While replacing the rear motor mount, I noticed that exhaust gases would be seeping out of the gasket between the j-pipe and the second catalytic converter. It was also noisy. I finally got around to replacing the donut gasket, but it is still loud. I re-used the existing springs that go on the bolts (connecting the j-pipe and catalytic converter flange) with new bolts and nuts. Maybe that's the issue. A couple of seconds after I start up the car, I see water dripping out of the gap where the donut gasket is. So, if it isn't water-tight, it isn't air-tight. The next step I am going to do is is get new springs and use exhaust gasket sealant too.
exhaust gasket issue, donut gasket
- Thread starter rit14623
- Start date
- :
- -- 03 P5 / 23 CX-5 --
New springs maybe but sealant would be waste IMO. Has this area been damaged in any way or are the hangers on the midpipe OK? That donut shouldn't have any problem sealing that up.
MazdaSpeeder
Member
- :
- Protege5 (5-spd)
Did you tighten it to the specs found in the service manual? IIRC, new springs aren't too much from Mazda. There shouldn't be an issue with the seal, so my guess is it either isn't tight enough or you need to replace those springs.
Installshield 2
Gothenburg Superiority
Were the flanges ok? Or rusted through? Agree with the others, unless that gasket is the wrong size there should be no sealing problems.
The flanges seemed to be okay upon visual inspection.
The hangars on the midpipe are okay. It's not sagging, and they provided quite the amount of resistance to hold it away while I took out the old donut gasket and put in the new one.
Gasket was a Bosal to fit OEM j-pipe.
The old donut gasket seemed to be eaten away from the outside edge facing the j-pipe, which is the side exposed and not touching the catalytic converter's flange.
I tightened the nuts down on the springs more than it was before I changed out the gasket, i.e. the springs were more compressed. I got new Bosal springs coming. I saw some generic exhaust flange springs at Advance AutoParts but they were not the same size.
The hangars on the midpipe are okay. It's not sagging, and they provided quite the amount of resistance to hold it away while I took out the old donut gasket and put in the new one.
Gasket was a Bosal to fit OEM j-pipe.
The old donut gasket seemed to be eaten away from the outside edge facing the j-pipe, which is the side exposed and not touching the catalytic converter's flange.
I tightened the nuts down on the springs more than it was before I changed out the gasket, i.e. the springs were more compressed. I got new Bosal springs coming. I saw some generic exhaust flange springs at Advance AutoParts but they were not the same size.
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- -- 03 P5 / 23 CX-5 --
Not that this helps the immediate problem but having a flex fitting on the midpipe relieves some of the stress on that donut and the manifold, to a degree, from the jostling around the exhaust does from normal driving, hitting bumps, engine vibrations when starting and such. I had one added when I made up a hi-flo catted midpipe after header and cat-back were installed. I used the factory flange/springbolts off the oem midpipe that attach to the header where that donut goes then bigger piping to flex, cat and catback. Have had no issues with that oem donut in 8 yrs or so.
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Hmm, so I thought I was getting a pair of springs, but only one came. My mistake. So, I installed it and cranked down on the other one with the old spring. Now, no condensation/water drips out of that connection. But, it is still loud. So, I can't find the leak but it's somewhere near the front. It's either the j-pipe or second cat piping that has a hole. I can't see it though.
That flex tube idea sound good. I've replaced exhausts on previous cars I've owned and I kind of wonder why this car doesn't have a flex tube section. So, while working on the motor mount awhile back, I pressed up on the exhaust pipe just to see how much flex there was with the springs, so it flexed, after that, the exhaust sound got much louder. If you have a flex tube, I don't see a need for springs, you could just use bolts, washers and nuts to connect the j-pipe and second catalytic converter that has a flex connection.
That flex tube idea sound good. I've replaced exhausts on previous cars I've owned and I kind of wonder why this car doesn't have a flex tube section. So, while working on the motor mount awhile back, I pressed up on the exhaust pipe just to see how much flex there was with the springs, so it flexed, after that, the exhaust sound got much louder. If you have a flex tube, I don't see a need for springs, you could just use bolts, washers and nuts to connect the j-pipe and second catalytic converter that has a flex connection.
