Surging cruise control

[super_vixen]

I've noticed this issue with my car for the past...year I'd guess. I don't use the cruise that often, but now that I'm doing a lot of driving on the 407, it's become a daily occurance.

It feels like my car is surging when I put the cruise on, regardless of whether it's flat or a hill. And it's not a strong surge, its like...an repetitive surge that I can feel because as a driver, you can feel these things.

I know my car didn't do this when I first purchased it, but due to the small amount I used to use it, I can't determine when this started happening.


Anyone ever experienced this or have any idea what might be happening? I'm scared to take it into the dealer again, because we all know my luck *rolls eyes*

[dsichewski]

I've had that happen to me every now and then...mine has normally happened on the 401 and it will be normally a straight away...usually what happens that i've noticed is say i'll be doing 100kmh and then traffic slows so i turn cruise off and i hit the cruise back on at 90kmh but then i feel the car surge ahead like its trying to regain the 100kmh mark....normally i'm sitting behind someone so it kinda catches me off guard...I just hit the brake right away or hit the cancel button and it slows the car down and then i put cruise back on and its fine....Never really thought much of it just figured it was more of since the off and on selections were close together it didin't pick up the speed differance.....

[super_vixen]

Yeah - that doesn't quite sound like what mind is doing. Mine is a consistent surging from the second I turn my cruise on. It feels like you're bobbing your head front the back because its so rhythmic.

[3GFX]

Is it me or are we all up a little late? At least I'm doing homework :p

Vixen, I think its just regular to me. Cruise control on many cars isn't very smooth in its integration. Our cars are a good example, hit the accelerate button and she'll wanna kick down a gear into 3rd which really pushes the head back.

A trick I use is to keep it in the 'manumatic' mode while in cruise control and keep it in 4th (or 5th if you have th 5spd auto) so that it works a little more smoothly.

I don't know if that will be the answer to your CC problem, but maybe it will help.

If that won't help what speed are you cruising at? Is there any other issues that might be causing this? Everything else feel normal?

[Skarbro]

That isn't normal. Cruise should be smooth. I'm guessing the cruise control module needs replacing.

[3GFX]

Yea, it depends. But I guess skarbro's right. It should generally be smooth, cruise control can never substitute for a smooth pedal ;)

[Jeff-TheBiz]

Is it actual switching abck and forth between 2 gears when the surging happens or is more of the feel of the gas being pressed abruptly?

[Flagrum_3]

Probably just needs the program reflashed :)


_3


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[super_vixen]

3GFX - I was doing homework too :) Nothing like homework after 1am :)
As for speed, I usually turn it on when I'm up above 110km/h on the highway, provided there are no cars around and it's just going to be smooth sailing into Toronto.

Biz - it's not switching gears, and its not even an abrupt feeling, but I can definitely feel a funny back and forth motion in the car (its probably not even that noticeable to any passengers, but as a driver, I can feel it more)

Will a reflash help that? and if so, how much does Mazda stick for that?

[Flagrum_3]

Will a reflash help that? and if so, how much does Mazda stick for that?

Well if your not noticing any surging during regular driving, and it occurs only with the cruise on...What else could it be? Well I guess it could be the cruise module, but I like to think of the least possible fix and if your car is still under warranty I don't know if they would charge you or not for a reflash, I guess you'd have to call them and find out.


_3


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[Skarbro]

Reflashing is really a stretch. I have never heard of reflashing needed for solving a cruise control problem.

This is what you need to do: Diagnose the cruise control switch first. This is what any tech would do first. I willing to bet the problem lies here. The fix is to replace the cruise control switch. I do believe they are not that expensive. Flippy can give you a price.

http://img139.imageshack.us/img139/408/cruise1my1.jpg
http://img139.imageshack.us/img139/4097/cruise2rf7.jpg

[Flagrum_3]

Reflashing is really a stretch. I have never heard of reflashing needed for solving a cruise control problem.

This is what you need to do: Diagnose the cruise control switch first. This is what any tech would do first. I willing to bet the problem lies here. The fix is to replace the cruise control switch. I do believe they are not that expensive. Flippy can give you a price.

http://img139.imageshack.us/img139/408/cruise1my1.jpg
http://img139.imageshack.us/img139/4097/cruise2rf7.jpg

I beg to differ, in that the procedure you are showing would undoubtably be done, if the Cruise is not working at all.And maybe the part would be low cost but the labour would not.

