Major Protege5 Problems - Please help! Flashing CEL/Misfiring/OBD Non-Op

ericlikescars

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2002 Mazda Protege5
Hey guys. New to the forum, and hoping for a miracle. Definitely going through some buyer remorse.

I just recently purchased a 2002 Mazda Protege5 about two months ago w/ 148k miles.
It is my primary mode of transportation, and a few weeks ago my nightmare started.

Coming to a stop at a red light, the car started to violently studder & shake, and a flashing check engine light came up. Car lost power and I bogged it into the nearest parking lot to await the tow truck.
My buddy has a shop locally, and though he doesn't work on Mazdas and his service is mostly installing aftermarket parts and accessories, he offered me a helping hand due to my financial situation. So I got the car towed there.

He plugged in his reader to read the codes, and claims the OBD port in my car is fried, as neither of his readers register my car. So essentially, I am shooting in the dark with diagnosing this and fixing it. They claimed to order a 17 to 16 pin female OBD2 Diagnostic Connector adaptor cable and give that a try, but the reader still is unable to pull any codes.

Upon inspecting the engine, we discovered a cracked Intake Hose, and pulled off the EGR valve for a cleaning. Taped the hose back up and popped the cleaned EGR in with no real luck (car idled much better for about 45 seconds until the bogging came back and car starts to violently shake) So I'm assuming I'm going to definitely have too replace the EGR to be safe. Next culprit is the plugs and coil packs. I just have a few questions before I go popping a whole bunch of parts into my goody bag.

I've already ordered a new intake hose, and am in the process of ordering a new EGR valve. The only question I have is, there seems to be much cheaper "generic" versions online, for about $90. Whereas the OEM unit seems to run twice the price. As far as EGR valve replacement, should I be definitely going the OEM route? I have read a few times on the forums that there was a "revised" version released, but those are from a few years ago and can't find much too recent as far as what is OK to purchase.

In addition to that, is there a recommendation as far as the spark plugs and coil packs? I guess I'm going to just start with those few items. Intake Hose, EGR Valve, Spark Plugs, and new coils. (Always have ran NGK Plugs in my cars)

Is there anything else you guys recommend? And maybe any constructive advice on whats going on with my OBD? They claimed after going under and looking at the wires near the OBD, it had been "tampered" with.

Sorry if any of my explanations were a little tough to decipher, I'm not too mechanically savvy and doing the best I can here, hopefully I can get some help from this great forum. I really need to get back on the road and transportation for me is a nightmare right now.
 
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Hey guys. New to the forum, and hoping for a miracle. Definitely going through some buyer remorse.

I just recently purchased a 2002 Mazda Protege5 about two months ago w/ 148k miles.
It is my primary mode of transportation, and a few weeks ago my nightmare started.

Coming to a stop at a red light, the car started to violently studder & shake, and a flashing check engine light came up. Car lost power and I bogged it into the nearest parking lot to await the tow truck.
My buddy has a shop locally, and though he doesn't work on Mazdas and his service is mostly installing aftermarket parts and accessories, he offered me a helping hand due to my financial situation. So I got the car towed there.

He plugged in his reader to read the codes, and claims the OBD port in my car is fried, as neither of his readers register my car. So essentially, I am shooting in the dark with diagnosing this and fixing it. They claimed to order a 17 to 16 pin female OBD2 Diagnostic Connector adaptor cable and give that a try, but the reader still is unable to pull any codes.

Upon inspecting the engine, we discovered a cracked Intake Hose, and pulled off the EGR valve for a cleaning. Taped the hose back up and popped the cleaned EGR in with no real luck (car idled much better for about 45 seconds until the bogging came back and car starts to violently shake) So I'm assuming I'm going to definitely have too replace the EGR to be safe. Next culprit is the plugs and coil packs. I just have a few questions before I go popping a whole bunch of parts into my goody bag.

I've already ordered a new intake hose, and am in the process of ordering a new EGR valve. The only question I have is, there seems to be much cheaper "generic" versions online, for about $90. Whereas the OEM unit seems to run twice the price. As far as EGR valve replacement, should I be definitely going the OEM route? I have read a few times on the forums that there was a "revised" version released, but those are from a few years ago and can't find much too recent as far as what is OK to purchase.

In addition to that, is there a recommendation as far as the spark plugs and coil packs? I guess I'm going to just start with those few items. Intake Hose, EGR Valve, Spark Plugs, and new coils. (Always have ran NGK Plugs in my cars)

Is there anything else you guys recommend? And maybe any constructive advice on whats going on with my OBD? They claimed after going under and looking at the wires near the OBD, it had been "tampered" with.

