiring to see if there might be any corrosion on any of the connections or if any of the connections are loose. They can both or individually sometimes cause a more intermittent issue as you're now describing.
w201fan, I am inclined to agree. I did get that stubborn Allen screw off and removed the CSV for testing. It squirts a small amount of gas when the ignition is turned to start. not sure if that is enough but it does click and open the jet when 12 volts is applied. I dropped a screw down into the oil pan area by accident and had to remove the splash shield to get it back and noticed that the timing marks on the vibration damper were right were I could see the TDC and 10 degree marks so I put a dab of white paint on both. I then rechecked the timing and with the engine in drive and the vacuum hose removed from the EZL at idle the strobe indicated more than 10degrees? Possibly about 15 degrees + or - . Is the too high? I have been reading about this and now wonder if my husband removed the R-16 resistor or if Canadian spec cars didn't come with one? One more thing to look for.
On start the engine fires immediately and then suddenly stops for the first try and then might start and run on the 2nd or 3rd try. It starts better warm than it has it quite a while though so I am quite pleased. I sure am stiff though after being under the car this afternoon. Maybe time for a trip away to do some fishing for a few days with the kids.
On start the engine fires immediately and then suddenly stops for the first try and then might start and run on the 2nd or 3rd try. It starts better warm than it has it quite a while though so I am quite pleased. I sure am stiff though after being under the car this afternoon. Maybe time for a trip away to do some fishing for a few days with the kids.
Whether or not there's a difference between the U.S. and Canadian cars, I don't know. Maybe the MB Classic Center in California could answer that question. This kind of an issue is so frustrating to diagnose as there are so many things it could be. I think a few days away is a good idea.
I believe your CSV is fine, they only spray fuel for 1 second or so just to get that initial start when cold.w201fan, I am inclined to agree. I did get that stubborn Allen screw off and removed the CSV for testing. It squirts a small amount of gas when the ignition is turned to start. not sure if that is enough but it does click and open the jet when 12 volts is applied. I dropped a screw down into the oil pan area by accident and had to remove the splash shield to get it back and noticed that the timing marks on the vibration damper were right were I could see the TDC and 10 degree marks so I put a dab of white paint on both. I then rechecked the timing and with the engine in drive and the vacuum hose removed from the EZL at idle the strobe indicated more than 10degrees? Possibly about 15 degrees + or - . Is the too high? I have been reading about this and now wonder if my husband removed the R-16 resistor or if Canadian spec cars didn't come with one? One more thing to look for.
On start the engine fires immediately and then suddenly stops for the first try and then might start and run on the 2nd or 3rd try. It starts better warm than it has it quite a while though so I am quite pleased. I sure am stiff though after being under the car this afternoon. Maybe time for a trip away to do some fishing for a few days with the kids.
If the car dies after that initial start, it generally is because your fuel system pressure is not building up in time. There could be many culprits for that but I believe you will need a fuel pressure gauge to diagnose that nuisance.
I can check how much the vacuum advance is for you if you like by doing the same.
Thanks, I will ty to source a gauge myself or see if the one garage in town has one although I doubt it. I do know that even after several days there is pressure in the lines when I loosen a fitting. Would that indicate the fuel accumulator is OK ?
I believe there is always pressure in the lines, just not much after many hours/days. So it would be difficult to gauge that without a fuel pressure gauge. You will need a metric adapter for the gauge which is generally harder to source that the pressure gauge itself.
When you acquire the gauge also purchase a set of fuse line pinchers, available at your auto stores. They are gentle on the rubber lines (as opposed to a clamp vice) and very cheap. You can pinch the accumulator line and see if the pressure maintains when pinched.
Your late husband probably had these in the garage though, you may not need to buy them.
When you acquire the gauge also purchase a set of fuse line pinchers, available at your auto stores. They are gentle on the rubber lines (as opposed to a clamp vice) and very cheap. You can pinch the accumulator line and see if the pressure maintains when pinched.
Your late husband probably had these in the garage though, you may not need to buy them.
Thank you, will look to see what a fuse line pincher is and then have a look among the tools in the garage. I think there maybe might even be a pressure gauge although not likley for a high pressure system since his aircraft always had carburetors. Is there a recommended guage on Amazon etc, since it will probably have to be ordered online.
Most of the reviews I read on fuel pressure gauges are negative. I need to take my never used, 40 year old pressure gauge out and give it a try one of these days.
As I also have a small leakage in the system.
You need a gauge with a scale of minimum 100 psi.
As I also have a small leakage in the system.
You need a gauge with a scale of minimum 100 psi.
What might be the negative views? I am considering getting one. No issues with the car at the moment but might want to check things out out of curiosity.Most of the reviews I read on fuel pressure gauges are negative. I need to take my never used, 40 year old pressure gauge out and give it a try one of these days.
As I also have a small leakage in the system.
You need a gauge with a scale of minimum 100 psi.
General complaints are the gauges are leaking right out of the box, product does not have the necessary couplings, etc.
I have not read very many positive reviews but then again, consumers usually only complain and do not write positive feedback.
For these fuel injection systems, it is recommended that a hook-up with dual input (one for system pressure the other for lower chamber pressure), a valve and a single output be purchased/put together. You want to be able to measure the difference between these two pressures and using 2 gauges is probably not a good option due to the inaccuracy in the meters.
I have not read very many positive reviews but then again, consumers usually only complain and do not write positive feedback.
For these fuel injection systems, it is recommended that a hook-up with dual input (one for system pressure the other for lower chamber pressure), a valve and a single output be purchased/put together. You want to be able to measure the difference between these two pressures and using 2 gauges is probably not a good option due to the inaccuracy in the meters.
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