BamaToy's Garage and Diagnostic Center.

Year: 2010 (122,000 miles)
Make: Toyota
Model: Tacoma / TRD Sport / Automatic / 4x4
Engine size: 4.0L V6

Is a lift installed: Bilstein 5100s with OEM Sport coils @1.75
Aftermarket components: TRD supercharger, TRD CAI, TRD exhaust...that's it I guess.
Is there an alarm system installed: Not to my knowledge.
When did you first notice the problem?: A month ago.
How often does it occur?: Every time I drive.
What have you ALREADY replaced to try and fix it?: Nothing yet.
Have you checked codes?: I checked for codes a while back for a brake light switch issue. I showed that code and a torque converter code. I immediately went to another shop and they only showed the brake light switch code. I resolved that issue and haven't checked since.

I believe I have two distinct issues:

A vibration upon accelerating from stationary. This is a pretty violent vibration, shaking the passenger seat, the hood, the steering wheel, and floorboards. From 0-10mph. Above that, no issues. For example, say the speed limit bumps from 45 up to 55...no vibrations during that acceleration. This vibration disappears when I put it in H4. This all started about a month ago in the middle of a road trip.

My second problem started about a week ago and is a loud clunk when I am slowing down, perhaps at shift points. It seems to happen during braking and coasting in gear alike. It happens in H2 and H4, but if I shift to neutral and coast it doesn't happen.

Let me know what else I need to do to provide you with the information you'll need.

Thanks for your help!

 

Just need a sanity check here. Had a few problems that I posted before. Fixed an exhaust leak and a vacuum leak but still have engine surging and falling at idle. AFR gauge reads a constant fluctuation between ~11-12 to ~16-18.

I believe its the IAC. It will be a while before I get to it and wanted confirmation as well as other potential culprits.

Year: 2001
Make: Tacoma
Model: DBCB 4x4 OR SR5
Engine size: 3.4L 5VZ

Is a lift installed: Yes
Aftermarket components: Turbo kit, IC, 3" exhaust
Is there an alarm system installed: Yes
When did you first notice the problem?: Months ago
How often does it occur?: When idling
What have you ALREADY replaced to try and fix it?: Fixed an intake and exhaust leak that corrected rough idle, running and P1135 code. VERIFIED NO LEAKS AT LOCAL SHOP WITH SMOKE MACHINE.
Have you checked codes?: No engine code or pending codes

 

The second issue with the clunking is most likely axle wrap, which is quite common on a lifted Tacoma. The things to inspect are: Shackle bolts, leaf spring bolts, driveshaft carrier bearing, and universal joints. Check for abnormal movement and/or wear.

The first issue is an interesting one. I am not sure if the first situation with the codes would be related, but it is possible. It would be prudent just to check and see if there are any codes. A serious vibration on acceleration can be cause by many things, from engine misfire, to a loose component, or a bad driveshaft. The fact that it doesn't occur when in 4H may or man not be simply masking the problem. Check all of your suspension bolts and nuts to be sure everything is tight, check for codes in the system, and inspect the driveshaft as well as the carrier bearing. Then get back with me please.

 

You are on a common track of issue with the IAC control system. There have been several failures of the IAC valve that I have seen. You do show a turbo kit installed in your list of aftermarket components. Have you disabled the turbo completely and then checked to see if the condition is still present?

 

Trubo shouldn't have much effect at idle. Ill pull the IAC and clean it out one of these days.

 

I leak in the air supply system could potentially throw a code, or cause an error in airflow. I ran into it several times when I was working on GM diesels.

 

Hello Bama...


the issue I'm having with my truck is that when I'm at a dead stop with my foot on the brake(at a stop light), the truck's idle goes below 500 rpm and starts to shake a bit as if it wants to die. Also, upon take off....when I press the acceleration pedal there is a delayed response.

Year: 2008
Make: Toyota
Model: Tacoma, SR5
Engine size: 4.0L, V6



Is a lift installed: Yes, I have Extended Travel Icon's & Camburg Ball Joint UCA's up front & Dakars in the rear.
Aftermarket components: I have 16" aftermarket wheels with 285/75/16 Muds
Is there an alarm system installed: Factory
When did you first notice the problem?: A couple months ago after I replaced my K&N Airtake with the Stock Setup.
How often does it occur?: All the time now
What have you ALREADY replaced to try and fix it?: No
Have you checked codes?: Yes. The scan tool says "P0505 - Idle Air Control System"

A local TW Member told me I could "pull that sensor and give it a good cleaning. Clear the code and go from there. Or buy a new sensor, reset computer and go there".
I'm not too sure how to clean the IAC or check the sensor....can you advise?

