HELP having code P0300 after getting the head rebuilt on my 2003 protege5

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2003 Mazda Protege5
Hello everyone,

I have an 2003 mazda protege 5. It was burning oil so my mechanic figured it was the valve stem seals that were damaged. he went ahead and rebuilt the head. After he put everything back together now the car has a harsh start. I got CEL with code p0300, so I figured i'd start by replacing the coils and the spark plugs along w the spark plug wires, however car still dying.

After doing some reading online my next option was to replace the EGR valve, which I've heard will cause the engine to stall out and misfire w the p0300 code. So I went to autozone and droped $140 to replace it, put it in this evening car is still drying, however the CEL has turned off.

It almost sounds like its sucking too much air in as it is making a weezing noise from the intake. I checked for any leaks past the MAF sensor and everything looks good. I noticed after starting the car a few times smoke started coming out of the catalyc converter which concerned me a little So i let the car cool down and just drove it back into the garage. At this point I don't know what to do, and I do not want to spend more money. Car is still smoking when I start it up.

from doing research online it leads me to believe the piston rings might be screwed but before the head rebuilt the car was running fine, it was just the burning of oil in the morning when I first start it up. car has 168k miles on it and is my daily driver.

I took video of the cars behavior and will put the links in as soon as I get the videos uploaded to youtube. Any advise/help/pointers are appreciated.
 
It's almost a guarantee that your rings are causing the oil consumption. Don't be surprised when it comes back.

I'd be very upset with the mechanic if he returned the car in that condition.

Spray some carb cleaner around the intake and injectors to see if there are any vacuum leaks. The engine will idle up if you spray the carb cleaner into a leak.
 
Thanks for your repply MrGiggles. Not the answer I wanted to hear but at this point I'm not surprised.

The mechanic is supposed to come by this saturday, I will post an update then.

I cleaned the Idle control valve last night in hopes that maybe this would fix something but to noavail. In fact the car feels like it got worse, soon as I cranked it wanted to stal out. cranked it a second time and it just stalled out on me. I gave up. Just waiting to see what the damage will be this weekend.

funny thing is that the car never overheated, and from what the mechanic told me as long as that had not been the case he expected the rings to be ok. furthermore I did compression tests on all cylinders and I was getting 170 readings across the board. But its one of those things you can't see til you take the damn thing apart.

btw my mechanic also mentioned that the engine this car has is the same engine found in ford rangers, made by ford? stumped me when he told me, I ask because I see that you have a ford ranger yourself.
 
Thanks for your repply MrGiggles. Not the answer I wanted to hear but at this point I'm not surprised.

The mechanic is supposed to come by this saturday, I will post an update then.

I cleaned the Idle control valve last night in hopes that maybe this would fix something but to noavail. In fact the car feels like it got worse, soon as I cranked it wanted to stal out. cranked it a second time and it just stalled out on me. I gave up. Just waiting to see what the damage will be this weekend.

funny thing is that the car never overheated, and from what the mechanic told me as long as that had not been the case he expected the rings to be ok. furthermore I did compression tests on all cylinders and I was getting 170 readings across the board. But its one of those things you can't see til you take the damn thing apart.

btw my mechanic also mentioned that the engine this car has is the same engine found in ford rangers, made by ford? stumped me when he told me, I ask because I see that you have a ford ranger yourself.
 
... I did compression tests on all cylinders and I was getting 170 readings across the board. But its one of those things you can't see til you take the damn thing apart...

Our engines have a problem with seized oil rings,... The compression is almost always fine.

Screenshot_2016-06-11-00-32-40_zpsaoywbsuj.png



https://www.mazdas247.com/forum/sho...n-cold-start&p=5504992&viewfull=1#post5504992
 
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There's an easy test to find out...

Let your car sit overnight then remove the plugs and look down the holes.
If the pistons are wet with oil it came from the valve seals.

Put your plugs back in and crank your engine for about 20 seconds and shut it off.

Pull the plugs again and check for oil again on the pistons.
If they are wet, the oil got past the oil rings.
 
Thanks for your repply MrGiggles. Not the answer I wanted to hear but at this point I'm not surprised.

The mechanic is supposed to come by this saturday, I will post an update then.

