Check engine light 02 mazda p5

[us3r]

The 02 p5 makes a rumbling sound after stopping at a stop light. rough idle. it was doing it twice a week before. today the rumbling sound kept coming at every stop and the check engine light came on. The strange part is that the idle is fine now even with cel on.

The rough idle would usually occur after a cold start. after being driven for about 10- 15 mins the idle would be fine.

I bought this car almost 3 weeks ago. The previous owner replaced pcv, spark plugs, coils, and battery.

 

[zhy]

be sure to have your egr valve cleaned or removed. these are almost alwais the cause of bad idle

 

[tweety2300]

Since you posted this in another thread I'll say the same thing find out what the code is and go from there

 

[P5Zac]

Take off your EGR valve and clean out all the carbon build up, also clean your MAF sensor. Had the same problem a week ago, did those 2 things then went ahead and replaced the spark plugs, wires, and coils. Solved my rough idle problem and fixed the CEL. Had it smogged today and everything is cherry
U can clean the EGR valve yourself and save some money. Do a search on EGR valve and u will find a How-To on it. Same with your MAF sensor...cab be done for less than $15...if u take it to a shop it will be atleast $100...

 

[us3r]

thanks for the responses.

What should I use to clean the EGR valve? carburetor cleaner or seafoam cleaner?

What about the MAF?

thanks

 

[Fresco]

Get the code first, you could also just have a vacuum leak

 

[zhy]

to clean your maf get some CRC Mass Air Flow Sensor/TB Cleaner
using seafoam will not thoroughly clean your EGR, take it out and use brake cleaner on it.
its also a very good idea to seafoam your car, replace sparkplugs,coils,wires
but yeah like fresco said, check your code first, it might just be silly!

http://www.youtube.com/watch?v=vPT8rL0noYg

 

[P5Zac]

to clean your maf get some CRC Mass Air Flow Sensor/TB Cleaner
using seafoam will not thoroughly clean your EGR, take it out and use brake cleaner on it.
its also a very good idea to seafoam your car, replace sparkplugs,coils,wires
but yeah like fresco said, check your code first, it might just be silly!

http://www.youtube.com/watch?v=vPT8rL0noYg

That is exactly what I did, same products and replacements. It did the trick.

 

[us3r]

here are the codes

P0300 - Multiple cylinder misfire (spark plugs)

P0401 - EGR valve low flow

previous owner replaced the spark plugs

 

[njaremka]

dont bother cleaning the egr valve, just replace it.

 

[tweety2300]

If you have p0300 it's probly gona be coil packs not spark plugs

 

[njaremka]

If you have p0300 it's probly gona be coil packs not spark plugs

that code can be caused by the egr valve malfunction. i would change the egr valve before i change the coils.

 

[P5Zac]

that code can be caused by the egr valve malfunction. i would change the egr valve before i change the coils.

Yup, takes a lot longer for the coils to go bad rather than the EGR valve.
You can clean it yourself and it will work for a while but replacing it will take care of the problem for a lot longer. New EGR valves are $130 on ebay, cheapest ive seen them.

 

[us3r]

can i still drive it with damaging any thing else? i will only be driving to school and back. 25 km at most per day until i fix the problem. I will clean the egr valve on friday.

 

[P5Zac]

Should be ok but let it go unsolved for to long.

 

[hotcracker69]

yes dont clean the egr, the problem will come back, just replace it and be worry free for a while. check the intake tube for rips

 

[us3r]

My dad said the egr valve would be hard to remove so he just cleaned the throttle body after removing the battery and intake pipe. The engine misfire seems to be gone. but now the car has trouble starting up after i turn it off. takes about 5 seconds to start up when engine is warm. The idle is all over the place after warm start up. rpm jumps between 500 - 750 and car is vibrating very bad.

not when its a cold start.

the idle is getting worse but the cel is gone. we will remove and clean the egr valve today. I hope it will fix the rough idle.

 

[tweety2300]

Clean iac valve while your at it. Hope and pray you don't have the same problem I did with the not starting when warm

 

[us3r]

The egr hasn't been cleaned yet but the car now runs better. engine has more power and starts up fine. The rough idle is still there but it isn't as bad as before. No cel and it has been 3 days.

 

[us3r]

cel back on...