White smoke on cold start... Diagnose my car! Go!

Coqui258

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2003 Black Mica Protege5
Hi everyone! I haven't posted on here in forever, but I am having issues with my car that I'm hoping someone can help. As a preface, I'm no newbie to our beloved Protege5. I have done almost all repairs and maintenance myself.

2003 Protege5, 120k miles, synthetic oil (Mobil 1 10w30 since I bought it), Manual T/M, new timing belt @ 100k miles

Symptoms: White smoke (not condensation) on cold start which started months ago, then went away. Over the summer noticed that my oil level was going low fast... coolant never goes down. About 2 months ago, it was so harsh that it was embarrassing to start the car after it sits for a long period of time. Smoke lasts for about 10-15 seconds and sometimes lingers until the car warms up a little. When warm it's completely gone.

Fix #1: Had a Felpro gasket set which included valve stem seals so went ahead and replaced the seals. Definitely noticed a pool of oil on the #1 cylinder head through spark plug hole. I did it without removing the head (rope trick, works awesome), and changed out the water pump while I was there. Also changed the PCV valve and made sure vacuum hoses were secured. First morning, still smoked. Used Seafoam and it stopped smoking for a few days, then slowly came back.

Diagnosis: Bought a compression tester, had 185-190 in all cylinders. Oil still drying up, coolant still the same. Smoke is mostly white and thick. Smells funky.

Fix #2: Read up that the stem seals do need a little "light hammering" when installing them, so I went back in again and made sure they were secured by giving them a light tap. Put it all back together and still have the smoking.

Fix #3: Read up again that the intake and exhaust seals are actually different in size, and the Felpro set had 2 different colors for their seals but I didn't know which went where. Bought new intake and exhaust seals and went back in AGAIN to change them out. Installed them with some assembly lube and lightly tapped them into place.

Fix #4: Read that synthetic oil can make cars with 100+k miles can make smoking worse due to its thin nature, replaced the oil back to conventional oil (10w30) and added a can of restore to see if it will help.

Still smokes like a chimney! I'm close to opening her up and changing out the valves, guides, and O-rings... but don't want to make this repair if unnecessary. So, what are your thoughts?

- EGR valve? (read up somewhere that it could cause the smoke?)
- Guides, valves?
- O-rings?
- Compression rings?
- Head gasket?
- Cracked head?

Any help is appreciated!
 
I started to read that post this morning (first time seeing it, surprised it didn't come up in search before), and it's not very easy to follow since there are tons of "maybes". I'm thinking rings too.
 
I started to read that post this morning (first time seeing it, surprised it didn't come up in search before), and it's not very easy to follow since there are tons of "maybes". I'm thinking rings too.

Just got a P0303 code for misfiring cylinder #3. Got it when I accelerated hard to see if smoke was still coming out after driving for 10 minutes. Just ordered new plugs and wires and a new EGR valve. Let's see if this does the trick.
 
Oil rings on your pistons...

To find out, pull each sparkplug and shine a light down the hole and look for oil on top of the cylinders. Check before a cold start. Reinstall the plugs.

Start the car, run it for twenty seconds, stop the car and check the plug holes again.

If they are now soaked in oil then you have stuck oil rings.

(Very common for our cars....)
 
Just got a P0303 code for misfiring cylinder #3

You probably have all kinds of carbon crap (half burnt oil) on top of your cylinders increasing your compression and causing a misfire..

She's real dirty now...
 
@Coqui258... LOL well I wrote that thread. Might be hard to follow, but picture you looking for answers to various issues, solving some, encountering others and trying to get to the bottom of the real problem. Well, that was me. So I tried various things - don't waste your time with the valve stem seals - and posted the results.

What colour is your startup smoke? If you're getting white smoke at startup, it could be the gasket around the IAC valve - very common issue. If you read the thread, you will see it took some troubleshooting and investigation - everyone was saying it was a head gasket - to find the answer. And even the new gasket leaked a little, so I ended up putting a very light skim of silicone - only around where the coolant ports between the IAC valve and the throttle body mating surfaces.

If you're losing lots of oil, and you don't have leaks, check the pistons as pcb suggested. If you decide to do an on-the-car ring job, there is a link to that thread in my thread, as well as some corrections to the instructions. And lots of pictures... I tried to give as much detail as possible, but if you don't like detail, well, there's always awesome photos... ;)

Anyway, I'm not smoking any more.
 
LostinCanada, I did read through your whole thread when I was contemplating what to do about my car. Sucks that I wasted so much time with the seals, but at least I know they're new. It's definitely more white than blue smoke, and it's mainly on startup. BUT, recently I noticed that if I drive after the smoke, it still smokes a little until the car is more warmed up. I'm thinking this could be more of a coolant issue, but my coolant level stays the same and my oil does get consumed quickly.

I recently bought a new EGR valve and replaced it... hoping that it was that. Nope. I also changed my plug wires cause I pulled a CEL that said misfire on 3rd cylinder. The CEL hasn't come back yet...

So the IAC valve can be a possible fix huh? I'd rather figure out smaller fixes than go straight for the head gasket or oil rings...
 
You sure it's not just steam? It's getting to be that time of year again. How old is your thermostat?

I've never seen oil smoke that was white, and cars that burn oil typically consume it at a rate of 1 quart per 1-500 miles. If it was burning coolant, it would consume it as well. Have you checked the radiator level, or just the reservoir? Caps fail and sometimes won't pull coolant from the reservoir.
 
I have a 2001 2.0 and every now and then it smokes (white) really bad at start up. Rarely though.

Based on that link in the thread.....I'm leaving it until the darn thing dies. :)
 
@Coqui258 the IAC gasket is an interesting one because it presents a lot like a leaky head gasket. This turned up by accident when I changed my search terms after discovering the coolant signs in the throttle body and wondering how the heck it got there. Found it first on the Mazda 626 forum - I think it was that DJDevon guy who has posted a lot of stuff on his project car - some quite useful, some funny. At any rate his gasket was a bit different than ours, but it's the same problem. So early on in my saga I posted the page from the service manual and photos of the throttle body - it's quite a common problem, but not obvious unless you know what to look for.

It's a $5 gasket so not a huge expense, and never hurts to put new rubber in an old engine. Just don't be disappointed if you still have smoke!

You have to pull the throttle body - don't try to do it on the car... just ask that DJDevon fellow... lol. Definitely use an impact screwdriver on the screws - you don't want to strip those suckers and have to deal with it. And new screws from Mazda are like $4 ea. My new gasket still leaked intermittently even though the screws were good and tight. So a very light skim of silicone solved this issue. Interestingly, I had to use the impact screw driver when I pulled it apart the second time.

BTW all the while this was going on, I never noticed any fluid loss. In fact I've never had to add coolant until I drained/flushed the system.

Keep us posted!
 
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I was just watching a YouTube video of a guy removing his 626 head and all the parts associated with it... ugh, so much work, especially since I did the seals 3 times! I really don't think it's my head gasket. It would smoke all the time if coolant was constantly getting into the cylinder.

I already ordered the gasket... gonna see if that does anything. Then it's head gasket and possible O-ring time!
 
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