Coolant leaking, blown head gasket or else?

[DSlab]

The coolant in my P5 had been leaking. However, no visible leak under the hood, no murky oil when examining the dipstick. At first I just thought maybe it was the radiator cap or something, but I beginning to think it is an internal leak.

When accelerating from a stop I can hear water slushing sound under the dash. Also I see the coolant reservoir bubbling when checking the coolant level after a short drive. It smell like exhaust. Didn't see white smoke coming out of exhaust when I let it idle, but saw alittle bit today backing out of a parking space (I saw it when revving the engine a little too much when backing out).

So my question is, it seems to me a blown head gasket or cracked head, but could it still be something else? something to do with the intake manifold?

I bought the car in March and it has since developed so many problems. Although there are things to like about this car, I am really starting to regret the purchase:'(.

 

[bgibb68]

if you head gasket is blown you will know....check your oil when you change it....if you are leaking coolant internally it will show up on top of the oil when you drain it. shouldn't have anything to do with the intake, but there is a coolant line to and from the throtle body, what else have you had problems with.. i have had mine for 6 years, i'm over 103k and haven't had any problems 'cept other people hitting my BRIGHT yellow car that glows in the dark

edit: if the head gasket is blown you will hear it and have almost no power to drive with

 

[DSlab]

my other big problem is with the transmission. 5th gear pops out. actually it could be a expensive problem or might not, since I know our 5th gear is accessible by removing the black cover. Might be able to fix it without taking out the whole transmission

other smaller problems I had would be the annoying squeaking sound coming from the rear, and AC won't work on setting 2 and 3 (fixed this problem already after taking apart the AC switch).

the car also idles rough, been getting misfire code, and running lean. I thought it was the EGR, I've already ordered a new one but haven't received it yet in the mail. But now I am thinking the coolant leak and the rough idle are related.

Few month ago I had a burst upper radiator hose, I replaced the hose and thought everything was good, I guess I never really thought about the root cause of the problem or what other damages it may have caused.

I am not seeing any water/oil mixture on the dip stick or the oil cap. But just this week the car started losing some power when it is still cold. I have to rev up the engine to get the power back. But once it starts going it won't happen again until I stop the engine and let it sit for bit.

 

[DSlab]

Anyone knows how difficult it is to remove the cylinder head for our engine?

 

[justanothermp5]

not too hard, just take off the valve cover and then undo the head bolts...then it should come right up once u take off the intake and exhaust mani...
i wouldnt suggest it if your not very knowledgeable with cars though....might do more harm then good

 

[bgibb68]

Anyone knows how difficult it is to remove the cylinder head for our engine?

well test the compression before hand....it's time consuming from what i've heard but i wouldn't know....seems easy enough if ya know what your doing..

ac switch...me too and fixed.

rear squeaking probably the bushings on the sawy bar or your struts need to be replaced...

5th gear popping out could be bad mounts...i have 1 maybe 2 that are bad and my 5th is loose too hasn't popped out though..

was the hose you replaced the one with the thermostat? if so i know mine is leaking right there cause that seal ring they use is crap

 

[bgibb68]

rough idle is most likly the egr...had that problem and cleaned it and it's perfect smooth now

 

[DSlab]

yeah, I want to get a compression test done first. But now I am a bit afraid to drive the car around, worry that it might cause more damage.

Although I am learning, I am still not very knowledgeable. However, if it is really not that hard to take it apart, I might just find (or pay) someone that is knowledgeable to help me do it. I prefer not just take it to a shop and have some one take care of it, cause I want to learn something out of it. If not, maybe I can take it to a shop and ask if I can watch them do it (I know, I'm weird like that).

 

[bgibb68]

i'm the same way....next year i'm gonna hunt around and try to find a 2nd motor so i can rebuild it and still keep my car going

 

[SIBalla23]

If there is an internal coolant leak, the egr is not causing the rough idle and misfire. The coolant leak is. Seems to me the headgasket is on its way out. A compression check is a must. If you really want, pull out the spark plugs. You might find a wet spark plug in one of the cylinders and if you do then you know for sure its the headgasket. Also what is the misfire code?

