LX450 cutting out with no codes?!?!

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

wildman326

wildman326

10 Year 15 Year
Joined
Jun 23, 2008
Threads
19
Messages
73
Location
Tornado Alley.
I'm still chasing this problem and am very discouraged.

I bought an 1996 lx450 in July of this year. I drove it with no problems for about a month. Then I decided I would give it a tune up, because I didn't know the service history of the vehicle and felt it would be prudent to do so.

I purchased all OEM parts from cdan: new belts, cap, rotor, wires, air filter, oil filter, etc. About a week or two later I performed the tune up and immediately thereafter my vehicle started to sort uf cut out at around 57 mph on the highway.

I have since had the transmission checked. No problem there.

Finally I took it to the Toyota dealership. They charged me $105 for a diagnostic - and found nothing, so they suggested that they do a super clean on the injectors :rolleyes:. They waived the cost of the diagnosic and charged me $130 to clean the injectors and put some special goo in the tank. I put carburator cleaner in the tank for the next 4 tanks. To no avail.

I recently went back and the went for a ride with a tech. He hooked up a million dollar computer to the obd plug as we drove. I was able to replicate the problem, and he said that the EGR wasn't working correctly that it was going on and off and that I should replace the EGR solenoid should be replaced. I ordered one (vsv switch - I think) replaced it (which was a bitc#, btw) To no avail.

So I went back to the dealer and went for a ride again. With the same tech and computer. It got nothing at all. But the problem is still there.

Basically the car seems to cut out very briefly between the 55 and 70 mph. The problem is intermitent, but can usually be replicated at about 57mph. Sometimes it will cut out time after time like a hic hic hic hic hic up. Until I let off the gas or speed up.

The first time I went for a ride with the tech he said there were 4 misfire codes, but they were not there the last time.

I desperately want to fix this problem and don't know what to do. I hate taking my vehicles to the dealer and cannot express how disappointed I am to finally have to do so and get no help. l mean, these guys are supposed to know it all, right?:crybaby:
 
wildman326 said:
I performed the tune up and immediately thereafter my vehicle started to sort uf cut out at around 57 mph on the highway.
Click to expand...

You answered your question. Retrace your steps and make sure you didn't inadvertantly knock or disconnect or break something or forget to connect something or connected something wrong or....
 
Did you adjust the timing? If so, did you put in diagnostic mode first?

What was the gap on the spark plugs?

Please describe the cut out a bit more. Is it like a stall and its fine if you back off?

I dont have an idea, but maybe the answers to those questions will spur something.
 
cruiserdood said:
Romer, If it is like a stall and fine if you back off, what would that indicate?
Click to expand...

I am not anexpert nopr even a mechanic. I was trying to get some more information that would better describe the problem. It is obvioulsy Fuel or electrical related:doh:

I had a similar problem on my 40 that was fixed by replacing the PCV valve and fuel filter, stall but would be ok if I backed off. However, still wondering what as part of the tune-up could have gone askew here

If the spark plug wires were not in the correct order it would be noticible and I am pretty sure you would get a code.

Faulty dist cap or Rotor?

Theree is no coil, but the wire from the dist cap that plugs in halfway across the side of the engine that I can only describe as like a coil wire. A loose or faulty connector here maybe?

A bad ground that when the vehicle is going faster the movement causes a poor connection?


When you did the tune-up, did you change the air filter? If so did you take it off at the clamps or left the lid up with the hose attached. Those big hoses crack easily and give vacuum problems that affect engine performance as well.
 
It cuts out then resumes, like a hic. It happens at constant speed. None of the transmission switches make any difference (overdrive, power butons) After it happens once it will usually happen again either right away like hic hic hic, or it may take a moment to hic.

The hic is like it's starving for fuel for a brief second or there is a momentarily lack of spark.

If I accelerate or decelerate it will stop, but may start again when I hit constant speed. It never (that I can rememeber) happens when I am doing less than 55 mph.

I didn't adjust the timing.

I did remove everything and re-install. Plugs, dist, rotor, and wires.