Well, I replaced the J-pipe. The Bosal one came with a donut gasket on it already so that was nice. Replaced the old one. The OEM one is cast iron. No holes in it. That didn't solve my problem. I put on exhaust sealant on it and that didn't work either. The leak is elsewhere. I feel pretty dumb and I've dropped about $100 on parts. I need to fix it because I have to get it inspected.
Has anyone ever had issues with the exhaust manifold gasket leaking? Most of the volume of the engine seems to come from somewhere in the engine bay.
Has anyone ever had issues with the exhaust manifold gasket leaking? Most of the volume of the engine seems to come from somewhere in the engine bay.
danielschweer
Member
- :
- '02 protege5
have you checked around the EGR tube? i recall having a small leak there at one point.
No, I haven't checked around the EGR tube. I did remove and clean the EGR over a year ago.
Three things to note:
1. the cylinder head is very greasy below the valve cover. It wasn't always greasy so I don't know if the valve cover gasket is leaking.
2. There is no leak of exhaust or sound coming from the second cat and back to the tailpipe.
3. Most of the sound is coming from the front of the engine. I didn't take off the exhaust manifold shield.
Three things to note:
1. the cylinder head is very greasy below the valve cover. It wasn't always greasy so I don't know if the valve cover gasket is leaking.
2. There is no leak of exhaust or sound coming from the second cat and back to the tailpipe.
3. Most of the sound is coming from the front of the engine. I didn't take off the exhaust manifold shield.
Did that leak cause a loud exhaust? What did you to do fix the leak? New gasket? Where was the leak exactly?
So I disconnected the nuts to the pre-cat and took out the gasket that goes between the exhaust manifold and the catalytic converter and found three metal gaskets. One was thicker than the others (this piece was almost 1mm thick) and the other two were very thin (together, they were less than half of 1mm). The two that were very thin had two breaks in the same areas. If you look at the gasket as a circle with five holes, there was a one inch section of the circle that was completely broken off at one of the holes.
I didn't have a replacement as I didn't know what the source of the sound was and I was trying to pinpoint it down. I had to put it back together because I needed to drive it. I put some exhaust sealant on the broken gaskets to "glue it" back to the one solid gasket piece and reinstalled it.
I'm still getting a loud exhaust sound from the engine bay and confirmed that there is no leak or sound coming from the donut gasket anymore. I'm thinking of removing the rear motor mount inserts as they seem to have exacerbated the whole exhaust sound problem.
I didn't have a replacement as I didn't know what the source of the sound was and I was trying to pinpoint it down. I had to put it back together because I needed to drive it. I put some exhaust sealant on the broken gaskets to "glue it" back to the one solid gasket piece and reinstalled it.
I'm still getting a loud exhaust sound from the engine bay and confirmed that there is no leak or sound coming from the donut gasket anymore. I'm thinking of removing the rear motor mount inserts as they seem to have exacerbated the whole exhaust sound problem.
Installshield 2
Gothenburg Superiority
Is there a way you can have someone else drive the car around a parking lot for you? While you stand and listen? It can be very difficult to determine what is an actual exhaust leak sound, or just 'engine' sound coming into the cabin...Like you mentioned, when i installed stiffer engine mounts the interior engine noise was dramatically increased...but outside the car you'd never know anything was changed...
the original leak you had is fixed? You mentioned water coming out of the spring mount...and its not doing that any more?
the original leak you had is fixed? You mentioned water coming out of the spring mount...and its not doing that any more?
I'm getting a new gasket to replace the broken one. When I'm idling in park, it is loud. When I'm idling in neutral, it is quiet. I'm going to replace the front motor mout and not install the motor mount insert and I'm going to remove the rear motor mount inserts.
I did a lot of maintenance and repair this weekend. Spent about 8 hours on Saturday and 4 hours on Sunday.
- I replaced the catalytic converter gasket between the exhaust manifold and catalytic converter; and replaced four of the five bolts (FYI, M8 - 1.25). One of the double ended screws stayed in but the nut came off so I replaced the nut on that. Side note, the 12-point sockets seem to strip the nuts. Two got partially stripped so I pulled the exhaust manifold and cat off together as one piece. I used a 6-point 1/4" socket to get those two screws off.
