Engine Mechanical problem
1998 Mazda 626 4 cyl Front Wheel Drive Manual 140000 miles
I asked for help some months ago, but my car still doesn't work any better.
The prologue: http://www.2carpros.com/forum/1998-mazda-626-engine-dies-when-pressing-clutch-vt232363.html
The main problem is still the misbehaving RPM when I press clutch or let the gear to neutral. All the other problems are still there.
I have noticed something during these last months though:
- When using clutch, f.e. clutch pedal pressed when at traffic lights, sometimes a horrible smell comes from the engine bay. If I let off the clutch, it stops. It's worst when for example trying to get over some obstacle or when trying to get off the snow. The smell isn't any fluid.
- Sometimes when accelerating very fast, something (metal?) kind of "bangs" on the engine bay, and the car could WORK FINE for several days.
- The neutral gear switch gives weird readings, the whole engine electrical system was checked and everything else was OK.
- The alternator voltage has been measured while driving for several hundred miles, it's 14,5V steady. When idling, it drops to 13 slowly. Alternator was also checked with oscilloscope and it was OK, so I don't think it's the problem.
- The engine temperature meter is just below the center point, not right at the center.
- Throttle body, TB gaskets, TPS sensor, IAC valve and EGR were replaced.
- Sometimes the car doesn't find the idle RPM, the needle in the RPM meter just moves from 0 to 1000 and the car sounds like it's dying. BUT when I give it throttle almost to the redline, it finds the idle.
I don't think the problem is related to engine electrical, since the whole system was checked, the only malfunction was the neutral switch, but it was replaced and still doesn't give right readings.
What should I check next? Clutch? Fuel system? Cooling system? Exhaust?
What can cause that smell? It's not the famous rotten egg smell, but as horrible as it is.
There are no diagnostic codes present anymore.
Thanks in advance.
have the same problem?
Monday, April 13th, 2009 AT 9:59 AM