this is further to my comments on the weekend about the protege rock...that the protege rocks in dense rush hour traffic. i didn't get much support. this is to provide some further comments on the issue, the cause, and the solution. i'd appreciate feedback if my solution is feasible.

to cut to the chase, i think the problem is that the p5 is an ultra-low emissions engine and the idle is so lean that it causes this low speed stumbling, when transitioning from idle to just off-idle. it will be corrected if the p5 computer is remapped to mp3 specs, at least in regard fuel delivery at idle and just off-idle. i don't know anything about engine computers and their adjustability. is it feasible to make this adjustment?

ok now for the details.

1. 1989 accord....the only other time i had a similar rocking in rush hour traffic was with an 89 accord. the service manger told me that it was due to a very lean idle setting in the carb for emissions compliance. he said that honda stopped using carbs altogether the next year because fuel injection could better comply with emissions requirements without these negative driveability side effects.

2. Toronto Star review of the p5, june 9/01..."there's also some driveline shunt/rubber-banding-if you don't get the clutch release and throttle tip-in just right, the car can rock back and forth in dense city traffic. this is an ongoing issue for protege. rubberiness in the engine mounts? too much free play in the constant velocity joints? suffice it to say that this car rewards smoothness, and penalizes clumsiness."

3. Toronto Star review of the mp3, june 16/01...."body roll in cornering is reduced, and rubber-banding--the rocking back and forth protege exhibits when you try to drive the car in slow traffic--seems better too."

4. the p5 is an ultra-low emissions car and the mp5 is not.

when i consider these 4 items together i conclude, right or wrong, that the problem might be corrected by remapping my p5 computer to mp3 specs, at least for low engine speed fuel delivery. are computers adjustable in this way? thanks for your comments.

 

Does this rocking occur when you're just idling, with the car in gear? Are you on the gas at all when it's rocking?

 

any car does this shaky thing when they're at low rpms in first gear as far as I know......

 

Those are interesting comments. My thought has been that the throttle tip in is too fast on the P5, so that engaging and releasing the throttle just off idle results in a big adjustment, causing the rock. The ULEV aspect is interesting to me, and seems to make some sense also.

I guess when people start screwing around with their ecus we should ask them if this condition improves.

Dale.

 

well... I went out and tried to replicate this rocking motion in my new P5.

When I drive it like I always do I do not notice it at all. About the only way that I could get the thing to lurch and bounce around was to (in an empty parking lot at work) release, somewhat slowly, the clutch with the car in first gear and no throttle at all. This caused it to look very much like a jack rabbit hopping along and even caused my co-worker to stop and see if everything was OK.

When apply a little gas and ease of the clutch it runs just fine. I would also say that for creeping along in downtown traffic you really do want to be in 2nd and not 1st.

Good luck.

 

LMAO!!! HAHAHA

 

i find any 4 cylinder car is rocky at low speeds...my parents standard tercel 1.5 liter does the same thing, as some other person sugested just keep it in 2nd gear at stop and go trafic

4 cylinders are ment to rev at high RPM's

 

I am pretty sure that you are going to have a hard time adjusting the current ECU in your car (I have heard of SW to do this, but someone else would need to fill in the blanks). It would seem that you might be able to get an MP3 ECU for your P5? just a thought.

 

When I first bought my P5, I noticed the throttle was a bit more "sensitive" to input than my previous cars. The first few days I drove it I tended to jerk away from lights because I was applying too much throttle. After a few days I adapted my driving style to the car (learned to be more sensitive on the gas pedal) and the problem went away.

What you are experiencing is good throttle response. It's possible your previous cars lacked this, hence the problem your are experiencing now. I wouldn't "detune" the car to fix the problem. Just be more sensitive to your throttle inputs and the problem will go away. And, as others have said, just leave the car in second or slip the clutch in first. Trying to modulate the gas in first gear with the clutch fully engaged can be frustrating in any car.

Oh, just for the record, never rely on the auto reviews in the daily newspaper. The vast majority of these reporters are just that: reporters. Their only interest in or knowledge of cars is that their managing editor assigned them to the job of reviewing cars. They rarely have the experience to be able to tell the difference between a legitimate problem and the "problem" you are currently experiencing.