I did not gap the plugs.

I did repladce the pcv valve.

I checked the hose from the air filter to the intake.

I have not put the vehicle in diagnostic mode, nor do I know how to do so.

I know the Toyota techs don't know anything - I'm just frustrated because I consider myself to be a competent mechanic. I've done almost all my own work on my vehicles including rebuilding the rear end and transmission (myself) on my 89 toyota truck, rebuilding the motor on same, changing the head gasket on that and several other vehicles. I'm sure many others here have done the same, I only mention it to demonstrate how difficult it is to take my vehicle to the mfing dealership.

Also, I have almost never used OEM parts to fix anything. It's cheaper to use the sh!t they sell at oreily, and I've had no problems thus far (except for wires and plugs on the 89 truck, which required bosch wires and good plugs) So, I peel off $200 to buy all OEM stuff to tune up my LX450 and I feel like I wasted my money.

I've considered replacing the cap and rotor and plugs with the aftermarket crap. Just to see what happens. Perhaps I'll even gap the plugs.
 
wildman326 said:
It cuts out then resumes, like a hic. It happens at constant speed. None of the transmission switches make any difference (overdrive, power butons) After it happens once it will usually happen again either right away like hic hic hic, or it may take a moment to hic.

The hic is like it's starving for fuel for a brief second or there is a momentarily lack of spark.

If I accelerate or decelerate it will stop, but may start again when I hit constant speed. It never (that I can rememeber) happens when I am doing less than 55 mph.

I didn't adjust the timing.

I did remove everything and re-install. Plugs, dist, rotor, and wires.

I did not gap the plugs.

I did repladce the pcv valve.

I checked the hose from the air filter to the intake.

I have not put the vehicle in diagnostic mode, nor do I know how to do so.

I know the Toyota techs don't know anything - I'm just frustrated because I consider myself to be a competent mechanic. I've done almost all my own work on my vehicles including rebuilding the rear end and transmission (myself) on my 89 toyota truck, rebuilding the motor on same, changing the head gasket on that and several other vehicles. I'm sure many others here have done the same, I only mention it to demonstrate how difficult it is to take my vehicle to the mfing dealership.

Also, I have almost never used OEM parts to fix anything. It's cheaper to use the sh!t they sell at oreily, and I've had no problems thus far (except for wires and plugs on the 89 truck, which required bosch wires and good plugs) So, I peel off $200 to buy all OEM stuff to tune up my LX450 and I feel like I wasted my money.

I've considered replacing the cap and rotor and plugs with the aftermarket ****. Just to see what happens. Perhaps I'll even gap the plugs.
Click to expand...

Unbelievable!:eek: The kind of problem you have and the OBD with the tech on board is exactly what the tool was designed to do-ID and fix intermittent problems. And you can replicate the problem. That tech & dealership are totally incompetent. Write a letter to the dealership manager (not service manager) emphasizing your frustration:mad:, lack of confidence:confused: and wasted money:mad:. To him, you're a potential buyer and if he doesn't make it right, write to corporate. Hey you've used OEM parts, right? WTF! :meh:
 
wildman326 said:
I did not gap the plugs.
Click to expand...

Most of the time the gap is good from the factory, it does pay to check the gap. Note the comment on too wide a gap. Could this be a miss at high speeds? Thinking though this would at least set a code readable by the OBD II.

Do you have your old cap, rotor and wires. I tend to hold on to that stuff for spares and swapping out comes in handy.

From Spark plug - Wikipedia, the free encyclopedia

The gap adjustment can be fairly critical, and if it is maladjusted the engine may run badly, or not at all. A narrow gap may give too small and weak a spark to effectively ignite the fuel-air mixture, while a gap that is too wide might prevent a spark from firing at all. Either way, a spark which only intermittently fails to ignite the fuel-air mixture may not be noticeable directly, but will show up as a reduction in the engine's power and fuel efficiency. The main issues with spark plug gaps are:
  • narrow-gap risk: spark might be too weak/small to ignite fuel;
  • narrow-gap benefit: plug always fires on each cycle;
  • wide-gap risk: plug might not fire, or miss at high speeds;
  • wide-gap benefit: spark is strong for a clean burn.
A properly gapped plug will be wide enough to burn hot, but not so wide that it skips or misses at high speeds, causing that cylinder to drag, or the engine to begin to rattle.
 
