What have you done to your P5 today?

replaced air cleaner boot, the old one seemed to be turning into plastic. noticed the previous owner has replaced both O2 sensors and forgot to secure the connectors back into place. Noticing coolant temperatures are climbing as high as 226 when I make the return trip home and go up a steep grade. radiator has a few debris on the lower 1/4 of it. going to clean that out tomorrow when I replace the swollen upper rad hose.

curious, what temperatures do y'all see from OBD data when loading the engine down pretty good? Normally I don't notice much fluctuation on mine when pulling that same hill but I do reckon the debris has something to do with it this time 😂
 

pcb

The Diagram Dude
:
2002 MP5
About our pistons and oil rings...

20210627_185134.jpg

Smoke on cold start​

gozz

Bumping the thread back, with some good/bad news...

Well, the good news is: I found the problem of cold start smoke.

Bad news: Well, it's the rings...

Worse news: The rings are fine, not worn out, not scored, not broken...So, what is it then?

Ok, here's the details:

Mazda's pistons are crap! So f#"$%&ng bad, because they have one design flaw. The flaw that mazda jerks did not put any improvement in the pistons dept in 20 years!

The oil ring channel on the piston, has just 4 (four) tiny oil holes. Theese holes are used for the oil that was scraped off the cylinder walls while the piston was moving down to escape to the sump.

Naturally, more holes, bigger holes, the easier it is for the oil to sink down...

Ok, so, during time, oil and gasoline carbon deposits gradually plug these tiny holes up, preventing the oil from flowing down, and cooling the pistons, and bla bla...

The pistons overheat slightly, causing the oil that gets caught in the oil rings retainer to get sticky and guey and carbonised, turning it self into that hard -impossible to clean- resin / gunk / lacquer that sticks to your kitchen fry pans...

So, at the end you are left with the oil rings that are so badly stuck, glued, burned into the oil channel of the piston, that the oil rings do not even touch the cylinder walls.

The compression rings are a whole different story, and they are doing their job pretty good.

To make things worse, oil rings have sooooo weak initial tension, compared to the compression rings, that it is almost natural to have such a result.

Take a look in this picture. Look at the gap between ends of the compression rings, and compare to the gap between oil rings... You will get the idea..


Ok, so why does it only smoke on cold starts...

Well, here's why:

Once you start up the cold engine, there is increased idle rpm, creating a huge vaccum in the intake manifold, as well as in the cylinders, as the pistons are trying to suck the gases in, but the throttle fully closed prevent thet from happening...

So, as the oil ring doesn't seal the oil, the vacuum sucks the oil past the compression rings ** and into the combustion chambers, and.... tadaaa! Bluse smoke. Now, the oil is fresh and cold, hence, there is no pale blue smoke, but thick white smoke, clearly smelling like oil.

As the engine runs, 10, 20, 30 seconds later, the piston warms up, the compression rings warm up, expand a little, close the gap, so does the crappy oil ring, that finally starts to touch the cylinder walls, and the oil stops sipping up onto the piston.

There is stil some run by, but not so noticable, so the oil consumption is pretty high.

The solution:

Rering the sucker, but drill some extra drain holes in the piston oil channel, and make the existing ones a bit bigger.

** Compression rings are designed to hold the pressure, but not to scrape the oil of the flat surface. it is like your rain wipers on the windshield. They have to be thin, almost blade-like, to be able to scrape.

That is the reason why the compression rings do a perfect job of sealing the compression but leak oil past them like swiss cheese. And why oil rings are thin, blade-like!
 
- Finished replacing front bumper after installing new aftermarket headlight assemblies and replacing burned out low beam bulbs and di-electric grease (old fixtures were crap with broken mounting parts and missing bulb mounting clips).

- Flushed and ran new brake fluid through Brake Master Cylinder and all the brake lines.

- Silicone sealed around tail lights where water was getting into back hatch/spare tire well areas (after reading water leak posts).

- Removed/cleaned/replaced O2 sensors in advance of installing rear 02 sensor spacer adapter (to clear recent P0421 Catalytic Converter CEL if it pops up again).
 