 

Ok... I'd like to re-open this topic, if I could. (Apparently, the Mods though my "Hello" message should have been moved to this topic anyways )

Has anyone heard anything more on this? Mine does the same thing, and the service dept says it's normal. When in traffic (noticed mostly in 2nd gear) while the car is moving 15 or 20 mph, even if I LIGHTLY step on the gas, the car bucks like I just dumped the clutch. If at that speed, I push in the clutch, and let it out while giving it gas, it's fine. But that's a lot more leg work than should be neccesary in rush hour traffic!

This condition is noticeable in ANY gear under 2000 RPM's but is MUCH less noticeable when at speed. It feels like a very slight stumble at say 45 mph in 5th gear when I am completely off the gas and lightly step back on it to keep my speed.

Has there been any more thought put into using the MP3's fuel curve? Is this something the service department may be able to do? My service advisor and service manager seem to be very knowledgable (read not the "typical idiot" behind the counter). They actually told me it is a very common complaint. They also said I would be able to get a Miata to do the exact same thing.

So is there any new news? Has anyone contacted Mazda corporate to see if there's a case open on it?

Thanks in advance!
Bill "the new guy"

EDIT: for spelling. D'oh!

 

these are my follow-up comments:

-it would take 5 minutes to confirm if the cause is different fuel mapping (or ignition timing) by driving a p5 and mp3 back to back in a parking lot at 2 mph in first gear, regularly taking your foot off and on the gas peddle, without touching the clutch... i predict the p5 will buck and the mp3 will not. unfortunately i don't know anyone with a mp3....(if anyone in toronto with a mp3 could meet me for 5 minutes at a tim hortons, the coffee's on me)

- the comment above that the mp3 has the leaner fuel curve (which would blow the theory) seems counter-intuitive, given that the p5 is the ulta low emissions car

-there have been several comments on one of the other mazda boards recently that the mp3 runs rich at idle, which supports the theory. (apparently the mp3 muffler tip gets black soot, while i haven't noticed this on my p5.)

-i've confirmed that the throttle body and throttle sensor are the same on the p5 and the mp3, so it would seem that, if there's a difference in the 2 cars, it's not in the physical components affecting the throttle tip-in, but the electronic signals coming out of the ECU

-the mp3 ECU costs $1940 in canada, which seems an expensive fix, for only a 10 horsepower gain

-mazda canada basically sluffed me off, saying the rocking is common on many cars

-just to confirm, the bucking has nothing to do with clutch engagement. it happens simply when you take the foot off and on the gas peddle. like dale said above, the throttle tip-in seems too fast when engaging and releasing the gas peddle

- my theory is that mazda knows exactly what they're doing. they know the issue, they know how to fix it. but the ultra low emissions designation is worth the trade-off. based on the responses here, i'd say they made the right call. a few people like me and you find it extremely annoying, but many people don't drive in prolonged stop and go traffic, many are willing to change their driving style to compensate (use the clutch to smooth over the stumble point when accelerating or decelerating), and many will think it's due to their own driving incompetence (when it's not)

-if it was a matter of public safety, i'd ask to the government to order a recall/fix, but it seems more an annoyance than a safety hazard. does anyone know if proteges have an unusually high accident rate in parking lots/slow traffic?

-when i looked under the hood of my canadian p5, the sticker says the car qualifies for california's ULEV status, so we'll share the same problems and solutions in both countries

-my immediate fix was to give the p5 to my wife to drive in suburbia, and i have started driving our hyundai accent in downtown traffic...no bucking at all...my old taurus SHO didn't buck either (**** i miss that car!)

that's it for now. good luck with your inquiries. all comments/suggestions welcome. any mp3's out there want a free coffee?

 

I've driven several P5s and 2 MP3s, and didn't have a problem with bucking unless I induced it. I'm still quite convinced it's an issue with the nut behind the wheel, not one under the hood. It's just a matter of learning to properly modulate the gas pedal. I don't see how a fuel mixture issue would cause this problem.

 

I've driven other cars when people have complained about this very "problem", and was not able to reproduce it without driving the car in a manner that I do not usually drive.