Couple of ideas..... again these are just food for thought:confused:

1---Could this issue be related to the bundle of wires located near the firewall, the ones near metal heater pipe.
The bundle that has the metal heat wrap around them, maybe something grounding out....?????

Or maybe the

2----Fuel pressure regulator......


Good luck, you made the right decision doing what you did now just find the simple thing thats causing the glitch.
 
If you went to the dealership and they did not fix your problem then you should go to the next chain of command....regional corporate. It's like going to the doctor and being mis-diagnosed. They should do everything within their power to find the problem and not charge you a dime....and there is NO excuse for taking it to an authorized Toyota dealer and still have the problem afterwards.
 
Clutchee said:
Couple of ideas..... again these are just food for thought:confused:

1---Could this issue be related to the bundle of wires located near the firewall, the ones near metal heater pipe.
The bundle that has the metal heat wrap around them, maybe something grounding out....?????

Or maybe the

2----Fuel pressure regulator......


Good luck, you made the right decision doing what you did now just find the simple thing thats causing the glitch.
Click to expand...

Now thats a thought, there is a small vaccum hose from the throttle body to the Fuel Pressure regulator(FPR) that can easily be knocked loose when doing a tune up. Might be something worth checking.

The FPR is above the alternator
 
Clutchee said:
1---Could this issue be related to the bundle of wires located near the firewall, the ones near metal heater pipe.
The bundle that has the metal heat wrap around them, maybe something grounding out....
Click to expand...

Good suggestion. You can inspect this main engine wiring harness and try to wiggle it while the truck is running to see if you can change anything.

-B-
 
Dont forget to post up your progress and final solution
 
Busy as can be, so progress is nil.

However, I did look at the vacuum lines. Again. And I still can't see anything off.

I haven't had time to take off the rotor or cap etc. But plan on doing so.

Will post progress when I have a chance.

Thank you for all the suggestions, I really appreciate it!!
 
OK.

Time for an update.

Hope the lx450 ninja reads this and figures it the #uck out.

I've travelled from Wichita, KS to Charlotte, NC, to Columbia, SC, to Nashville, TN, to Richmond, KY, to Atlanta, GA in the last week and I can tell you that this is a major pain.

It really only happens when the engine is not loaded down. So, if I am accelerating or going up hill it never (never) happens. However, if I am decelerating, or going down hill it does.

Uh, Uh, Uh, Uh, Uh. like that.

I have replaced the plugs, cap, rotor, and wires (i think) with aftermarket. Absolutely no difference. I saved the semi-new OEM stuff to use later.

Based on the consistancy of when this occurs I don't think it's anything loose or cracked.

Could it be the MAF (air flow sensor)?

A mechanic told me to check this I could pull the plug on the sensor while the truck was running. If the problem wnet away, then the MAF was the issue, if not, not. Well, I pulled the plug and the truck died immediately. So . . . .
 
I doubt it's the bundle of wires. Doesn't seem logical that they would ground out at exactly the same time like that.

Fuel pressure Regulator? OK. where is that?

Really, I'm so f'n sick of this f'n problem that I'm ready to f'n throw big money at it just to make it go away. Like buy a used motor and swap the f'n thing. I'm not afraid to work on the f'n car. But it makes me very very fussy when I don't know what to do. And the dealership doesn't, and no one on here has had a similar issue.

I mean, really, am I the only guy on the face of the planet that has had this issue? Does that make me incredibly unlucky or just super stupid?
 
sudden loss of power with sudden revival on change of throttle position.
+
no codes
=
Fuel pump relay
 
You must log in or register to reply here.

Share this page

Back
Top Bottom