 

[DSlab]

How would you diagnose the 5th gear popping out problem? How would you know if the engine mount is bad or linkage or something else? Is switching out the engine mount the only way to figure this out?

I actually took out the EGR and cleaned it following the instructions given here in one of the howto, but it didn't fix the problem . I also took apart the IAC and cleaned that (although it doesn't seem to be too dirty). I thought I destroyed the EGR by cleaning it too much. I thought that was the case because I sealed the EGR and blew smoke into it and found that it wasn't really air tight. I thought that should be the problem since It was running lean. However I also had doubt, cause I also replaced the spark plugs during that time frame. to make the long story short, I finally just ordered a new EGR cause I won't know if that is the problem until I put a new one on there.

The squeaking sound wasn't caused by the rear sway bar, because I took the sway bar off to see if that was the problem, but the squeaking persist. the sound actually seem to be coming from right below where the seat belt comes out. Anyway, this problem is currently not on the top of my repair list.

 

[DSlab]

the first misfire code I got was P0303 (3rd cylinder). After changing the spark plug I got P0300 (random) and then P0303 again. I think there are multiple problems with the car, it just makes the diagnostic process harder.

 

[DSlab]

By the way, I bought the car through this forum. It already had a built engine. The previous owner had a turbo in it for 5000 miles. Maybe that is why all these problems now.

 

[SIBalla23]

How many miles on car now? How much coolant you leaking on a daily basis? Were you losing coolant when you first started to get the misfire? Did you replace all or or just the 3rd cylinder plugs? What did they look like after you replaced them?

 

[aMaff]

is it spraying any coolant out the tail pipe? You won't *necessarily* have coolant in the oil w/ a head gasket leak. Check the plugs, see if one cylinder smells a little different or is really clean. If you're hearing water behind the dash, it may be the heater core, but you'd have damp carpeting as well.

 

[SIBalla23]

Is the turbo still in it now? How do you know you are lean? You have a wideband afr gauge or getting a cel for running lean? Also do you have a vac/boost guage in car?

 

[DSlab]

I say I probably add about 1 ~ 1.5 L of coolant daily now. Before I was just adding coolant once every few days or once a week. It is just this last 2 weeks that seems to start getting worst. Then again I didn't drive this car daily.

The car has 37300 miles on it now, when I bought it it was around 31500. The check engine light comes on occasionally few month ago, but then it would go out by itself. It would stay off for a while and then come back on again. I can't remember whether it happened before or after the upper radiator hose burst. Then I finally hook the car to a reader, and saw the misfire code. After that, I changed all the spark plugs (since they needed to be replaced anyway). I changed it to the longer plugs as suggested in one of the thread here, but then it started getting more rough, also got the random misfire code. So I replaced the spark plug again with shorter ones (new ones, not the ones I took out before), but the problem didn't go away.

The turbo is no longer in the car now. The previous owner parted out the turbo before he sold the car. I didn't get a cel telling me it was lean. I knew it was lean because I hook it up to a Snap-on Modis scanner, and used the emission probe (the thing that you stick into the tail pipe). At that time nothing seems to be out of the ordinary, just that it was running lean (to be honest, I wasn't quite sure what I was doing, someone just told me from the reading that it was running lean).

 

[DSlab]

Don't have damp carpet. And no white smoke when just idling. However, I did see some white smoke when I rev the engine while backing out of a parking spot today.

 

[DSlab]

This is my car:

http://www.mazdas247.com/forum/showthread.php?t=123695958

 

[DSlab]

Took off the valve cover and removed the spark plugs yesterday. Found coolant in the 3rd cylinder. yeah..... great thanksgiving.....

So at this point, would doing a compression test still benefit me?