And this is not the case here, has her crusie is working, she is only experiencing surging.Think about it; What would cause surging on cruise? There is numerous answers, but I just mentioned the least intrusive fix....I would be tempted to just try the ol' battery disconnect for twenty minutes, just to see what happens.


_3


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[Skarbro]

Ok I'm being swayed now. Apparently you can request PCM flash upgrades when you bring the car in. If it doesn't cost anything, then why not.

I still think though that it is still possible for the switch to cause the problem. If the switch is shorting, it could be sending signals to the PCM (like stop/go/stop/go).

[Triznox]

Any luck with this. I am having the same problem.

[Jazzy]

I'm also having the same problem. Does anyone know if the switch could be the cause?

[Triznox]

I doubt it is the switch. The switch should either work or not. The on/off surging feeling we have has to be something else. Trans mission wouldn't matter either. It seems to hold close to the proper set speed, it just seems to goose it, then let off every couple seconds. I came across a TSB for cruise surging but it was for a 2.0L engine. A firmware upgrade was the solution there. I hope it is the same deal for the 2.3L as that is what I have. Any body else see this on the 2.3L?

[froggy]

don't use cruise control anyway you're driving the car not the other way around. I know it's there as a convenience but I personally like to be involved in as much of the experience as possible, ie manual transmission and no cruise just my 2 cents. As for the problem with the surging does it do it at any other speed range? slower or faster?

[Noisy Crow]

Agree on it not being the switch. The switch isn't even an on-off thing... it just signals the PCU what to do, as do the speed up/down buttons. And once it's toggled to off toggling back on would still leave the speed unset. If was the speed up or speed down buttons the speed would consistently drift in that direction.

Three possiblities come to mind:
1. Need an to update the PCU programming, as noted above
2. Sticking throttle actuator
3. Flaky vehicle speed sensor


For (1): Check the TSBs
For (2): Assuming drive by wire (not sure of the year/region change between cable linkage and drive by wire) pay attention to the car's reaction as you drive on a slightly hilly road while you try to keep the same speed
For (3): Not much you can check yourself...

[TheMAN]

well if any of you recent repliers have searched, you would've found a post I made a while ago about ABS sensors could be possibly causing the issue

there was a car that came in years ago with a cruise surge... it was very bad.... it also was a 2.3, so no ECU flash fixed it.... a throttle body was replaced and the accelerator cable inspected... the speedo sensor signal was inspected and all wiring under the hood inspected.... finally the ABS speed sensor reading was looked at and the speeds came back fine, but when the signal was inspected under the oscilloscope, one of the sensors had a "dirty" signal... it wasn't a smooth line at all, but there very minute "jaggies" variation in the signal that DID NOT cause the ABS light or CEL to come on... ABS wiring was inspected and it was found one of the sensor wires rubbed through by a wheel because some retard who worked on that car before left out one of the wiring brackets... obviously the bracket couldn't be covered under warrantied, so the new sensor wiring was just zip tied out of the way and the car went on its way under warranty

[Jeff0]

So is this normal when you had set the cruise let say 110Km/hr and OFF it, then my speed drops to 70km/hr then turn back ON the cruise, the car changes gear and speed up abruptly to the set speed. But sometimes when I tried this it will just smoothly increased its speed until the set speed, I don't know which is normal in this two scenario.

[Malcolm991]

Mine surges all the time to maintain speed on hills, etc! I would be worried if the car didn't stop picking up speed!

[Triznox]

well if any of you recent repliers have searched, you would've found a post I made a while ago about ABS sensors could be possibly causing the issue

there was a car that came in years ago with a cruise surge... it was very bad.... it also was a 2.3, so no ECU flash fixed it.... a throttle body was replaced and the accelerator cable inspected... the speedo sensor signal was inspected and all wiring under the hood inspected.... finally the ABS speed sensor reading was looked at and the speeds came back fine, but when the signal was inspected under the oscilloscope, one of the sensors had a "dirty" signal... it wasn't a smooth line at all, but there very minute "jaggies" variation in the signal that DID NOT cause the ABS light or CEL to come on... ABS wiring was inspected and it was found one of the sensor wires rubbed through by a wheel because some retard who worked on that car before left out one of the wiring brackets... obviously the bracket couldn't be covered under warrantied, so the new sensor wiring was just zip tied out of the way and the car went on its way under warranty