This engine is designed to be driven, not as a tool to get from A to B. The reason the MP3 owners don't complain about this is because they all drive their cars the way it was meant to be driven.

Here are some things that most people don't realize about modern day 4 cyl.

1) Never "cruise" under 2000 rpm. You're killing your engine by doing so.

2) No matter what anyone tells you, it's okay to rev the engine past 4000. It doesn't hurt anything. If it did the rev limiter would at 4k and not at 6500. I actually had a friend who ALWAYS shifted at 3000rpm, no matter how much I tried to convince him that it was bad to do that.

3) It's also okay to cruise over 3000rpm. (In other words, put the car in first during rush hour traffic, if it still bucks, then use the "stop and go" method. It's better then lugging the engine down while "idling along".

Sorry, I'm just tired of seeing posts about this so-called "problem". Yes eventually Mazda will release a "fix" for it, then shortly after everyone will be complaining about the lack of throttle response.

By the way, our car has never bucked unless I made it do it. Even with my very conservative driving Fiancee, of course I taught her out to drive a manual.

Okay, I'm done venting now.
Jason

 

I don't see why most of the people who post to these threads have such an attitude.

I have been driving a standard for 10 years and have owned probably 20 cars that have had a manual transmission in that time, and driven more. This problem has NOTHING to do with the way the car is driven. It is a problem in the computer, most likely in the off-idle fuel mapping. It happens when my wife drives it. It happens when I had a buddy of mine drive it.

My dealer was able to duplicate the EXACT problem in EACH of the brand new Protege's and P5's that they had for sale on their lot. I refused to belive that the problem was normal and swore to him that it was a definate problem in MY car, so we grabbed the keys to about a half dozen cars and he drove, and then let me drive each one. They ALL did it. When EITHER of us was driving. He even took me out in a Miata and it did the SAME thing. He told me it is a very common customer complaint at the dealership, and Mazda has yet to release a fix. So, as you can see, it has NOTHING to do with the way the car is driven. It is built into the car for some reason. All of you who think it's just a driver problem, go out in you car, in a parking lot, and have it idle along in second gear. Now GENTLY step onto the gas pedal. I GUARANTEE it WILL buck. If you keep an open mind and do exactly what I described, it will happen in your car. It has on every Protege' that I have driven.

I don't think you guys are taking the time to understand the problem that is being described. I can intentionally make the car buck while accelerating and decelerating if I drive it like an idiot too. But that's NOT the case here.

At this point, I know it's not me and it is common. I just came here to see if there was a known fix for the problem, NOT to be harassed and told that I do not know how to drive.

And don't get me wrong, I love to drive the car. I go out and stretch it's legs whenever I get the chance. The car only starts to come alive after 4k on the tach! BUT, when the car is used to commute back and forth to work in rush hour traffic, it can't be driven wide open all the time. Do you suggest that I just drive in the breakdown lane or in the grass at WOT to eliminate this small problem??? I can't beleive that it was even suggested not to drive this commuter car in commuter traffic. Unbelievable.

I am quite surprised in some of the attitudes here in this forum. It is noticable in quite a few threads. I am a member of quite a few automotive boards and have yet to run into attitudes such as this anywhere else. Most online communities tend to want to help the members that are seeking help. Not ridicule them for seeking that help. I am very disappointed in the lack of professionalism and maturity in some of these posts.

 

I'm not ridiculing for looking for help. I'm just irritated from seeing this question asked over and over again. I apologize if I came across as ridiculing you.

However, if you ask for help, then you should be receptive to advice given to you. You said two things to bring up. One is that you've been driving a manual for 10 yrs. I would imagine that most of the cars you driven were not 4cylinders tuned the same as these engines are. As you stated it's in the electronics. I wouldn't necessary disagree with you. However, I believe it to be a side effect of the highly sought after throttle response.

The next thing is that you stated, that the problem occurs while "idling in second gear". You really shouldn't do this. The amount of load that you're asking the 4cyl to deal with at this point is incredible. If you're idling along in 2nd gear, then the problem would easily be solved by downshifting to 1st gear, and keeping the rpm's above 2000rpm. If you can't keep it above 2000rpm then use the stop and go method. It's better for the engine, while not necessarily being better for the clutch.

Jason