Jerking Acceleration And Whinning Noise

[Spookybear 0]

I'm driving a 1999 GF, 136hp, manual.

 

If I cruise along at low revs(e.g. 30km/h in 3rd) and I slam the gas pedal to the floor, I get an acceleration that jerks. Accelerates fine, huge jerk, continues, repeat. Only goes away if I "slowly" press the gas pedal more and more.

 

Video: Jerking happening, 5th gear, low revs (~1100-1200, cruising), followed by gas pedal pressed to the floor. http://youtu.be/pN2VdVhxWPE

 

The jerky acceleration has been an issue for the past few months

 

Recently there's been a whinning noise coming from the "left" side of the engine block(left as in standing in front of the car looking into it). Only seems to start when the engine is warm.

Video: http://youtu.be/xBKjg3deP5M

 

I'm not sure if this noise is related.

 

I was going to post whatever error codes I was getting, but seemingly my bluetooth OBD-II doesn't fit the 626

[djdevon3 827]

I think it's time to pull off the valve cover and inspect the timing components which includes the timing belt, idler pulley, tensioner pulley, and tensioner spring.  All of your symptoms could be explained by poor timing advance (timing belt jumping a tooth).  No idea if the whine is going to be a separate issue or not.  There is a possibility that all of your symptoms are related.  While you're at it I recommend you clean your Mass Air Flow (MAF) sensor and inspect for air leaks.

 

An easy way to pinpoint where the sound is coming from is with a long handled screwdriver (flat head or phillips doesn't matter).  Put your ear onto the long end and use it as a stethoscope just be careful while the car is running not to hurt yourself.  Keep all long articles of clothing and jewelry away from the drive belts.  Put the screw driver on top of the valve cover directly over where the timing belt is.  Then put it on the power steering pump guard above the belt.  Just keep moving it around until you figure out where the sound is coming from.  Once you are able to narrow down where the whine is coming from you'll at least be able to make a more informed choice on what path you should take next. 

 

Whines are usually pulleys or even the accessory belts rubbing on the timing cover.  It's possible you'll have to remove the accesory belts and spin the pulleys by hand to listen for the whine individually and inspect the timing cover for rubbing damage and evidence of fraying on the edges of the belts.

 

Again, the whine may or may not be related there's no way for anyone to tell that based on the information you've provided so far.

[alucard 14]

when was the last time you replaced the fuel filter? that can have adverse affects on the ability to accelerate smoothly...

 

also i should point out that the fs engine was not designed to be run at 1100-1200 revs... it behaves very poorly at anything less than 1500 and will still have a really slow pick up till it hits somewhere in the 2000-2500 range...

 

and whilst i'm on the subject of revs, when was the last time you had the engine revving at anything above 4000?

[XeNoMoRpH 226]

It's not normal at all for the car to jerk, even at 600 rpms. Even though it may not be producing much power/torque, it shouldn't act like it did in your video.

Definitely sounds like some bearing has seen better days. Could be timing components, water pump, or anything else in that area. A stethoscope is really the only way to narrow it down without tearing into it all.

[FADE26 106]

i agree with going through basic maintenance first,..

timing

fuel filter

and air ways,. particularly the MAF

Timing is a bit complicated,. but you essentially check if the necessary markers are set properly,.and if the belt is tight.

fuel filter,.. and all related fuel system components,. including lines. i would suggest fuel injector cleaners,. but that might be just solving part of the problem.

air ways,. check if they are clear. might be a good time to change the filters if you haven't. the MAF sensor should be free from any kind of gunk,. if ever you decide to clean it though,. be very careful,. super sensitive lots of $$$$ if damaged.

also check for any kind of damage around the duct from the MAF sensor to the TB,.. a crack can introduce too much air and mess things up,.that can also produce jerking if ya decide to quickly floor the accelerator,.

the whining,..actually might be related if your problem is timing and/or loose belts,.. have you tried pouring water over those belts? just to see if the sound disappear,..try and wet those bearing areas,. if the sound stops or changes,. you'll know you've hit something.

good luck! let us know if you need anymore help!

and welcome to the forum ^____^ V

[Spookybear 0]

Wow thanks for the fast answers! The whinning noise seems to be coming from my power steering pump. I saw scotty kilmer just uploaded a video on how to fix a noise power steering, seems pretty straightforward.

I checked the car log, it doesn't seem like the fuel filter has ever been changed. Same goes for transmission fluid.

I've also noticed the "power band" doesn't really start before pretty high revs (over 2500), maybe I should start driving in fourth @ 60km/h instead of fifth(the economy still isnt too good though :D)

 

I rev the car to over 4k revs about three or four times a week (I drive 150-250km a week).

 

I'll try the water trick.

 

Also timing belt was replaced at 186k km. I'm not actually sure if the waterpump was replaced too (At 206k km now).

 

I'm going to read my error codes using the 12V LED trick on OBD-1 soon. I'm not actually gonna use a 12V LED, I don't even understand why it's not 5V, I know the car supplies 5V for the radio.

[FADE26 106]

whining at the power steering pump? how is your ATF levels there? it usually do that when its super low on ATF.

considering how the fuel filter was neglected,. is it possible that the power steering too was neglected?

[Spookybear 0]

Alright, so the whinning seems to have stopped, I didn't really do anything.

 

The power steering is def. not the culprit here. No noises coming from it, not now, nor before the whinning went away. I was just bad at locating the noise, but it's not from the pump.

 

I replaced the airfilter and inspected the air intake. No cracks visible. I'll have to use the smoke trick from one of your videos Devon.

 

Belt seems tight.

 

I tried pulling codes, but my damn OBD seems to be an abdomination. It's missing TEN and FEN. 

 

I checked this http://mazda626.net/topic/42924-european-mazda-626-1998-18-no-ten-pin-in-obd-module/

and this http://mazda626.net/topic/41740-my-obd-interface/

 

Doesn't get me anywhere, I'm missing more pins than anyone else it seems. I looked all around the car. I have no connected underneath the dash(at the steering wheel) and nothing elsewhere in the car.

 

However I did manage to pull an ABS code using the TBS. (Also missing FBS....)

Getting this

13 = Right rear wheel speed sensor or rotor

Would that indicate a worn brakepad?

 

Picture of my OBD https://dl.dropboxusercontent.com/u/312127/2014-05-29%2020.32.58.jpg

[djdevon3 827]

Yup that's different.  Sorry but I still haven't quite figured out what the BUS pins are for.  We really need access to a European 626 WSM.  Only year we have is 97 and it's not a good version.

[Spookybear 0]

Yup that's different.  Sorry but I still haven't quite figured out what the BUS pins are for.  We really need access to a European 626 WSM.  Only year we have is 97 and it's not a good version.

http://www.ebay.com/itm/MAZDA-626-GF-1997-2002-WORKSHOP-SERVICE-REPAIR-MANUAL-/300937195851?pt=AU_Clothing_Merchandise_Media&hash=item461141314b&vxp=mtr

would this be sufficient?

[djdevon3 827]

No idea I've never seen one.  Usually they are on a CD and are not actually factory manuals but illegal rips of Mitchell, Haynes, or Chilton Manuals.  I wouldn't buy something like that unless it said something like digital mazda work shop manual.  The US manuals won't do you any good either.  You specifically need a Austrialian version if your from down under or a European version if you're from Europe..

 

Hmm I bet the manual they are selling is the same one on PMX626.info as the 1997 EU WSM.