ph0bolus

I've searched the forums, and couldn't find any threads specific to this issue. I've also had my car ('99 Aristo) at the mechanic to replace some control arms and mentioned it to him, but he overlooked the issue, since it wasn't the reason I initially brought the car to him for.

So, the car runs smooth no vibrations at high speed, or rough idle issues, but every time I'm at a stop light, my car will shudder once or twice each shudder lasting up to a second max. I don't know how to describe the shudder, maybe like when you're relieving yourself or when you're cold. I wouldn't say it's a rough shudder either, just a strong vibration coming from the engine for a second.

I was just wondering if anyone had experienced this, should I be concerned? I had thought it was maybe not enough oil or something, but I've checked it and it's maybe a quarter of an inch past the max. Would that have any play in this problem?

Thanks!

sbagdon

You don't mention which engine.

Are you getting any engine codes?

On a GS4, that shudder can happen when the OCVs are off, and you'll get codes in the P13?? and/or P165? range, usually caused by your engine/cam timing being off, usually a bad timing belt (stretched or mis-timed). Will idle odd, more of a surge then a shudder, and it'll surge when you are steady-throttle cruising (highway).

ph0bolus

Would I get any codes if the check engine light doesn't come on? Yeah, I don't get that surge when cruising at highway speeds only when at a red light. I guess I'll eventually have to take it to a mechanic to check it out. 😩

TrueGS300

I think Aristos only came with a 2jz-ge or -gte. Sound like a motor mount issue to me. If it's running fine. It's common for a vehicle with bad mounts to shudder when coming to a stop. Sometimes they keep vibrating.. Any vibrations too?

ph0bolus

Oh yes, sorry. I've got the 2jz-gte. No, no vibrations at all. Just one or two shudders, three max at the light. They're not in quick succession either, just once after a few seconds at the light then 5-10 seconds later another one.

TrueGS300

Try cleaning your throttle and reset the learned values by disconnecting the battery and holding the two cables together for about 10 seconds. Makes a world of difference in many ways to have a clean throttle.

ph0bolus

Thanks! I'll give the throttle clean a shot, as far as the battery, you mean disconnect both + and - cables, and touch them together for 10 seconds?

TrueGS300

Yes, that clears the computer of all learned values. If you find your throttle built up with carbon around and behind the blade, the computer has adapted for the difference in throttle position to make up for the build up. As it nears the end of it's adjustment parameters it will cause a number of issues with drivability. If you clean the throttle and don't reset it, it will cause a high idle because the throttle will stay open where the computer has learned to keep it and with all the gunk gone it will be like having the throttle open too much at all times.

ph0bolus

Great, thanks!! Gives me something to do this weekend

engin_ear

iTrader: (1)

I also recommend checking for drive belt slippage, and check your motor mounts.

ph0bolus

Thanks I'll YouTube how to do those.

TrueGS300

Be sure to let us know if it makes a difference! Too many threads end with no answer for people searching about the same issue.

ph0bolus

Will do, I checked my garage and didn't have any throttle body cleaner, and was too lazy to go out to buy after work.

I did however check to see if there was any buildup in the throttle, I took some pictures of it...from all the videos I checked on YouTube for research it doesn't look all that bad, but then again I'm no mechanic. There does seem to be some black / burnt marks near the bottom.

TrueGS300

That's a pretty dirty throttle. It will be much worse just behind it. The ring of gunk you see is built up just between the blade and the bore hindering airflow (most noticeable at idle). That and what's behind it will make for poorer throttle response as well. I find it best to remove the throttle body to get a good clean. Use a brush and rags to get all the carbon off and make it shiny like new. You can open the blade, just be gentle and don't force it all the way open or you could damage it.

ph0bolus

I see, watched a couple videos where they had carbon buildup just on the outside so I thought mine wasn't that bad haha. I guess I'll have to look up videos on how to remove it then. I tried opening the blade by moving one of pulley wires or whatever it was that was outside but it didn't move.