Scott, You say that you get a loss of power at 4000 RPM and above. You did not mention any loss of power on acceleration (while still below 4000 RPM). If this were a fuel related problem then you would experience symptoms during peak fuel usage which naturally would happen during rapid acceleration especially while still well under 4000 RPM). Since your problem is related to RPM instead of fuel demands, I say it is an ignition problem. I would suggest trying a new ignition coil, but you did that already. My next suggestion is to try a different ignition ECU (located in the compartment behind the driver's seat). These modules are a bit expensive to buy as a diagnostic tool, but maybe you could swap one out with a local owner to see if the symptoms move to the other car. If that doesn't fix it then as a last resort start swapping parts with a known good car until the problem moves to the other car. As for what you have measured with your new fuel pressure gauge: DO NOT TRUST IT UNTIL YOU HAVE CALIBRATED IT AGAINST AN ACCURATE REFERENCE. I calibrated mine (and it needed it) using compressed air and compared to a known accurate digital tire pressure gauge. Sounds cheap, but is accurate to within 0.5 PSI. The primary pressure is the pressure produced from the output of the fuel pump. Your measurement of 4.9 is low. But in comparison your rest pressure of 2.9 bar is also low. Both these measurements are within allowable limits; however, your chances are good that your fuel pressure gauge is inaccurate. Here's why: A truly low Primary pressure (if not too low) will not cause a low Control pressure or a low rest pressure. Assuming that your gauge is reading 0.2 bar too low & add this to all of your measurements and it puts them all within normal tolerances. Another thing to consider is that your rest pressure only dropped by 0.4 bar in 10 minutes (2.9 bar - 2.5 bar = 0.4 bar) The manual allows a drop of 1.6 bar. (3.3 bar - 1.7 bar = 1.6 bar) Your system is holding pressure well. > I can set the primary pressure to the setting range of 5.1 to 5.3 bar. How? I have never seen this in any of the manuals. > Will raising the primary pressure affect the Control Pressure? As long as the Primary pressure is within normal limits, it should not. > Is there a way to adjust the Control Pressure? Not that I am aware of. The Control pressure regulator can be rebuilt, but it is not meant to be reassembled without replacing the seals; although, some people have been able to clean them & put them back together without leaks. I have never heard of rebuild kits being made available to the general public. Old cores are exchanged for rebuild. I understand that there is a pressure adjustment on the fuel distributors, but I think this is done by adding/removing shims and it is something that is only to be adjusted during a rebuild. Once set, it shouldn't change. And if it does, that's because it has other problems that tweaking won't fix. Let us know how you progress with this problem. I'm really curious. Walt To unsubscribe from this group, send an email to: DMCForum-unsubscribe@xxxxxxxxxxxxxxx Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
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