Jump to content
LegacyGT.com

Cruise control oscillating


Recommended Posts

I've been doing some maintenance and following it my cruise control is now oscillating. Meaning there are subtle surges of acceleration that sort of pulsate the car along. Just enough to be annoying. I don't know how the cruise control is controlled, so I'll list the maintenance that has been done recently:

 

Transmission fluid drained and filled

Transmission fluid filter changed (Battery removed)

Spark plugs changed

Right axle boot changed (Axle removed)

Left axel and hub replaced

 

Before all that it worked fine and was smooth.

 

So is there any mechanical control in the engine that may have been bumped or broken? Or did the disconnection of the battery cause the tune to get lost and the computer to go 'wonky'? The car doesn't seem to be running any different, and this issue is only felt while under cruise control.

 

Any help/information would be greatly appreciated! I commute 80 miles a day and a lot of that is on the freeway under cruise control. So having it oscillate like this may drive me insane!!

Link to comment
Share on other sites

Interesting. The reason I had to replace the bearing and axle is because they were seized to each other, and the knuckle was really rusty. That whole area was rusty. I had to use a lot of torch heat to get the axle out and then the hub out and the busted lower ball joint out of the knuckle.

 

I'm guessing the "fix" is to pull all that apart again and clean the hell out of the knuckle?

Link to comment
Share on other sites

^ Some have had good results with that, others no. If it was really that rusty then maybe so, if you had to tap the bearing in at all that's not good, and I 'd recommend taking it apart and re-cleaning. What brand of bearing was installed?
Link to comment
Share on other sites

I put in a MOOG bearing. I didn't tap it, per say. I used the bolts to pull it in, but it wasn't the smoothest. I am planning on putting it on a rack Saturday and cleaning it up. I really hope that works because I'm going insane on my commute.

 

To clean up the knuckle, sand paper? Brake cleaner? Anything else?

 

Also, maybe I should pull the ABS sensor out again to clean it? Anything else I should pay attention to with it out?

Link to comment
Share on other sites

Yea if you had to use the bolts to pull it in I doubt its straight. Sure pull the sensor and clean the mating surface. To clean the knuckle I'd go with something heavier then sandpaper, can you get a wire wheel on a drill or something, you really want no imperfections and the bearing should just set in and be ready to tighten it down. Hope it goes well, please post results.
Link to comment
Share on other sites

I may have been incorrect in using the bolts to pull in the hub. Regardless, I tapped the hub out and it came out pretty easy. I also took out the ABD sensor again and cleaned it. I took a wire brush and cleaned out the seat as best I could. But there is still corrosion in there. However, the hub slipped back in fine. I cleaned it all out with parts cleaner than made sure to tighten down the bolts evenly in a cross pattern. Unfortunately it all didn't help. I've still got the same oscillating issue with the cruise control.

 

Any other ideas that may be causing this issue?

Link to comment
Share on other sites

I may have been incorrect in using the bolts to pull in the hub. Regardless, I tapped the hub out and it came out pretty easy. I also took out the ABD sensor again and cleaned it. I took a wire brush and cleaned out the seat as best I could. But there is still corrosion in there. However, the hub slipped back in fine. I cleaned it all out with parts cleaner than made sure to tighten down the bolts evenly in a cross pattern. Unfortunately it all didn't help. I've still got the same oscillating issue with the cruise control.

 

Any other ideas that may be causing this issue?

 

I almost guarantee that the aftermarket hub unit is the problem. I just went thru the same process you did and the solution was that I installed OEM hub units.

 

I don't know if the magnetic rings are weaker or a different pulse count on the aftermarket units, but this a well documented problem.

 

http://legacygt.com/forums/showthread.php/success-non-oem-wheel-hub-bearing-units-221269.html

 

I connected my Cobb unit and it showed the throttle plate was fluctuating about 3 %, not enough to vary the speed but you could feel it in the seat. The previously mentioned post shows that some success has been had using Detroit Axle hub units.

Link to comment
Share on other sites

Interesting. The reason I had to replace the bearing and axle is because they were seized to each other, and the knuckle was really rusty. That whole area was rusty. I had to use a lot of torch heat to get the axle out and then the hub out and the busted lower ball joint out of the knuckle.

 

I'm guessing the "fix" is to pull all that apart again and clean the hell out of the knuckle?

 

You may have damaged your wheel speed sensor as well. Usually cleaning the hell out of the knuckle to bearing surface is an exceptionally good idea.

Link to comment
Share on other sites

If you didn't clean the hub before putting the bearing in, you will have issues.

 

Most just bite the bullet and buy the OEM Subaru front wheel bearing.

 

The rear has no real issue tied to brand names.

 

Moog has stood behind their product before on this issue, so I would venture to say the error is in your installation. The new hub should slide right in.

Link to comment
Share on other sites

I had this happen in september. I got a duralast and the cruise would pulse then shut off and the cruise would flash. Returned the duralast and bought the Timken. Problem was solved. Only the cheaper bearings can be used on the rear, but this was the first and last time I don't get a timken
Link to comment
Share on other sites

Was that 300 for the parts and labor or just the hub ?

 

If parts and labor, that's not that bad. I think the hub from Fredbeans is like $140. Check Heuberger too, both are Vendors here, click on the link up top.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

http://legacygt.com/forums/showthread.php/new-short-block-time-215312p14.html

 

read post #547 and 548. Also a few post earlier I posted more links.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.



×
×
  • Create New...

Important Information

Terms of Use