Protege 5 engine running rough despite repairs

W

woodman

Member
Ok I bought my 2002 Mazda Protege 5 second hand six months ago. It has about 140,000 km's on it (give or take). Sometime in August, the engine would suddenly start running very roughly (growwwwllllll) while I was driving around, with a definite loss of power. I learned to overcome this by putting it in neutral (while still moving - ack!), taking my foot off the gas pedal so the revs dropped, and pumping the gas pedal a few times whereby the car would magically come to its senses and rev properly again. Back into gear and off I'd go. Ultimately the engine light came on (and stayed on), so I took it to a garage. They read the code and assured me a tune-up would do the trick. They changed the spark plugs and the wires, did an oil change to boot, and off I went.

The problem disappeared and I naively assumed it was fixed. Not so. About 3 weeks later it returned - same problem - and became more and more frequent, to the point where it would occur when I was idling at stop signs to the point of almost stalling, as well as when in motion. Got harder to bring it back to its senses by pumping the gas pedal. Took it to another garage, they read the code, and changed the 2 spark plug coils.

Ok, so that MUST have fixed it, right? Well ...maybe. The "old" problem hasn't recurred, but now it seems to have a new (but similar) one. It's been about 6 weeks since that last repair and today I start up the engine, back it up a few feet, put it in 1st gear and before I even bring the clutch in it starts revving in a very peculiar way; sounds different from before, but same basic idea - throaty growl with loss of power. Pumping the gas pedal did nothing to solve my problem. Turned it off, started it again => same problem. I think you can imagine the expletives emanating from my mouth as I re-parked the car and took the bus for the day.

I checked my car this evening => turned ignition expecting same throaty unhappy grumble => purrs in sweetness at me.

So, wtf is going on?? I have read about those "EGM control valve" problems, but is there a Protege 5 expert out there who can help to diagnose this? If it is the EGM valve, then I don't understand why changing the spark plugs, wires + coils would have solved the problem so definitively in the past, yet on such a temporary basis, given that I don't think any mechanic has ever touched my EGM valve.

Thanks for any advice you can provide. I have resigned myself to yet another trip to the garage, but I would rather point the mechanic in the right direction as opposed to having the grease monkey plug it in to the computer and tell me with confidence the the error code will solve all my problems. They did that twice already and it hasn't helpled me much. Clearly they don't want to work too hard at solving my problem. Thanks for listening to my rant!
 
Sounds like you had coil issues & now you have a dirty EGR. As was stated above, check out the how-to & clean it yourself. You'll need 1/4 inch drive ratchet to get to the 2 bolts because of tight fit but it's doable, just don't lose the metal gasket when you get it off to clean it. There's a service manual stickied in here to for more info on the process.

http://www.floptical.net/mazda/
 
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Yeah, it sounds like the EGR valve. I know i'll get some flak for it, but I recommend that you replace the EGR valve, they have a new redesigned one. A mechanic should be able to buy a new EGR valve from Mazda and do the work for under $250.

BUT, make sure you read the code first. Any Autozone will do it for you. They have a small reader that they'll connect to a port under your steering wheel, very simple for them to do.
 
Replies

Thanks for the replies guys! Ok my first question is, do you think the process of cleaning the EGR valve is too much for a lunkhead like me? Or is it actually really simple? I mean, I have a few tools and I'm pretty sure that bolts are screwed on clockwise - that amounts to most of my experience. I changed my car battery recently and considered that quite an accomplishment. If there are some really (and I mean REALLY!) detailed instructions somewhere and if y'all think I can handle it, I'll give it a shot. (eek2)

Re: Autozone: any idea how much they charge to produce the engine code? Most shops charge anywhere from $40 - $85 to read the code.

Finally, I contacted a Mazda dealership and they quoted me $350 (Cdn of course) for the EGR valve part plus 2 hours of labour to replace it. Madsmartguy, you indicated it should cost around $250 for part + labour for the whole thing. Can you recommend where I can go to get it done for that price? Clearly I'm being suckered (as usual).

Thanks again! I really appreciate your advice.
 
Okay, yeah, the autozone will do it for free. Don't pay 50-70 dollars for the code, at that price, you can get a quality code reader yourself. I think for 50-70 they claim to do a diagnostic, which is a ripoff, you don't need that, you need your code read. Ask friends and coworkers, you'd be amazed how many people have them.

Umm, its not that easy of a job. I had a little trouble but I don't have much auto repair experience. There are two bolts facing up, so you have to reach and unscrew bolts that you can't see. The problem is that it's a tight fit, and you need the right tools. I was using a regular wrench, and I didn't have any room to move the wrench.