Sorry if any of my explanations were a little tough to decipher, I'm not too mechanically savvy and doing the best I can here, hopefully I can get some help from this great forum. I really need to get back on the road and transportation for me is a nightmare right now.

The EGR isn't active on a cold engine. That's not your issue.

There is a very good chance that there is just a bad coil causing the rough idle/misfire. It's a really common failure. Replace them and look over the plugs and wires at the same time.

Check the ROOM fuse, it powers the DLC connector and can case no communication if blown. The fuses are under the drivers side kick panel, with a diagram in the owners manual.
 
Sounds like exactly what happened when my coil packs went out based on your symptoms of shuddering and the flashing CEL. Changing them with some oem's fixed the problem. I don't know about the OBD reader though.
 
Now may be a good time to upgrade to the 1.8 coil pack found on the older gen protege's and 626. PM me I may have an extra set lying around.
 
So I'm going to start by installing the intake hose as well as the coil pack and new plugs. Someone recommended I change the spark plug wires as well. Just running everything by you guys, finances don't really allow me to just throw money at the thing so I gotta be as calculated as possible.
 
... The only question I have is, there seems to be much cheaper "generic" versions online, for about $90. Whereas the OEM unit seems to run twice the price. As far as EGR valve replacement, should I be definitely going the OEM route? I have read a few times on the forums that there was a "revised" version released, but those are from a few years ago and can't find much too recent as far as what is OK to purchase.
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If you do need a new EGR this is the one you want... It has coolant lines and anyone that has installed it has never had problems with it.

They are a bit of a pain to install but you won't have to deal with your EGR again.

It is only listed for the regular 2002 2 liter Protg at Rockauto but it's the same for our P5. (FS engine...)


 
Coil packs are usually a good start. You can clean the egr and try it because thats free to do before buying a new one. Definetly change the coils plugs and wires. Some guys on here go with duralast because of the warranty. I bought some and they lasted 20k and 1 died giving me the same symptoms you described. I went to oriellys and got import direct brand made by hitachi. Not terribly expensive but a little more than a house brand and it seems ok 50k later. I use the long reach iridiums for plugs and they have never let me down and after 100k still looked good and gap was almost perfect too. But reg copper plugs will get you back on the raod cheaper. Also when my intake cracked I didnt get the cel or rough idling like others have had I just got horrible detonation upon acceleration. If yours is cracked def replace that too its not good for the engine to run unmetered air into it. After plugs coils wires and the intake then see how it runs. If its still throwing a code then try replacing the egr. Of course getting the obd port working is going to help you greatly and Pcb is great with diagrams and electric insights.
 
Not sure if youve purchased the intake tube yet but theres one fs here and hes in the LA area also (boom bump!). The stock one will eventually always crack along the accordian sections requiring inspections periodically where as a cai is more durable. You mentioned finances so not sure if this is a doable option but just throwin it out there
 
Thank you guys for all the input. As far as the intake tube, I have already ordered it was paid for a few days ago. Seems like it is just a generic replacement from CarParts.com

As far as the coil packs and spark plug wires, I was just going to be picking them up from O'reillys. O'reilly also sold me 4 NGK Iridium spark plugs, they were about 7 bucks each. Hopefully these will suffice? I have the plugs already and the intake hose should be here any day now. Just need to know whats recommended for sourcing the coil packs and wires. Should I go to the dealer or will Oreilly suffice? Thanks guys... Bear with me!!!
 
Dealer is best quality coil packs mine lasted over 100k but you will pay a higher price for them. duralast brand were pretty cheap in cost and lasted about 20k for me. I am currently running Import Direct brand coil packs from Oriellys. those are made by Hitachi. At 50k they are going strong. their cost was about half dealer price but double the duralast price if I remember correctly.
 
... Of course getting the obd port working is going to help you greatly and Pcb is great with diagrams and electric insights.

Here's the schematic for the OBD port.
Check for power on the B+ pin.... I'm guessing the pins from options (abs. Cruise) don't need to be active because some cars don't have those options...

 
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Thank you guys! So I made I guess a little bit of productive progress. Though the car hasn't been touched, I'm getting a very good tech out to it on Thursday. Though he agrees on all new plugs, coils, and wires, he just wants to do a compression and leak down test before I go blowing money with no OBD2 codes. Have my fingers crossed, really want my car back.
 
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