Check Engine Light, P0303, VICS-VTCS valve actuator

[trea's 5]

Would like some help. I not a mechanic, or a millionaire, but am teachable. I apologize about this being so lengthy but here it goes...
2002 Protege5 automatic no mods
145,000 miles


A few weeks ago CEL came on: P0303 / P0660 / P1659
Replaced plugs and boots (which were less than 2 years old and looked fine).
Plug wires are less than 2 years old and good ohm reading (checked the same new set at parts shop to compare)
Coils ohm showed good.
Checked for vaccuum leaks.

Days later the CEL came on: P0303
Cleaned MAF sensor
Cleaned throttle body.
Checked again for vacuum leaks
Swapped coils around (to see of misfire cylinder changes).

Days later the CEL came on: P0303 (I guess that probably rules out the coil since I swapped them). Did the following:
VICS valve actuator (rod) was not moving so I swapped soleniods, with VTCS soleniod. Bad soleniod, a $100 fix (ouch!)
Checked all the hoses (again) for vacuum leak(s).
Checked and spray cleaned the electrical connections (yea I'm deperate).
Removed and cleaned the EGR, replaced the EGR gasket.

Went highway driving and CEL came on at 50 miles. I was accelerating, from a slow speed, to get onto the freeway. Car felt like it was struggling and the CEL came on -flashing- and the ride was struggling (doing 45 mph by now). I pulled over, shut her down, waited a minute, then started it up. Had a solid CEL. Drove 50 miles back home. (It happened at night so no AZ open to read code).

Here are the Symptoms:
While car is idling (any gear) will be around 700-800 rpms and will drop 50-100 rpms for a split second, like a bump. It is random (maybe once in 15-30 seconds or it could happen four times in 5 seconds, no specific pattern. It is doing it more frequently than when it started a few weeks ago. I don't notice it when driving at higher speeds/rpm, if it is happening it is very subtle.
________________________________________

Issue 2 (could this be a cause of the CEL)

While addressing the VICS solenoid issue I noticed the VICS and VTCS valve actuators (the gold disc/dome looking parts with a rod extending from them)look the same. When I was manually checking them -
VICS actuator moves easily (both directions - the spring moves the rod to go back immediately.
VTCS actuator is harder to move and when you release pressure, the spring moves slowly (I can move my hand faster than it goes back)

Dealership says they don't sell the parts separately, I would have to buy the unit they are attached to (shy of $600). Parts guy is going to call mazda tech and see if:
1. Are they the same part
2. Do they sell them individually

Was wondering if anyone here knows if they are the same part and how is there a DIY way to check them..

I will be coming back with questions/suggestions on my CEL issue after my trip to get the code read (again).

 

[trea's 5]

Follow up on the VTCS moving slower. I took off the VTCS delay valve and realized this is what is "slowing" the VTCS actuator from moving as fast as the VICS actuator. Blowing air through the delay valve was hardly noticable (have to blow hard). When I used a little air from compressor it is defininately noticable. Please excuse my ignorance, I am learning as I go. Have pulled up manual and don't have all computer / gadget stuff but am trying to make some sense of it all. Kind of hard to follow the flow chart when you dont have tools/computer hook ups etc.

Still open for suggestions...

 

[trea's 5]

Update

AZ just read CEL code: P0303

Don't know if this sympton helps troubleshoot...
While I was idling (in drive) I turned on the AC full blast. When I accelerated it was struggling to get up and go. Did this a few times with/and without AC to see if it would duplicate. AC on makes it bog/hesitate/struggle when I am accelerating from a stop. Once about 2.5k - 3k rpms it rolls along fine.

(Ever feel like you were talking to yourself?)

Any help is appreciated.

 

[Jedidiah55]

Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Running out of fuel
Poor compression
Defective computer

maybe a bad wire

 

[trea's 5]

When you say bad wire, I take it you mean could be one of the many running through the main harness and to connectors? I will look again, harder than before. Thanks

 

[sunkAlias]

p0303 means that your 3rd cylinder is misfiring.

 

[sunkAlias]

Sorry, maybe you already knew that but it just sounded like you didn't by the way you're troubleshooting. I had a 626 before my protege that was misfiring and swapping in a new wireset fixed the problem. But, I don't really know what to do since our protege's don't just have a simple distributor with 4 wires.

 

[Jedidiah55]

loose connector

 

[trea's 5]

Here's a video of what the car is doing.


[video]http://www.youtube.com/user/Criv388?feature=mhee[/video]

 

[sunkAlias]

Bro I def think one of your cylinders is misfiring. Change the wires to cylinder 3 and see what happens. But do something soon because the misfiring will ruin your cats costing even more money!

 

[CheeseHelmet]

Thank you for your write-up, very rarely are we presented with so much detail

I have a similar problem (as seen in your video) except it happens maybe once a month for me. At a stoplight the engine will stumble once, recover, and then run fine. I've just ignored the issue because it happens so infrequently.

I think we should focus on the P0303 DTC since it seems to be the only reoccurring problem. The service manual says that it's a misfire in cylinder 3 with the following possible causes:

1. Spark plug malfunction
2. High-tension lead malfunction
3. Fuel injector malfunction
4. Air suction in intake-air system (between dynamic chamber and cylinder head)
5. Inadequate engine compression due to engine internal malfunction
6. Related connector or terminal malfunction
7. Related wiring harness malfunction

I think we can eliminate 4 just because the chance of it happening seems slim. Also, we can get rid of 6 and 7 because if there was a problem with the wire harness or connector you'd see a problem with the adjacent cylinder (#2). This is because our cars use a wasted-spark ignition scheme, so if one coilpack fails you end up losing two cylinders. For now we'll assume your coilpacks are still good because of the test where you swapped them and nothing changed.

I'd recommend checking items 1, and 3 the same way you did your coilpacks. Swap the plug or injector with one from another cylinder and see what happens. Be careful to match the fuel injector color when doing the swap (green for green, purple for purple), also you might want to pick up new o-rings for the injectors as they tend to get damaged during removal/installation.

I left #5 on the list because it's possible that your engine ate a loose screw from one of your intake manifold butterflies (search for "ViCS recall"). You can get a compression tester from harbor freight for pretty cheap to rule that out.

Finally we come back to the spark plug wires. Your test was not adequate to determine if the wire is good or not. An Ohm meter does not replicate the conditions that the wire is normally subject to (very high voltage at a moderate frequency). If there is any compromise in the insulation of the wire or boot (you might not even be able to see it!) it could be shorting to the block. Have you noticed the problem gets worse in humid/rainy weather?

 

[trea's 5]

Thanks for all the input. The car has been sitting except for AZ run for DTC and the video. I am about to run through the items mentioned above. Will let you know soon...

 

[trea's 5]

Well I changed the wire set and gave it two days of driving... no CEL or symtoms. (I still have my receipt on the old wireset - still under warranty - so I will be getting reimbursed for the new purchase) The 5 seems to be well again. I knew my chances of getting reliable help was here on the forum. It's kinda cool that "long distance" help, from people you've never met, is possible. Thanks again one and all. If I run across anything that may help I will pass it on.

P.S. Here is $20 Mail-in rebate on synthetic. I could not find this rebate form on the company site but was able to get it another route. Wal-m sells it. don't know where I'd post info like this so it can be passed on.

http://www.getg.com/campaigns/request.php?cID=getg111012