I cleaned the Idle control valve last night in hopes that maybe this would fix something but to noavail. In fact the car feels like it got worse, soon as I cranked it wanted to stal out. cranked it a second time and it just stalled out on me. I gave up. Just waiting to see what the damage will be this weekend.

funny thing is that the car never overheated, and from what the mechanic told me as long as that had not been the case he expected the rings to be ok. furthermore I did compression tests on all cylinders and I was getting 170 readings across the board. But its one of those things you can't see til you take the damn thing apart.

btw my mechanic also mentioned that the engine this car has is the same engine found in ford rangers, made by ford? stumped me when he told me, I ask because I see that you have a ford ranger yourself.

He's full if it. The Mazda FS is not related in any way to the Ford Lima 2.3/2.5 from 00 and older Rangers or the 2.3 Duratec in 01 and newer.

The FS did come in the Ford Probe though.

The photos that PCB posted is from my old engine that ran perfectly and had great compression, just smoked like crazy in the morning.
 
The photos that PCB posted is from my old engine that ran perfectly and had great compression, just smoked like crazy in the morning.

If you get your car running again, you may want to just ignore the smoking.

A ring job is pretty involved and expensive.

Apparently switching to dino oil reduces the burning a lot, as well as a thicker oil like 10W30.
 
To update,

My mechanic has flaked on me twice this weekend. Car still in the garage and keeps stalling out.
I managed to clean out the ICV but that didn't do anything. However in the process the 4 Phillips screws that hold it down got completely stripped and next time I need to take it out Im certain I'm gonna have to use a dremmel to slot them out.

Car still smokes when I crank it so I'm almost certain the Piston rings are friend.

Having said that does anyone know or can recommend a good shop for this kind of job in the southern California area? My zip code in 91107. Any help would be appreciated.
 
yet another update,

mechanic came by today while I was at work. He worked on the car and it turns out one of the injectors was dirty. He took fault for this and appologized. Car seems to be running fine now except that it is still smoking a bit from the engine which he said is the leftover oil it had been burning. He advised me to take the car on the freeway and slowly it should stop smoking over time. Fingers crossed I hope he's right.

Now for something new, when I downshift as the car slows down I hear a ratle. the noise was there before but I want to say it might of got a little more amplified or I'm just paranoid of anything I'm hearing from this car. Has anyone heard this noise I speak of? One of my friends who also drives stick mentioned all manual cars make this noise. I just wish I knew where it comes from of if something needs to be tightened to get rid of it. Any experience is appreciated. I will try to capture this sound on video and post on here.

At this point I think I'm just going to drive the car for the time being until another problem comes up, also I'm out of money and a ring job is completely out of the question for now.

I manged to take a couple of pictures when the head was off. check out all the oil build up in the mnifold and the piston heads.
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I don't think Seafoam is gonna help you at this point.
Oil is probably constantly getting past the oil rings and up on top of the pistons.
Your mechanic probably thinks he fixed the oil burning problem but it's probably the rings.

Seafoam in the oil could possibly help clean up the rings and keep them moving but some guys were burning oil at the rate of a quart every few hundred miles.

Some guys were completely fogging out their entire neighborhoods for ten minutes every morning.
Burning at that rate starts getting expensive, especially with Seafoam in the oil.


I think you should stock up on cheap 10W30 dino oil, keep it in your car and get in the habit of checking your oil every 1 or 2 hundred miles.

Just run your car until your mirrors are useless because all you see is white and you start getting pulled over by the fire department...
By then, you may have saved up enough money for a ring job.
 
^What he said :)

FYI, I just took my IACV off last weekend using a new #2 JIS screw driver and went 4/4 no stripping. They all were crazy tight and went *CRACK* when they busted loose, but no damage to the fittings on any of the screws.
 
wish I had known this prior to stripping all 4 screws:(. The only way I can think of taking off those screws now is by cutting a slot w a dremel attachment. But that also seems a little risky since the fuel rail is right next to the ICV. Any suggestions on how to get those 4 screws off? vice grips will not fit as the valve is at an angle. I alread tried the screw extractor but that didn't work. any links to any tools would be appreciated. thanks all!
 
Maybe get the proper screwdriver and try,.. You've already had them off so you shouldn't have to crack them free again.
Other than that, all I can think of is your dremel tool... Carefully.

If you do get them off, you should replace them with little bolts from a hardware store.
 
If you lean right in there and don't smell any gas, then you should be quite safe to dremel, even if you spray a few sparks.
As long as you don't cut into the fuel rail...
 
If I was in that situation I would remove the whole throttle body. 4 bolts and a few plugs, unhook the throttle cables.

A lot of damaged screws can be loosened with a couple taps in the loosening direction from a chisel on the outside edge.

JIS or not, Phillips should have never been as popular as it is. Nothing but a pain in the ass.
 
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