try a new distributor

 

Been busy and haven't had too much time to work on the car. Been thinking about the timing belt after Kennin's first post. I took the Timing Belt (TB) covers off and the crank position was somewhere around compression stroke on Cyl 6.

To my amazement, I could easily slide the TB back and forth on the No. 1 idler pulley. I rotated the engine to Cyl 1 and the belt became taught. Checked the alignment marks. The front cam was off by 1/4 tooth and the back cam was off by 1/2 tooth. The TB is original Mazda part and I don't know how long its been in there or whether it has ever been changed. I do know that the TB covers had been pulled off before. The car has 167K miles.

Hopefully, I have found the problem. I will also check tensioner while I am at it.

 

I've replaced the TB and the car performs well when the engine is cold...an improvement. As soon as it warms up, it goes back to its old way of accelerating slowly although much improved. The afterfire is gone except for an occasional one. Car works fine over 2500 RPM. Fuel trims have improved for both idle and driving conditions.

 

Success!!! I swapped out the distributor and all is normal...Millenia lives again. Of course, I don't want to dish out $300+ for a reman disty or a new one for that matter. The next step is to figure out which part in the distributor has gone bad. First on the list is the igniter since there seems to be an ignition timing issue as evidenced by the afterfire or backfire.

 

I did a GM equivalent ignitor mod while trying to keep the car as much stock looking as possible. This improved things but not 100%. Still had issue and small afterfire between 2000 to 2500 RPM. Replaced the coil with a stock one and that cleared that up. Now the car runs great. Spent a total of about $100 for both ignitor mod and coil, essentially the distributor is new now.

Anyone who says ignitors are either good or bad is wrong. There is a middle zone for this item where it will not perform perfectly but the car would run. The resistance test on the old coil passed but the coil was still bad as it caused issues in the 2000 to 2500 RPM range. The resistance test would be a acceptable indicator if the ignition coil was completely dead.

Ignitor, ignition coil, and timing belt were the three items that were replaced to get the car back on the road. The timing belt probably had the least bearing between the three items. Total cost in parts ~$140, labor...don't ask, knowledge...invaluable.

Hope this help all those with an issue like mine; although, I wish I had a lot more input from those who viewed my posts.

 

I have learned 2.5 L engines have a problem with the ignitor going bad whether it is in Millenia/MX3/MX6/626/Probe, however, I did not run across a single post about this as related to Millenia. Unless if you replace the entire distributor, you cannot just replace with a stock ignitor...you will need to do a mod.

 

No power at all unless I use a feather to touch teh pedal.. runs fine when cold but starts in after about 60 seconds. Idles ok. I can put in manual mode (HOLD) and control the rpms and move the car up the road but in drive you can almost forget it.

What year is your Milly? I saw several posts after seeing your thread here that discussed various Mazdas (like you said, no one has a millenia with the problem that posted about). However everyone says a '94, '95, etc. My Milly is a '01 2.5L and not sure if the HEI mod will work on this model.

Any info you can share would be greatly appreciated. Most fo the linds I found are dead on the mod and the ones that did work weren't detailed (links in those threads were to detailed sites but they didn't work). Any specifics you care to share would be great.

Hoping yyour even still around to share the info..

Eric