1998 Mazda 626 Mazda 626 RPM misbehaves + smell

By looking at the recall, I don't believe it it applicable to my car, since it has been manufactured in july 1997 (though it is model year 1998) and European version. There were a tag on the PCM that is has been reprogrammed in December 1999. The mazda dealer (importer company) said that the PCM (Ford EEC-V) can not be reprogrammed, but they had the information also on their computer (didn't tell why reprogramming was done). They couldn't explain that.

A year ago, before the car started to burn oil with the old engine, everything worked fine. I could live with the alternator noise, but the other faults not. For example the smell coming inside the car sometimes gives me headache and the fact that it's impossible to change gears smoothly makes driving in the city hellish.

I also yet haven't found a common factor for the reasons when the car works OK. (Driving without electrical load and fast acceleration). After a fast acceleration car can work fine for several days. Couldn't be anything but something clogged?

Okay.

I have monitored the voltage while driving with a cigarette lighter battery analyzer, and an voltmeter connected to it. The voltage while driving has been around 14, 4-14, 65V, never seen it drop, even when the RPM goes low. Only slightly for a moment when electrical load is turned on. Only thing which I noticed is that sometimes when I turn ON the headlights or other load, the voltage goes UP about 0, 1 or 0, 2 volts.

The strange thing about the electrical load applied to the car is that I have a 350watt audio system (amp and subwoofer) in the car but that doesn't change the behavior of the car at all like the other things do, no matter how loud I listen music (takes more power than headlights, right?). It has a separate wiring straight from the battery to the amp. The system has been disconnected for months now (the system is physically removed, only the power cable and RCA cable are still in the car but disconnected from both ways and taped with electrical tape), the last three alternators haven't been run with the stereo system connected so the system couldn't be the cause.

That kind of let's me think about the fuse block in the engine bay, but every fuse is OK.

About the fast acceleration thing when it happens: First when I take off (pedal to the metal), the car almost doesn't move, lacks power (maybe misfires?), But then goes off like a rocket after about 50 meters. This has happened three times, everytime before this there was a bad smell coming inside the car, that smell that I haven't had since the clutch replacement.

I experienced some things today, that are new.

I got another smell. I don't know which the rotten eggs smell, but it was similar to "fresh" asphalt when road workers repair roads added with fuel. It occurred when I was accelerating very fast, and it took a short while before it stopped.

I also had bad fuel economy day today, the car consumed about 50% more gasoline than usual. I was driving 100km/h on freeway most of the time.

I also noted that there is a hose in the engine bay that goes nowhere and is plugged with a cap. I found out that it's the engine oil cooler water hose.

The parts catalogue tells my car should have the oil cooler, but it is not there. In the parts left from the engine change, there is the another end of the oil cooler hose. The oil cooler seem to have disappeared during the engine change. Can this or the way that hose is plugged affect something?

My car doesn't have the MIL.

The oil level is OK. The new engine is driven only 45000miles, so I can't believe there's something wrong with the engine itself.

The European version of the car, which I have, doesn't have the Check Engine light at all. AFAIK European 626 has the light from model year 2000 (facelift with the new meter hood), and mine is 1998.

I also checked the OBD codes, but there was none present this time.

I found a cheap used PCM on ebay with the original immobilizer unit, and I think I'll give it a try. The Mazda mechanic said it fits the car since the immobilizer is within.

I just remembered one thing: When the engine was changed, mechanic had put too much oil in it (Almost two times too much). It was noticed about two months later, and the extra oil was drained off the engine. Can this have damaged my engine or the exhaust system?

I ordered the new PCM, should arrive in about a week.
I noticed that the vibration at idle occurs again, it was gone for a few weeks but now the car shakes like a tractor when stopped at idle.

Yes. The strength of the vibration varies when electrical load is turned on or off. When the car has worked fine, the vibration has been gone too. It comes somewhere from the passenger side and is stronger in the interior.

Just a thought when waiting for a new PCM:

Just a little time before the engine change, the car had a little accident. Three of the five wheel bolts of the passenger side front wheel came loose (mechanic's failure, forgot to tighten them) resulting the alloy wheel to bend. It had to be replaced.

I just thought, that maybe the ABS/Speed sensor on the wheel could be damaged from that? Can it cause any of my problems? Is this a totally ridiculous thought, or should I look into it?

Just thought of it because the RPM makes a little notch when the car stops, and also the car sometimes works fine for a moment after it has been on the mechanic (probably off the ground?).