BamaToy's Garage and Diagnostic Center.

I'm not so sure I agree with this.

I've spliced speed sensor wires twice. Once on a Tacoma and once on a Tundra. Both times the speed sensor issue was solved by reconnecting the wires. Just be careful to use quality wire solder and adhesive lined heat shrink tube.

At $100 plus for a wheel speed sensor, I figure a quality solder job is money ahead.

I think we can all agree that the wheel speed sensor wiring is a weak link on our trucks.

 

NOT DO DISAGREE WITH BAMATOY... I am sure he is right that they are sensitive wires, but they are not shielded. I spliced mine but i am an electrician by trade (submarines). I would not use a butt splice. If you want to save money try finding a wrecked truck and pull them off of it. Unless ABS failure caused the wreck

 

Thanks! I will be getting the wife in the drivers seat while I lay underneath the truck. I like to live dangerously...

 

I was not trying to say that anyone is patently wrong in splicing speed sensor wires. However if you look up manufacturer recommendations they will agree with me on this. Yes, you can solder the connection and it may hold solid, however the sensor wires for a speed sensor are twisted together and shielded for a reason, and that is to keep out EMI which can cause not only erratic ABS operation, but unwanted accidental application of the ABS system. A perfect example is the late 90s and early 2000 model Cadillac Deville/Seville/ElDorado vehicles. Even with a shielded pair of ABS wiring, the factory routing of the left front sensor was too close to the windshield wiper motor. This resulted in application of the ABS system when on wet roads due to EMI induced into the ABS wires from the wiper motor operation.

When it comes to a person's personal safety, I am not one to take a chance. Nor will I ever make a recommendation for a repair that could even have the slightest risk of causing someone to have an accident and/or get injured. There is a nice big fence to stand on between fixing something and fixing it right. I won't make a recommendation to anyone that I feel is not safe, and the correct process.

 

Not a Toyota but need so insight

Year: 1999
Make: Honda
Model: Accord LX
Engine size: 2.3L I-4
Transmission: 5-speed Manual

Aftermarket components: All stock
Is there an alarm system installed: No
When did you first notice the problem?: Upon purchase *178k miles
How often does it occur?: Regularly
What have you ALREADY replaced to try and fix it?: No
Have you checked codes?: Cat converter efficiency code for bad down stream O2 sensor which is seized and stripped.

Problem description: When releasing clutch in 1st gear, reverse and sometimes 2nd gear, I get a clatter noise but the clutch hooks up and doesn't slip. I figured my throw-out bearing was going bad. The noise would get worse the more I feathered the clutch and would start to get better as the trans warmed up.

I had to replace a wheel bearing and doing so, had to grind off the hub nut, damaging the CV axel. I figured if I was going to replace the CV, might as well replace the trans fluid. I bought Honda recommended MT fluid and noticed immediately that the fluid I was draining was not the recommended fluid (it looked like they used engine oil).

With the new Honda fluid in, the noise has almost completely went away. I still get it sometimes in reverse and sometimes when feathering 1st gear but not nearly as bad as before.

Question: Car has 180+k miles now and engine was/is well maintained, however I don't know when the clutch was replaced last. Clutch feels good and I don't want to change it out just yet. Its a major PITA and I have a lot of projects for the truck and need this car to be in one piece for at least a year. How long is it safe to drive if the throw-out bearing is making these noises?

 

The throwout bearing, if bad, can last from 10 miles to 10,000 miles. There really is no set time frame that one would last. Having the noise mostly go away after changing out the internal fluid however would make me think it was more internal, than throwout bearing. When replacing the fluid not every bit drains out completely. There is a residual amount left inside coating the parts. (Similar to an oil change in the engine) So some of the noise could be attributed to this, or possible problems from the incorrect fluid. It could still be the throwout bearing of course, but I am just listing off potential things to look at. Do you have a video of the noise you could post up?

 

I tried to reproduce it today but couldn't.

It was a like a groan/squeak/rattle all at the same time and only when the clutch began to catch. Resonated from the transmission/engine bay. No noise when depressing the clutch or any other driving scenario. Generally only happened in 1st or reverse and occasionally when shifting into 2nd if at a low speed and feathering the clutch.

Maybe not a throw out bearing? What else could be causing the noise?

 

Not 100% sure but as mentioned, bad fluid can cause erratic behavior. Perhaps a blocker ring in the synchronizer for 1-2. Might still be external, like the throwout bearing assembly.

 

Year: 2002
Make: Toyota
Model: Tacoma 4door SR5 TRD 4x4
Engine size: 3.4 w 202k miles

Problem: During most cold starts and the occasional warm start, engine runs very rough and shakes for up to 30 seconds or so. Smell of unburnt gas from the exhaust. After one or two starts like this it throws a P0300 code. Also when engine is warmed up, at idle when in Drive the engine chugs. Sort of a loud tapping noise that is separate from and slower than the typical valve tick. Tapping noise increases in frequency as I add throttle and then stops once RPM gets up above 1200 or so. If I'm getting any coolant loss, it's almost indistinguishable.