Did some spot cleaning on the seats today, found an old audiovox cell phone from about 2004 down below the parking brake. saturday I got the new solenoids in. only chasing one more CEL code, same as the guy above me here P0421. new coolant reservoir and upper rad hose. noted both of the hose attachments on the engine side need replaced, they are corroded badly near the lip and the lower one leaks a little on warm up. fixed the radio wires where prev owner decided to delete the factory connector and just twist the wires and electric tape them. they managed to get the left and right channels crossed, at least they were wired in phase.
 
- Installed the Downstream an O2 sensor "Defouler" adapter to get rid of the
P0421 CEL (Pre-cat) code that recently popped up a couple times after clearing other codes (photo attached).

-- I used PB Blaster to wet the 02 sensor base down overnight and right before removing the sensor and used a 3 piece 02 sensor "free rental kit" (pay for it and get reimbursed when you bring it back) from Advanced Parts Store that worked REALLY well removing it.

- Installed a piece of 2" I.D. Sch40 PVC Pipe X 3" long into air inlet pipe where upper cover enters lower pipe (no gluing-just drop it in).

-- That area doesn't have a good seal (at least not on this P5) so it bridges the air gap so air can flow straight through to the air cleaner and beyond.

-- The pipe sits above the 90* turn opening to the air cleaner so does not interfere with the air flow.

- After finishing installation of front bumper and new aftermarket headlights (that have 2 beam adjusters vs 1), I tried to adjust high and low beams and found out that one of the adjusters on each fixture is buried behind some of the radiator support/fender metal work that can't be accessed from the back (photo below).

-- The company brand (DEPO) made a slotted adjusted wheel provision to turn them with a tiny screwdriver along with a "capped" headed Phillips/Bolt head, and is a PITA to rotate in those tucked away areas.

-- If someone chooses to buy these fixtures, I would recommend cutting a little bit of metal away in the corner where they will mount to where you can have access to get at the adjuster from the rear through the fender-well area.

eBay Links - P5 Headlights - with Seller Pics

-- The do have bigger screws and wire clip holder arm shown in the photo below so that's an improvement over the (IMO) crappy original equipment lightbulb installation design.
I personally like the plug it in and rotate-it-to-lock design.
 

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i12drivemyMP5

___ 323F ___
Contributor
Finally got the retrofits down out of the attic I have had for years and tightened up the projectors to the reflectors. Think I'm gonna luck out and not have to bake them open to stabilize the shaky projectors. Tightened them a good bit and put red loctite on the threads. Also made sure the cutoffs are level.Found new h1 hid bulbs in box with lights. Ordered the spring clips needed to hold them in projector. Have a pr of morimoto 35w ballasts and battery harness from another hid setup on hand. Getting bulbs secure in projectors is only holdup on them going in the car. Have some yellow halogen brights and silverstar parking bulbs out of the current halogen fixtures....can't wait to go back with hid lows in proper housings with correct cutoffs and effective halogen brights as well. Matters since no fogs in msp lip......

CC859B14-452B-4255-B684-0F4740D7873E.jpeg
49863A75-0250-43F8-8E81-2002C4911772.jpeg
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BenjiHoggi

OEM+
:
Oregon, USA
:
22v Protege5
-Installed the Downstream an O2 sensor "Defouler" adapter to get rid of the
P0421 CEL (Pre-cat) code that recently popped up a couple times after clearing other codes (photo attached).

--I used PB Blaster to wet the 02 sensor base down overnight and right before removing the sensor and used a 3 piece 02 sensor "free rental kit" (pay for it and get reimbursed when you bring it back) from Advanced Parts Store that worked REALLY well removing it.

-Installed a piece of 2" I.D. Sch40 PVC Pipe X 3" long into air inlet pipe where upper cover enters lower pipe (no gluing-just drop it in).
--That area doesn't have a good seal (at least not on this P5) so it bridges the air gap so air can flow straight through to the air cleaner and beyond.
--The pipe sits above the 90* turn opening to the air cleaner so does not interfere with the air flow.

