When i'm driving on the highway, and holding my gas pedal steady. The car will studder a little bit, almost like i'm taking my foot off the pedal. It's a quick shudder, or loss of power. The weird thing is that it doesn't happen when cruise control is enabled. Therefore i wouldn't think it could be a fouling spark plug. Do you think it could be something wrong with my Drive By Wire system?

Any ideas?

Thanks-

Damon

 

Are you getting any sort of Check Engine Light such as one flashing? Does this also happen during prolonged city driving? Are you using premium fuel?

If you are using premium, have no CEL and aren't sure on when it happens, it could be a problem with the Accelerator Pedal Position Sensor.

 

I think csmeance is right, sounds like a throttle position sensor. Since the cruise control works independently of the accelerator pedal and the tp sensor, it could easily explain why you have no problem while using CC.)

There was a thread on this recently...(try doing a search.)

 

yep. that's exactly the problem. you guys just saved me about $300. the mechanic's quoted me 450, before i posted this on AZ.

thanks again.

 

I have the exact same problem with my 2005 TSX (AT). I changed out the APP and the problem did not go away.

 

then, you DO NOT have the same exact problem.

Please, list your symptoms.

 

Intermittent shuddering (that's the best way to describe it) while maintaining speed. Does not happen with cruise on. Eliminated plugs and coil packs, accelerator position sensor and possibility of water in fuel. There is no EGR on my car as far as I can tell or I would have suspected that too. I am currently thinking it may be caused by the CV joints or the intermediate driveshaft that is located on the passenger side.

 

The last time I had an intermittent shuddering was caused by faulty O2 sensor, in my case Check Engine Light came on with P1157 code.

 

Intermittent shuddering points to a few things:
1. Check injectors and clean
2. Check fuel pressure & fuel filter
3. TSX has EGR, you should clean that out
4. I suspect it's the transmission, do a fluid change on it. Every 30K with Acura DW1 Fluid for AT is what I recommend.
5. How many miles on the car?

 

I have about 185,000 km (115,000 miles) on the car. Thanks for the advice. I will work my way down that list. Where is the EGR valve located?

 

Just wanted to let you all know that my shuddering (my Acura service manager called it "juddering") problem is GONE! I changed the ATF 3X and that did it.

 

Oh yeah, if you have no rough idle or other gas or O2 issue, I would say it is the Pedal Sensor. I lived with a no-CEL hesitation in the pedal for 30,000 miles and took it to the dealership 4 times with no resolution. They claimed I didn't know how to drive a stick because they couldn't duplicate the problem.

Well, it finally "coded" and my car felt like an old Chevy with pitted points when I pressed the gas. I had an "Emissions" and "ESC" light, and I couldn't go in cruise control any longer. Replaced the APP, and I finally have the relief of being able to sit in traffic without hiccuping down the road and looking like I don't know how to drive a stick. Smooth as silk, like it was 35,000 miles ago (105,000 now).