Easiest way to check timing belt is timed correctly? (1 Viewer)

[Beau]

Hi everyone, having recently bought a 1999 lx470, I am wanting to verify the timing belt is properly timed as I've read other post on mistakes made in the past. What's the easiest way to check the timing of the engine? Can it be done via techstream?

The reason for checking is the power seems a little low, and it seems to struggle to do 80mph on the highway. Getting about 220 off a 20 gallon tank.

Thanks in advance

 

[gregnash]

I have heard of being able to pop the cover off the passenger side (semi-easy access) but have not confirmed that... Hopefully @2001LC will chime in with something good.
And describe what you mean by struggles to get up to 80mph on the highway?

 

[Beau]

Seems to have more power on the bottom end than the top end, when from what I've read it should be the opposite way around. I feel like I'm really pushing this thing, 75% + throttle to get it to 80mph. I've not taken it beyond that because it just feels like it's lacking some power. I had the cruise set to 75mph and when going over a little overpass it downshifted and revved high just to maintain speed.

My other diesel cruiser with 110hp weighing a little over 2 tons will pull to 90mph with 50-60% throttle input. Granted, I can't compare the two, but it just seems a little gutless.

Checking the timing won't cost me anything apart from time, so it's a good place to start before chasing other avenues.

 

[gnob]

Check out and see how dirty your MAF is

 

[Beau]

MAF was relatively clean, as was the throttle intake.

Is there any videos out there with a stock 100 series with 33" tires, doing a 0-80 mph. That would give me a good reference. And this would have to be for the 4 speed models. I've looked at stock 0-60 on youtube and those things seem to rev very well compared to how sluggish mine is.

 

[gregnash]

Could be something like the torque converter in the tranny going out causing it to lug a bit.
I have a 98 LC with same setup and she seems to accelerate quite nicely. Definitely faster than my old 2F powered FJ60 so not much to compare against. Gearing for your Prado could be significantly different too to help with diesel/turbo setup and whatnot.

Fact of the matter is that these aren't speed racer vehicles. If you are taking miles to get up to 80mph, then that would indicate something is wrong. But if it is just not jumping on it and you are at 80 from whatever speed, that could be indicator of something else happening. Go through and check to make sure that brakes aren't dragging causing power loss, no bad belts or anything like that, drivelines and diffs are all changed out. Etc. Sounds like time to go through and do some baselining if its yours already.

 

[Beau]

Any chance you could video (safely) a 0-60mph run at some point? It would put my mind at ease that it's not a problem, and that's just the pace of these trucks. Like you said it doesn't take miles to get up to speed, but it doesn't exactly get there quick either.

Surprisingly the gearing aren't too different. At 60mph in my prado, I'm at 2k revs which is pretty similar in the LX. Only difference is the prado properly has twice as much torque at that RPM vs the LX. Speed wise, it drives very similar to my 1999 2.7 3RZ single cab pickup truck with 34" tires and stock gearing. Even then the tacoma is more peppy.

 

[KFunk740]

Dumb question, but are you hitting the 'ECT PWR' button by the shifter?

I got worried about my '99 when I first drove it home from Indiana and realized it pretty much never got over 2K or 3K rpm, then realized I needed to hit the ECT PWR button to get it to rev freely. Then it really took off if I put the gas pedal all the way down. Not super fast, but you could feel it pulling fairly well.

 

[KFunk740]

But to answer your question about checking time, gotta double-check whether there's crank timing mark by the crank pulley on the plastic cover. I can't remember, and LC is at home. If the timing mark is there, then its a matter of just pulling the little cover over each cam sprocket. I think the cam sensor will come off with the drivers side cover, so be careful with it and its wire routing. Line up cam marks and check with crank pulley mark. The cam timing marks in the casting were just a hair off on mine from the factory it appeared though, so don't expect it to be completely perfect. If it were a tooth off, it would be waaaay off mark.
If there's no crank timing indicator on the plastic cover and it requires removing the lower plastic covers to see the mark in the casting, then don't bother unless you're real desperate. You'll end up going almost as far as a full timing belt swap.

 

[Beau]

I've driven with it both on and off, and whilst it does hold the gears longer and give the appearance of a quicker get go, up top in 4th gear is where it seems to struggle. Around town, I don't notice the lack of power.