Call up Mazda dealers in your area and ask how much they will charge for the EGR valve, they should charge 170, but that's american dollars. The dollar is weak though, so maybe you can order on the internet.
It's definitely not two hours labor. It's closer to a half hour if you have the tools. Reasonably, they can charge for an hour i guess. So an hour of labor at around 60, plus 170 for the part totals 230. I would give the guy a good tip so he will want to do a good job next time you have any problems.

Generally though, ask friends and family for a mechanic that they go to. That way, you say so and so recommended me. If they overcharge you, they risk losing a number of customers, and not just a random guy off the street.
 
Problem still unsolved and giving me grey hairs

Ok, I had a mobile mechanic come by today and pull the code off of the car. The error code was P0300 / some sort of random misfire code. He confidently stated that it must be the crank position sensor ("the one at the bottom of the engine"). I went and hunted one down (no easy task), bought it and he installed it, and guess what? Exact same problem.

So now I've had the spark plugs, spark leads, 2 coils, and the crank position sensor all changed and the problem persists. I can start the engine with difficulty, but it is clearly not happy and the engine light blinks on and off, giving the same P0300 code. All of this occurred when the temperature dropped below 0 degrees celcius last week. I am becoming seriously disheartened; I can't even drive this thing out of my driveway. Advice?!
 
Although you have similar symptoms, the root cause of the problem might be different now from before. It is going to be hard to know, especially the previous mechanics never told you what code you had before, and never told you why they think a tune up would solve the problem. Anyway, at least you know now that you have a random misfire, we'll just start from scratch.

Basically there are 3 general cause to misfire: 1) Ignition problem (lost of spark) 2) Air/fuel mixture problem 3) loss of compressions.

Read here for more details:
http://www.aa1car.com/library/misfire.htm

I am not going to say the problem is with EGR or your spark plug or your wire or your coil or whatever. Because the first thing you need to figure out is which of the above 3 are the main cause to your misfire.

A leaky EGR is a Air/Fuel mixture problem. When the EGR gets stuck open, more air are leaking in causing a bad mixture for combustion. People here often suggest that as the cause to a misfire because EGR failure is a common thing with our car. It gets damaged by moisture in the air and get stuck. Mazda have since revised the EGR, so if you purchase a new one, it would most likely be a revised version. Replacing the EGR is not hard, although the space around that area is quite cramped, definitely helps if you have small hands. And of course the having the right tools is helpful too.

If you had a misfire before you took it to the first mechanic, and they changed your spark plugs and wires, then I guess they thought it was a ignition problem. Whether that is a correct diagnosis, we won't know, but I guess they are professionals and I assume they know what they are doing.

There is also a slight chance that you had multiple cause to your misfire problem. In that cause, the previous mechanic might have fixed one problem but not the other(s).

So what do you do now? Well, like I said, first figure out which of the 3 is causing the problem. A good mechanic will run through a series of test to narrow down the cause. (when it comes to misfire, often Inexperience mechanics and hobbyist/amateurs will tell you it is a ignition problem without running a bunch of test, ask many questions to make sure they did run through some thorough tests). Once you figure out which of the 3 are the cause, then it would be much easier to narrow down to the specific faulty part(s).

BTW:
1. Does the car runs more rough when it is warm or cold?
2. Did the CEL came on when the car is idling or when it was at a higher RPM?
3. Are you losing coolant?
 
woodman said:
They changed the spark plugs and the wires, did an oil change to boot, and off I went.

The problem disappeared and I naively assumed it was fixed. Not so. About 3 weeks later it returned - same problem - and became more and more frequent, to the point where it would occur when I was idling at stop signs to the point of almost stalling, as well as when in motion. Got harder to bring it back to its senses by pumping the gas pedal. Took it to another garage, they read the code, and changed the 2 spark plug coils.
Click to expand...

Go back to the basics...

If there is a misfire, always inspect the plugs. Here's my reasoning, assume the plugs were cruddy to start with (without being too specific about cruddy), then changing them gave you 3 good weeks until the underlying problem screwed up the new plugs as it had the old ones. Putting on new coils gave the newly crudded spark plugs a bit more oomph and they worked for a while. If the plugs are messed up throw on a new set and you'll have a couple of weeks (probably) to figure out what is messing them up. Worst case, you waste 20 minutes pulling, inspecting, and reinstalling the plugs.

If the plugs are ok, check the compression. Most likely the compression is ok. However, if one cylinder is low the computer will compensate as best it can and that could result in bizarre problems.