T

 

P0505 is a common code for a dirty IAC system. Current designs for fuel injection systems lead to excessive carbon buildup on the IAC control valve, as well as the throttle plate. A good cleaning of both would be a smart move. It is the lowest cost, and easiest to perform. Use a good throttle plate cleaner and a toothbrush. Using something to hold the throttle fully open, spray a somewhat liberal amount of throttle plate cleaner onto the throttle plate, as well as the bore. Then use a toothbrush to scrub and scrub. After that is done take a shop towel and wipe everything down as well as you can, then do a final spray on the throttle plate. Once you have cleaned it out then start the truck. It most likely will be a little difficult to start at first since there will be some throttle plate cleaner and carbon loose in the intake, but it should clear up reasonably quickly.

 

.... and here's a guide

 

Awesome. Thanks guys! I'll give it a go within the next couple weeks. I have a good feeling that this just might sort out my problem. *crossesfingers*

I'll post my results after I clean everything.

T

 

Oh, Bama.... In this guide-----> https://www.tacomaworld.com/threads/how-to-throttle-body-cleaning-2005-v6.94203/
It's stated to use a flathead screwdriver to open the Butterfly. I was informed that doing this could potentially damage the Throttle Body. Can you advise on this?
I certainly don't want to end up having to replace it as it's like a $900 part from the dealer.

 

Only if you were not careful, would it cause damage to the throttle plates or bore. I would suggest using a small screwdriver's plastic handle to open the throttle plate if you are concerned.

 

Thank you for the advice. I'll probably go that route then

 

I use my finger, and then you can hold it open with the screwdriver or a rag.

 

Year: 2006
Make: Toy-Ota
Model: Tacoma / TRD Sport / Automatic / Pre-runner, SR5, etc..
Engine size: 4.0L V6 (with 136,000 miles)

Bill- I was hoping it was the driveshaft issue on my truck but after the Toyota tech test drive it he said that the Torque converter is on its way out-
$ 5,000-6,000.00 estimate!
Q: is this really how much it will be? are they quoting me right? any suggestions? and why is this happening to my truck!
its only 136,00 miles?!

thanks Bill

 

I have seen converters go out fast, or slow. It can happen. I would get a second dealer's opinion on this, OR I would speak with the service manager and get it in writing that if the torque converter does NOT fix the vibration, that you don't have to pay for it. That is too much money for a "guess" part replacement.

As for the cost itself, Toyota has a TC listed at $900, and the labor time is no more than 5 hours. Even at $120 an hour that is $600 in labor and $900 in parts. I would like to see a copy of the estimate itself to see what they are talking about.

 

Bill thanks for the estimate/quote and the understanding on what the real price is- I'll take note .Well I took my truck in for a full flush at a different dealer a couple of days ago and $260.00 later it 'kinda' quitened down the vibration! I thought it just needed a full cleaning deep inside the transmission. well so far so good...problem solved, you think?

 

I would ask the adviser if your year model has any transmission or ECU updates, bulletins, or recalls. I do not recall if this model has just a filter screen, or an actual filter on it.

 

Year: 07
Make: Toyota
Model: DCLB Sport 4WD
Engine size: 4.0 V6
Is a lift installed: no
Aftermarket components: aftermarket rear leaf springs is all
Is there an alarm system installed: yes viper
When did you first notice the problem?: a couple months ago
How often does it occur?: so the best way to describe it is a front end shutter. It happens from complete stops to about 6 mph every time I start with the steering wheel turned. If it's straight there are no problems. It goes away once I accelerate and only seems to be an issue from full stop.
What have you ALREADY replaced to try and fix it?:
Not for this reason but the tires were just replaced and balanced. Other than that nothing.

 

I would search for and read the thread on ECGS front diff bearing. Compare what you find there to what your condition is. Get back with me if you feel that the issue is not like yours.