After thinking about all the various things mentioned in my searches, this sounds like it maybe my problem. I recently had both front bearings replaced. Before that I took a long road trip and used the cruise control lots without any problems. Didn't leave the city for a month or two when I took the car in to get new bearings. Few weeks later went on the highway and noticed the cruise surge. Since the abs sensors are down there, maybe I have a missing bracket, bad wire, or damaged/improperly installed sensor.
I'm interested in what you saw here. I know nothing about oscilloscopes, but know people who would. What is the procedure you used? I'll look for worn wires and anything else in the wheel wells, but how did you use the scope to know there was a problem?

[Spork]

I recently had a similar surging issue after my front wheel bearings were replace with NAPA authorized hub assy (Part Number: ATM 2121315).

Upon setting the cruise control, the Engine RPM and speed remained the same; however, I could feel the acceleration and deceleration within the same second. Sensors and the same napa hub assy were replaced, but issue still existed.

At the end my mechanic replaced the aftermarket bearings with the mazda 3 OEM bearings. Issue was fixed.

This happens because there were magnets in the bearings that sent signals to the ABS sensors. And perhaps the aftermarket bearings aren't up to the spec. My mechanic showed me the aftermarket signal lines weren't entirely a straight line.

Lesson Learned: Use Mazda OEM bearings.

[Danno]

I have the same issue with my 2005 Sport. It almost feels like the drive train is elastic. I also have another problem showing up at cruise, The car will slow a bit and you can hear continuous spark knocking. If cruise is active, the gas pedal will go nearly to the floor to maintain the speed, occasionally downshifting. Then...it is all Ok again. The dealer ran the codes, no failures, none pending. Any thoughts? The car has 192,000 Kms on it and still runs well but for this.

[Booter22]

I have the same issue with my 2005 Sport. It almost feels like the drive train is elastic. I also have another problem showing up at cruise, The car will slow a bit and you can hear continuous spark knocking. If cruise is active, the gas pedal will go nearly to the floor to maintain the speed, occasionally downshifting. Then...it is all Ok again. The dealer ran the codes, no failures, none pending. Any thoughts? The car has 192,000 Kms on it and still runs well but for this.

There was a tsb for cruise, ask them if this could be replated.
TSB 01-06-14
2004-2005 MAZDA3- 2.0L MT-SURGING FELT WITH CRUISE SET ONLY
BULLETIN NOTE

This bulletin supersedes the previous bulletin 01-06-07,issued on 04/06. The WARRANTY INFORMATION has been revised.

APPLICABLE MODEL(S)/VINS

2004-2005 Mazda3 - 2.0L (LF) engine w/Manual Transmission (MT), Federal & Canadian Spec vehicles only

DESCRIPTION

Some customers may complain a light surging may be felt when cruise control is set and the vehicle is cresting a hill or going downhill. The speedometer stays constant, and the light surge is felt when the throttle adjusts to maintain a constant speed.

The cause is throttle valve versus fuel-cut system strategy depending on inclination of the slope in order to maintain vehicle speed. The PCM logic has been changed to fix the concern starting Job #1 of 2006MY.

does that sound like it?

for the tsb it looks like it needs a pcm update, clean the keep alive memory, and road test to confirm.

[Danno]

Hi John. I am from the Chatham area and it is as flat as a lake bed down here. I will inquire about the cruise TSB next time the car is in to the dealer. I am more concerned about the other problem with the spark knocking. This also seems to occur only when the car is warmed up. It feels as if the brake is being applied, but the spark knock is happening on all cylinders by the sound of it. Then it goes away. It would be great if it would just quit, then I could get it fixed.

[Booter22]

Hi John. I am from the Chatham area and it is as flat as a lake bed down here. I will inquire about the cruise TSB next time the car is in to the dealer. I am more concerned about the other problem with the spark knocking. This also seems to occur only when the car is warmed up. It feels as if the brake is being applied, but the spark knock is happening on all cylinders by the sound of it. Then it goes away. It would be great if it would just quit, then I could get it fixed.

i looked for tsbs on that as well the only one i could find was for b series but they all pretty much said to update the pcm, otherwise it could be faulty plugs, coils so on..