- I replaced the gasket between the catalytic converter and the j-pipe; and replaced two of the three bolts (FYI, M10 - 1.5). I replaced the nut (FYI, M10 - 1.5) holding the pre-cat to the engine mount bracket because I had to cut it up to get it off. I actually had to remove the engine bracket-to-engine bolt to get the catalytic converter off. The exhaust volume has dropped and it sounds like a normal car again.
- I replaced both O2 sensors. Both were last replaced for over 80,000 miles
- I replaced the valve cover gasket. It wasn't torn anywhere but oil was leaking out onto the cylinder head and was getting down to the exhaust manifold gasket. The exhaust manifold gasket wasn't blown but had oil on it so I cleaned it off and reinstalled it. In the process, I've removed the exhaust manifold cover which was rusting out so I didn't put it back on.
- I cleaned and regapped the spark plugs.
- I replaced the front motor mount. I took out the old one and the motor mount inserts. The Dea-brand front motor mount has a beefier inner rubber section than the OEM one so you can't use the motor mount insert if you wanted to.
- I took out one of the rear motor mount inserts and kept the right side one in (just an experiment). There a lot less vibration now.
- I tightened the alternator drive belt since it was loose (I was getting occasional belt squealling).
- Just when I was at a stop on the drive home on Friday, I had major idle problems. So, I cleaned out the throttle body with throttle body cleaner (I don't know if this is better than carb cleaner or not). And then, I cleaned out the IACV wth throttle body cleaner. That was not easy. I stripped three of the four phillips screws so I had to get a screw extractor and replacement screws (FYI, M5 - .8). When I got it off. I cleaned it out, but I couldn't remove the valve controller side (black cylinder-shaped thing) because there was a point in the middle of the Torx screws so you can't insert a Torx screwdriver. I guess to prevent removal by grease monkeys. I put the IACV back on; I still had some issues with idling, but I think it is because I didn't run it at idle for awhile. So, I ran it at idle for a couple of minutes this morning and it got better but instead of running smoothly at one RPM, it is pulsing in between 600 and 800 RPM.
- I replaced the catalytic converter gasket between the exhaust manifold and catalytic converter; and replaced four of the five bolts (FYI, M8 - 1.25). One of the double ended screws stayed in but the nut came off so I replaced the nut on that. Side note, the 12-point sockets seem to strip the nuts. Two got partially stripped so I pulled the exhaust manifold and cat off together as one piece. I used a 6-point 1/4" socket to get those two screws off.
- I replaced the gasket between the catalytic converter and the j-pipe; and replaced two of the three bolts (FYI, M10 - 1.5). I replaced the nut (FYI, M10 - 1.5) holding the pre-cat to the engine mount bracket because I had to cut it up to get it off. I actually had to remove the engine bracket-to-engine bolt to get the catalytic converter off. The exhaust volume has dropped and it sounds like a normal car again.
- I replaced both O2 sensors. Both were last replaced for over 80,000 miles
- I replaced the valve cover gasket. It wasn't torn anywhere but oil was leaking out onto the cylinder head and was getting down to the exhaust manifold gasket. The exhaust manifold gasket wasn't blown but had oil on it so I cleaned it off and reinstalled it. In the process, I've removed the exhaust manifold cover which was rusting out so I didn't put it back on.
- I cleaned and regapped the spark plugs.
- I replaced the front motor mount. I took out the old one and the motor mount inserts. The Dea-brand front motor mount has a beefier inner rubber section than the OEM one so you can't use the motor mount insert if you wanted to.
- I took out one of the rear motor mount inserts and kept the right side one in (just an experiment). There a lot less vibration now.
- I tightened the alternator drive belt since it was loose (I was getting occasional belt squealling).
- Just when I was at a stop on the drive home on Friday, I had major idle problems. So, I cleaned out the throttle body with throttle body cleaner (I don't know if this is better than carb cleaner or not). And then, I cleaned out the IACV wth throttle body cleaner. That was not easy. I stripped three of the four phillips screws so I had to get a screw extractor and replacement screws (FYI, M5 - .8). When I got it off. I cleaned it out, but I couldn't remove the valve controller side (black cylinder-shaped thing) because there was a point in the middle of the Torx screws so you can't insert a Torx screwdriver. I guess to prevent removal by grease monkeys. I put the IACV back on; I still had some issues with idling, but I think it is because I didn't run it at idle for awhile. So, I ran it at idle for a couple of minutes this morning and it got better but instead of running smoothly at one RPM, it is pulsing in between 600 and 800 RPM.
