I have an '01 Protege ES, K&N OEM replacement, and Mobil1 10-30

The engine makes a slight knock on cold start, light pressure on accelerator makes a noise like a little man with a hammer inside my engine.

Dealer says that Mazda is "aware of the noise, but dosent have a fix" ( what is this, software ? ) they have engineering working on the problem, and will contact me when they figure out whats wrong with the car!

Anyone else have funny noises on cold start?

-Mike

 

Other than intakes, that is the most debated issue on this site!!!! Use the search button and you'll find 10-20 threads dedicated to this issue.

 

Normally I'd say the same thing, but the search feature hasn't been working for a few days now.

To answer your question, WhiteBlurs, this is a common problem in 2.0L Protege's. Not everyone has it though, I'd say about half or so from what I've seen. I myself don't have the problem so I didn't pay much attention when everyone here was talking about it, but I remember it has something to do with an emissions control device. There was a temporary fix someone came up with, maybe someone else can post it.

 

the rattle is caused by the variable timing system that reduces cold-start emissions. There is a simple fix, but Mazda can't do it because it disables the Variable timing system. There is a solenoid with a green clip near your sway bar in the engine bay. Disconnect the vacuum tube that is vertical and put electrical tape over it. Then, get a rubber cap from the auto parts store to put on the solenoid. This does no harm to your engine. It simply increases your cold start emissions.

 

I didnt know I had a varible timing system. You're referring to the engine timing being advanced on cold start to get the cat hot faster?

So is this damaging the engine, should I take steps to correct it, as you've suggested I could, or should I not worry about it?

Also, how long do you let the car warm up for before putting it in gear?

 

I wouldn't say the variable timing is damaging to the engine, AFAIK. However, the main reason to "fix" it is because it can be annoying and even a little embarassing (i.e. "look at that ghetto car making all that noise").

As far as warm up goes, I usually only go about 30 seconds in the summer and about 3-5 minutes in the winter.

 

Would you reccomend "fixing" this, do you think the knock is damaging the engine?

Cant be good for it, no?

 

The protege has no such thing as variable timing. THe solenoid you are referring to is the solenoid for the VRIS variable resonance intake system. This is a solenoid that opens up a second set of long intake runners at higher RPMs to let the engine breath better and let the short runners make more torque down low. This has nothing to do with emissions. Whoever told you that is an idoit.

 

So do you know anything of this knock I speak of?

 

The Protege5 2.0L has two solenoids on top of the intake manifold. One is part of the ULEV emissions, I think its called the VTC system (variable tumble control, or something like that), which is meant to stir up the air a bit more so it mixes better with the fuel when the engine is cold. The other solenoid is probably the VRIS system you're refering to. If whiteblurs protege is ULEV compliant, then that rattle is probably the same one I have, and many other have here as well, related to the VTC system.

People on the protegeclub that have taken their car in for the rattle have been told that the cause of rattle is related to timing which is changed to help out with emissions. Somehow, this is apparently what causes the rattling. Some here have speculated that this rattle could be slight knocking or detenation that occurs momentarily at a certain RPM while the engine is cold. I dont know that anyone know for sure what it is. Ive been running with the VTC solenoid vacuum hose disconnected for about 5 months without any problems, other that it seems that the car hesitates if you give it too much gas without warming it up. Once its warm, this doesnt happen any more.

Once the search feature is back up, check it out... there is tons of info on this topic, although its not really a resolved issue yet.

 

WHAT are you talking about follow the vaccuum lines. The one solenoids I explained is the VRIS the other is a solenoid to the Fuel Pressure Regualtor. It cuts off the vaccuum source at WOT to get a full fuel pressure situation in WOT. I have never heard of this VTC you talk of and there are only 2 solenoids one for the VRIS and the other for the pressure regulator follow the vacuum lines and you will see what i'm talking about.

 

Yup, try 5W-50 or 0W-40 oil and that knocking is off. This is a very common issue and doesn't only contain Mazdas. I've had 2 VW's and both had this same property, the knocking itself is not dangerous but if you're worried about it, change better oils.

 

Use search button and get an error message

 

Use search button and get an error message


"There seems to have been a slight problem with the database. bla

 

I thought it the intake control was called VICS. Hmm.