As mentioned it looks like I can wiggle the passenger side cover off, not sure about the drivers cover. Can the bottom crank mark be seen without removing anything? If I can line up the crank to TDC and see where one out of the two cam shaft pulley aligns that'll give me what I need to confirm timing.

Alternatively, is there anyway of reading TDC via techstream? That way I could see what the computer is seeing, and check what the engine is really at?

 

[BadReligion]

I would imagine that it would run VERY poorly if you are even off by 1 tooth on either cam. Like bad ignition coil bad. You would probably see a CEL too.

I had the fan, serpentine belt, and a few other things off before removing my covers so I don't remember everything that was in the way. Looking at my engine, I think it would be tough to remove the DS cover without removal of the hard coolant line going to the oil filter housing.

If you get the cam covers off, you can see the timing marks on the cams themselves, and compare to the one that should be visible on the crank pulley. They should all be in the same relative position. If you are off by a tooth, then the mark is off by at least 10-15mm. In other words, its pretty obvious.

 

[Superdude]

I would imagine that it would run VERY poorly if you are even off by 1 tooth on either cam. Like bad ignition coil bad. You would probably see a CEL too.

I had the fan, serpentine belt, and a few other things off before removing my covers so I don't remember everything that was in the way. Looking at my engine, I think it would be tough to remove the DS cover without removal of the hard coolant line going to the oil filter housing.

If you get the cam covers off, you can see the timing marks on the cams themselves, and compare to the one that should be visible on the crank pulley. They should all be in the same relative position. If you are off by a tooth, then the mark is off by at least 10-15mm. In other words, its pretty obvious.

To add to this. I had a V8 4Runner (same engine 4.7) slip a tooth on the timing belt. I did have a CEL a day after I noticed the truck running slower. I was still able to get up to highway speeds, but it was noticeably slower/struggling. I pulled both timing covers off and sure enough, the mechanical timing was off. New TB/Water pump install and I was good to go.

 

[BadReligion]

To add to this. I had a V8 4Runner (same engine 4.7) slip a tooth on the timing belt. I did have a CEL a day after I noticed the truck running slower. I was still able to get up to highway speeds, but it was noticeably slower/struggling. I pulled both timing covers off and sure enough, the mechanical timing was off. New TB/Water pump install and I was good to go.

Interesting...did it slip on its own? If so, how old was the belt and was it OEM?

 

[Superdude]

Interesting...did it slip on its own? If so, how old was the belt and was it OEM?

It did slip on it's own. It was an 05 VVT-i model. Was the OEM spec belt Mitsuboshi and that's what I replaced it with too. Never had a problem after that. I chalked it up to worn tensioner.

 

[Beau]

Ok, if the CEL would show and it would run THAT rough, I think I am fine. I did however read a thread that one guy had where it was off two teeth and no CEL was shown. I think I'll try and get the passenger side cam cover off and see if I can align that with the crank. If those two align, it's likely the DS cam is fine too.

Quick question - with running 33" tires now, do I have to compensate for additional miles not being calculated at the Odometer?

 

[gregnash]

Ok, if the CEL would show and it would run THAT rough, I think I am fine. I did however read a thread that one guy had where it was off two teeth and no CEL was shown. I think I'll try and get the passenger side cam cover off and see if I can align that with the crank. If those two align, it's likely the DS cam is fine too.

Quick question - with running 33" tires now, do I have to compensate for additional miles not being calculated at the Odometer?

I say invest in something like a small OBDII scanner so that you can check to see if codes have been cleared recently. My buddy was the one that suggested this to me as he had almost purchased a truck that ended up coming from a shady person who was clearing codes after every usage before a potential buyer would come by. This scenario had codes showing up a couple days later as it was something that would take a few usages of the vehicle before popping up (think bad O2 or cats if I remember correctly). My brother has a similar issue with a bad o2 sensor on his newer explorer. This will not allow the remote start to work because of the CEL and dealership wants something ridiculous to replace the o2 sensor. I gave him a spare BlueDriver bluetooth OBDII so he can clear the code as needed (about once a month).

As for the 33s, I am running 285/75r16 on my truck and find that I am about 3-5mph off from speedo. There is a bluetooth correction device that is offered by an Aftermarket company (can't think of name right now) that one guy recently did in his 100 and previously had done in his 80 with good success. There is also the "Yellow Box" that you can wire in and manually adjust switches to make the compensation happen.