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Installshield 2
Gothenburg Superiority
did you disconnect the battery for all this work? If you did, thats the idle problem. It takes a good hundred miles or so for the ecu to cache some closed loop data, which is used for idle...very normal for a bumpy idle when the ecu has been reset...it'll go away...
I disconnected the battery.
This morning was all bad news. The exhaust sound is back to normal. I don't know what happened. I haven't had a chance to look at where the exhaust leak is. Last night, the idle sometimes is rough and sometimes it will stall out; and now, starting takes a couple cranks instead of immediate start up.
I got a code reader yesterday. I never got a check engine light until last night when I was idling at a stop light. It came out to be P0300 which is random misfire. This morning at the end of my commute, I let the car idle in the parking lot and it was revving around 600 instead of stalling out or dropping down to 300 RPMs. I've already cleaned out the IACV and throttle body. I'm going to spray carb cleaner around the intake manifold and throttle body.
I saw online that low fuel pressure due to a clogged fuel filter is one possible cause of P0300. I haven't changed my fuel filter since I've owned the car. I don't know if that is related to low fuel pressure. I don't have a tool to check pressure. I'm going to check the EGR too if something is blocking the valve by some odd chance. My plugs, wires and coils are fairly new.
This morning was all bad news. The exhaust sound is back to normal. I don't know what happened. I haven't had a chance to look at where the exhaust leak is. Last night, the idle sometimes is rough and sometimes it will stall out; and now, starting takes a couple cranks instead of immediate start up.
I got a code reader yesterday. I never got a check engine light until last night when I was idling at a stop light. It came out to be P0300 which is random misfire. This morning at the end of my commute, I let the car idle in the parking lot and it was revving around 600 instead of stalling out or dropping down to 300 RPMs. I've already cleaned out the IACV and throttle body. I'm going to spray carb cleaner around the intake manifold and throttle body.
I saw online that low fuel pressure due to a clogged fuel filter is one possible cause of P0300. I haven't changed my fuel filter since I've owned the car. I don't know if that is related to low fuel pressure. I don't have a tool to check pressure. I'm going to check the EGR too if something is blocking the valve by some odd chance. My plugs, wires and coils are fairly new.
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Installshield 2
Gothenburg Superiority
wow, sorry man...
How many miles are on the car?
everyone hates p0300...most of us have been there...
common causes:
Plugs/wires/coils needing replaced
EGR malfunction (but computer still thinks its working)
EVAP system malfunction
Fuel pump/filter/pressure regulator
Vacuum leak (unlikely though, as there are other codes that will often show up with that)
cylinder head gasket...other signs will point to that though, so also unlikely
You're sure you hooked up your o2 sensor properly, right? You didn't accidentally switch the primary and secondary connections? That can cause a p0300 after warm up, too...but its often mixed with a 'too long for closed loop switch' code as well...and a few o2 sensor threshold codes...
How many miles are on the car?
everyone hates p0300...most of us have been there...
common causes:
Plugs/wires/coils needing replaced
EGR malfunction (but computer still thinks its working)
EVAP system malfunction
Fuel pump/filter/pressure regulator
Vacuum leak (unlikely though, as there are other codes that will often show up with that)
cylinder head gasket...other signs will point to that though, so also unlikely
You're sure you hooked up your o2 sensor properly, right? You didn't accidentally switch the primary and secondary connections? That can cause a p0300 after warm up, too...but its often mixed with a 'too long for closed loop switch' code as well...and a few o2 sensor threshold codes...
a little over 159,000 miles
I hooked up the upstream and downstream O2 sensors properly. I started getting the idle issues before I replaced the O2 sensors. I thought I would replace them both as a matter of general maintenance rather than repair. And, I did worked on each O2 sensor to avoid accidental swapping of connections.