Is a lift installed: OME 881 & Nitrochargers front and rear, Very tired old leafs
Aftermarket components: intake elbow removed, Supercharger w/ 7th injector kit was installed by previous owner but removed at 170k miles. Engine brought back to stock, replaced high flow fuel pump with a used OEM one with about 80k miles on it.
Is there an alarm system installed: No
When did you first notice the problem?: chugging at idle around 5k miles ago. Misfire around 2k miles ago.
How often does it occur?: Almost every cold start for up to 30 seconds or so. Occasionally on warm starts. Haven't been able to determine a distinct pattern yet.
What have you ALREADY replaced to try and fix it?: Replaced spark plugs with OEM from Toyota (checked gaps), replaced wires with new Denso, replaced all 3 coils with new Denso, cleaned MAF, cleaned throttle body and IAC valve, replaced PCV valve, replaced fuel filter, ran 4 or 5 tanks worth of injector cleaners (Techron, SI-1, & Gumout), replaced battery because the old one was bloated and leaking.
Have you checked codes?: Received a P0420 code around 5 months ago. Cleared it and it has yet to return. P0300 code has popped up 3 times so far in the past 2k miles or so.

Any ideas of what I should check next? My timing belt is past due and I was planning on getting it replaced with pump/pulleys/tensioner, etc. soon but I'd like to try and get this misfire issue fixed first.

EDIT: I forgot to include that my front cat died at around 175k and was replaced with a weld in Magnaflow high flow cat. Figured that was worth mentioning.

 

Thanks for the detailed information. The more information given the easier it is to get an idea of where to start. You mentioned that you replaced the spark plugs. How long ago? Have you pulled them since and inspected? Have you checked ALL of the spark plug connections, as well as the coil connections for looseness and/or corrosion?

Random misfire can be a result of a timing belt that is worn. So to be honest I would suggest that you go ahead and replace the timing belt, water pump, and pulleys. Don't forget to get the kit that includes a new tensioner. Since you are already due to get this done, it would really be the best first step to make. Other things to look at are checking the exhaust when you start the engine and it is running rough. Is there any signs of white, black, or blue smoke? (NOT white steam that is a result of normal byproducts, but a true white SMOKE. You can tell the difference because steam will dissipate quickly after it escapes the tailpipe. Smoke will continue to move off) What happens if you start the truck and immediately after it starts you give it about 1/4 throttle and hold it? Does it run rough then clear up quickly, or does it continue to run rough?

 

Thanks for the input. I replaced the spark plugs about 1k miles ago but haven't yet pulled them to look at them. After I installed the replacement plugs, coils, and wires it took about 500 miles until I got the P0300 code again but I could feel it start rough semi-regularly during those 500 miles leading up to it. I found some corrosion on one of the coils where it connects to the wire so that's why I went ahead and replaced all three coils along with the wires. All the coil and wire connections seem solid and none of the connections have any visible corrosion.

I just cleaned my throttle body and IAC a few days ago and while the code hasn't reappeared, I can still feel a noticeable stumble and rough idling on cold starts and 2 or 3 warm starts so far this week. During the first cold start of the day today I tried adding about 1/4 throttle and the roughness persisted at the higher RPM for the same 30 seconds or so and then smoothed out. No smoke out of the exhaust.

Just for shits and giggles, today I checked the resistance of my MAF according to the FSM and between the E3 and THA terminals at about 70°F I was getting about 28kΩ! Could a bad MAF be causing all of these issues?

 

A bad MAF sensor could cause erratic information and fueling commands. Those commands could cause some abnormal idle and performance issues. Can you post the FSM that you followed to do the test? I would like to read the details.

 

False alarm. I was reading the page for the 2RZ & 3RZ engines. According to the correct inspection page of the FSM for the 5VZ, the resistance I'm getting from the indicated terminals is 2.1kΩ. Still out of spec but much closer to what's expected.

 

Did you blow into the MAF sensor as directed to see if there was a fluctuation? Also, what was the ambient temperature when you measure the resistance? That is what you need to know to complete this test correctly.

 

I got voltage fluctuation when blowing into it and my reading of 2.1kΩ was with an ambient air temp of about 66°F so the resistance is just a wee bit out of spec. While giving my engine another once over this morning, I saw that the intake tube and the airbox had a fair amount of grime in it so my project for this afternoon is to clean that out. Air filter still looks good as it was changed out a couple thousand miles ago when I last changed my oil.

 

Honestly I would say that a 2.1kΩ reading at 66ºF would be spot-on. The average for 68 degrees would be 2.4kΩ. I would say the MAF sensor has the correct temperature. Take a look at all of the vacuum lines and make sure none of them have any cracks. This will make the MAF signal for airflow be inaccurate, since any leak in the vacuum system would be unmetered air.

 

Bama,

I had my abs light and my parking break light go off at the same time. I also have humming at speeds starting above 35mph. I have replaced both front wheel bearings already, but not the rears. Could they be the source of my humming noise and abs light going on? I really really dont want to replace them, but i have a feeling i will have too. I have 174k and its a 2nd 4wd sr5.

 

Of course it is POSSIBLE. You would need to do a check on them though. Lift the rear, put trans in neutral, and spin the wheels.

 

Hi Bill, thanks for your service. 2007 Tacoma 4x4 access cab 4.0 auto. No lift no aftermarket. My problem is a noise which sounds like metal to metal. It occurs every time I first start off driving and it only happens once. Now once I'm driving I never hear it again at a stop light or sign but once I turn the truck off a park for even a couple minute it will occur again just once upon taking off. I have found I can control when it occurs by not completely releasing my foot from brake, I can ride with my foot lightly on brake but still moving and noise does not happen until the second I completely remove my foot from brake the noise immediately happens and then I'm good until I shut down again. Been happened about year and a half. Hard to tell where noise is coming from, a lot of times it feels sort of the middle of truck but I'm unsure. No codes have not done much to fix. Tia

 

Hmmm. First instinct would be that it is a brake pad or brake shoe issue, or possibly a caliper loose, allowing contact with the dust cover on a front wheel. Have you tried jacking up the rear, and having someone use the same method of duplicating the noise while you stand near the back and listen?