-After finishing installation of front bumper and new aftermarket headlights (that have 2 beam adjusters vs 1), I tried to adjust high and low beams and found out that one of the adjusters on each fixture is buried behind some of the radiator support/fender metal work that can't be accessed from the back (photo below).
--The company brand (DEPO) made a slotted adjusted wheel provision to turn them with a tiny screwdriver along with a "capped" headed Phillips/Bolt head, and is a PITA to rotate in those tucked away areas.
--If someone chooses to buy these fixtures, I would recommend cutting a little bit of metal away in the corner where they will mount to where you can have access to get at the adjuster from the rear through the fender-well area.

eBay Links - P5 Headlights - with Seller Pics

--The do have bigger screws and wire clip holder arm shown in the photo below so that's an improvement over the (IMO) crappy original equipment lightbulb installation design.
I personally like the plug it in and rotate-it-to-lock design.
Shoot, I've got a stock pair of P5 headlights that just need a polish. I should have put them up for sale on here earlier heh.

Not sure if you tried this, but I believe that adjuster is meant to be rotated using a Philips screw driver. I figured that out when I installed my retrofitted headlights a month back or so.
 

pcb

The Diagram Dude
:
2002 MP5
^^^ What he said.

You can reach down from the top with a Phillips screwdriver to adjust them.

The plastic "wheel" has notches in it to fit a Phillips screwdriver.


20210803_085829.jpg
 
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pcb

The Diagram Dude
:
2002 MP5
These are the options...


20210803_160003.jpg


20210803_160339.jpg


20210803_160314.jpg




The pictures are from my parts car and I have half the engine removed.
I don't know how much crap would be in the way on my DD.

A regular Philips screwdriver is probably the easiest.
 
Not sure if you tried this, but I believe that adjuster is meant to be rotated using a Philips screw driver. I figured that out when I installed my retrofitted headlights a month back or so.

Huh, that's why I couldn't figure out how to adjust the ones on the spectra I sold before I got the p5, they didn't have the 10mm head, just the Phillips head in the center and the little teeth. I dealt with that car being cross eyed for a WHILE.
 
Got a leaf in the blower fan for the ac, getting the fan out was wayy easy. after looking in there a little bit I decided to start tearing into it more and found the evap core was 1/4 way covered on top and bottom with leaves. spent some time cleaning all that out. kudos to mazda for making a easily serviceable system. next on the list is the blower speed switch, it gets warm to the touch and I have to wiggle it a lot to get the ac to stay enabled. I checked the connector and it's not burned and the terminals look healthy. thanks to prev owner for not securing the radio in so I can easily get back there to look at it.
 
Today, wheel studs and an oil change since there was no record of the last one being done. The passenger side brake was missing the bottom slide pin :eek:... Had to drive 45 minutes away to get ahold of one. The studs were rather easy to get knocked out and not too bad to get them to pull in with just a lug nut and the brake rotor.
 

i12drivemyMP5

___ 323F ___
Contributor
The hell with stupid bulb clips for the h1 hids in the retrofit projector setup. Found the real solution from morimoto.......

59EB5275-D8FE-4727-B949-A9FF9E2E9EC3.jpeg
 

BenjiHoggi

OEM+
:
Oregon, USA
:
22v Protege5
Alas I am plagued by the common AC fan speed issue - no AC on anything but speed 1, not even a flicker. I've tried the resistor fix twice, with little success.

Another enthusiast recently pointed me toward this cool adapter, which supposedly fixes this problem. Anybody on here order one of them, or have any experience to speak of? Just wondering if this will work any better than my resistor hack. I'm no stranger to wiring, and don't want to spend money if it's a simple problem I can fix myself.

I've done lots of searching and reading on here, but haven't seen many other fixes worth trying. Feel free to throw them at me if I've missed them.
 
issues I need to address are...a couple of CEL codes.
Brought forward from your original list of things to do.

FWIW, these are like $18 from Amazon and install in a few minutes. If this doesn't clear the CEL, then you might also need to get a Charcoal Purge Valve (it's under the rear bumper).

This purge valve cleared my P0455 CEL-> Amazon - Vapor Cannister Purge Valve
Right now $11.99 with Prime Member 2 Day shipping.

It goes on the top of the air tube before the throttle body (photo attached below).
PCB had to lead me to it like a horse to water as the original valve was configured differently.
 

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