Consider basic electrical issues as well, since you are now seeing intermittent problems, and those are very easy to get with any iffy electrical connection. Check the main ground from the battery to the body. If that is corroded anything is possible. Also check the connectors that go onto the coils for corrosion - clean them if they are dirty.

After that, well, there are times when paying a good mechanic is a wise use of time and money.
 
since you're in canada, the EGR valve has an extended warranty... 7 years unlimited mileage... because you got a "CEL", it is pretty easy to get this covered

mention *canadian* TSB # 01-07-17 to your dealer
 
I had this exact problem a while ago, took it into the dealership and they ran several tests. I don't have my service records with me for that servicing (i will have to go grab them this weekend), but i am certain that they did replace the EGR valve. This is in addition to checking the plugs and coils. The car definitely ran smoothly after the servicing, but a few months later i hit the p0300 code again. I asked them if it was possible that the EGR was bad already but they said not likely. So now i am at a loss since i really don't know where to look, and since mazda replaced the EGR valve once it is no longer covered under warranty (if it is in fact bad already).

fortunately this doesn't happen all that often. I read on another thread that this can be related to the fuel pump screen/filter, so i'll take a look at that when the temp warms up in a few months. I also have a few mech buddies who owe me favors, i may call them in and have them look at this with me. I think i could really help narrow down the problem if i was working on it with someone.
 
throwing this out there.

How is your battery? You coils might not be getting enough amps to give the coils power and blah blah blah
 
battery is a brand new optima yellow top, just today mazda gave it a clean bill of health (as a part of their AVR test), full 14.4 volts.
 
Anyone mention timing yet? I had the P0300 for about a year and did everything from egr, coils, plugs, wires, seafoam, fuel pump, fuel system flush, CMP, CPK, etc, etc...

Anyhow it turned up to be miss aligned cam gears (timing related)
 
so what's next?

I also have the engine light on with the OD [over drive] light flashing. Engine light is not flashing - just steady on. Only problem is the OD won't kick in and engine is slightly sluggish, NOT 3 cylinder sluggish.

anyway, This happened after I put in a new battery, but not before I drove and made several stops about 7 miles. On the return trip, that is when the Check Engine light came on steady witht the OD light flashing.
After reading all the parts people replaced, I think it is computer related- not necessarily a bad computer just bad signals. Plus it is below 30 farenheit - makes me wonder if the cold is doing it. But seriously what am I to do, replace the new battery I just put in. I don't have a code yet, but it seems to me if I can make the problem go away by disconnecting the negative or clearing the code, then there isn't really a "real" problem. If the plugs or wires or converter or MAF, or cam timing, or fill in the part.. were bad, it would STAY bad [poor idle, sluggish] whether or not you cleared the code right?
Multiple people saying they got the same code replaced parts and ultimately no change. Something does not seem right here. I am used to working on older cars like 1976 Chevy 350. No computer, if there were a problem with your wires, you couldn't make it go away by "clearing a code", then replace the wires and expect everything to be ok.
Back to my original issue. I got a new battery and after driving it, the check engine light stays on. What might cause that? Both terminals are very tight.
 
trade350 said:
I also have the engine light on with the OD [over drive] light flashing. Engine light is not flashing - just steady on. Only problem is the OD won't kick in and engine is slightly sluggish, NOT 3 cylinder sluggish.

anyway, This happened after I put in a new battery, but not before I drove and made several stops about 7 miles. On the return trip, that is when the Check Engine light came on steady witht the OD light flashing.
After reading all the parts people replaced, I think it is computer related- not necessarily a bad computer just bad signals. Plus it is below 30 farenheit - makes me wonder if the cold is doing it. But seriously what am I to do, replace the new battery I just put in. I don't have a code yet, but it seems to me if I can make the problem go away by disconnecting the negative or clearing the code, then there isn't really a "real" problem. If the plugs or wires or converter or MAF, or cam timing, or fill in the part.. were bad, it would STAY bad [poor idle, sluggish] whether or not you cleared the code right?
Multiple people saying they got the same code replaced parts and ultimately no change. Something does not seem right here. I am used to working on older cars like 1976 Chevy 350. No computer, if there were a problem with your wires, you couldn't make it go away by "clearing a code", then replace the wires and expect everything to be ok.
Back to my original issue. I got a new battery and after driving it, the check engine light stays on. What might cause that? Both terminals are very tight.
Click to expand...

A CEL will never "stay bad" (lit) after you disconnect the battery and cut power to the ECU. Depending on what condition caused the CEL, it might take several miles (or up to 3(i think) trips) for the CEL to come back on.

Get the code read!!
 
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