3.4ltr timing out? How do I adjust it?

[hkt_up]

Firstly, this is my first post. Have been an avid "listener" for a while now and have moded my '98 Surf using advice gained from this forum. Current setup is OME 881's up front with 891's in the rear along with OME Sport shocks, a 40mm body lift, rear ARB air locker and 305/70/16 BFG A/T KO's running on 16x8's. The advice and information gained from this forum has been invaluable, thanks guys.

The trucks been lacking power for a while now, main symptom is that it won't accelerate or gain revs on slight inclines or in boggy sand (basically when under slight load) and won't change down unless floored. Transmission seems to be OK and changes when shifted manually or driven hard.

I finally had a chance to get it in to the shop for a check up. They have replaced plugs, removed the blocked up catalytic converter and turned the fuel filter around that the previous owner had installed backwards. This should all help somewhat.

The biggie is they also mentioned that the timing is out. No drama I figure, adjust it. But they then said that it is not adjustable nor a problem they had come across before. Anyone here able to shed any light on adjusting the timing on a '98 3.4ltr V6 please?? Is it possible that when they did the timing belt, pulleys etc a few months back something was done wrong which mucked up the timing? Any other suggestions?

Any advice much appreciated.

 

[Spencer]

I know the shop SAYS timing is out. But if it's not down shifting you need to tighten the cable that goes to the transmission

 

[TheDurk]

They turned the filter around? To me, that means all the crud it filtered while it was in backwards is on its way to your engine. Unless it was only in backwards for like a week, I would have started over with a new one. I suppose they may have tried to flush it, but that would not be easy.

The ECU adjusts the ignition timing continuously. I'd want to know WHY the shop thinks the timing is off. Gut feeling? Code? Did they pull the upper cover and point a light at the crank or cam and decide they didn't like the number? It's off at what RPM?

The timing belt affects VALVE timing. One would think your shop is talking about IGNITION timing. There is a big difference and a lot of people don't understand the difference between the two. Which is it?

The one big concern I would have is if somebody failed to properly tighten the crankshaft bolt after the timing belt job. If you are misfiring and there is ANY hint of a visual wobble in the crank pulley, get it checked out NOW. The consequences of this can be seriously painful to your engine and wallet--it has happened to others. See this thread on YT:Linky

Sorry I can't be more helpful, but your post only makes me want to ask questions.

 

[hkt_up]

I know the shop SAYS timing is out. But if it's not down shifting you need to tighten the cable that goes to the transmission

Thanks Spencer, I'll look into that as well.

 

[hkt_up]

They turned the filter around? To me, that means all the crud it filtered while it was in backwards is on its way to your engine. Unless it was only in backwards for like a week, I would have started over with a new one. I suppose they may have tried to flush it, but that would not be easy.

Sorry, they put a new one in, the right way around

The ECU adjusts the ignition timing continuously. I'd want to know WHY the shop thinks the timing is off. Gut feeling? Code? Did they pull the upper cover and point a light at the crank or cam and decide they didn't like the number? It's off at what RPM?

They pulled the cover and put a light on something in there. That's whats got them confused as they are not aware of A/ what's caused it to be out or B/ how to adjust it.

The timing belt affects VALVE timing. One would think your shop is talking about IGNITION timing. There is a big difference and a lot of people don't understand the difference between the two. Which is it?

It's ignition timing as you thought.

The one big concern I would have is if somebody failed to properly tighten the crankshaft bolt after the timing belt job. If you are misfiring and there is ANY hint of a visual wobble in the crank pulley, get it checked out NOW. The consequences of this can be seriously painful to your engine and wallet--it has happened to others. See this thread on YT:Linky

Here's hoping it's not that serious, but I will definitely raise this with the shop.
Thanks a bunch for your help

Sorry I can't be more helpful, but your post only makes me want to ask questions.

Good questions though!

 

[TheDurk]

Good questions though!

Ok, thanks for clearing that up. Now, since you are in NZ, we need to know if this is an OBDII equipped truck. All of ours are, but other countries may not be. I retired my timing light when I got my 4Runner, but the lack of on-board diagnostics may be why your mechanic is still using one. If it is, please confirm that no Check Engine light is on.

 

[hkt_up]

TheDurk,

Thanks again for your help, I'm guessing OBDII is some sort of onboard diagnosis? If so, then no mate, we don't have it. But problem solved, not a loose CS pulley but the actual toothed gear that the timing belt runs on was flogging out and loose on the key. Not sure what caused this but the local Toyota dealer seemed to think it was a relatively common problem, to the point that they carry the necessary parts in stock. Not sure if it's common as a result of error on the part of the guys changing timing belts not reinstalling everything correctly, or bad / complicated design of the key/gear interface, or a combination of the two? (which gets my vote) Either way, thankfully they've located the problem and it's been fixed, yet to test drive or get the bill so the jury is still out on how I'm feeling about my local shop at this point. Will keep you posted.

 

[02SE]

I'm glad to hear that the problem is likely fixed.

On a different note, I know there is some incredible scenery in New Zealand. If you don't mind posting pics, I'm sure they would be appreciated.

 

[TheDurk]

TheDurk,

Thanks again for your help, I'm guessing OBDII is some sort of onboard diagnosis? If so, then no mate, we don't have it. But problem solved, not a loose CS pulley but the actual toothed gear that the timing belt runs on was flogging out and loose on the key. Not sure what caused this but the local Toyota dealer seemed to think it was a relatively common problem, to the point that they carry the necessary parts in stock. Not sure if it's common as a result of error on the part of the guys changing timing belts not reinstalling everything correctly, or bad / complicated design of the key/gear interface, or a combination of the two? (which gets my vote) Either way, thankfully they've located the problem and it's been fixed, yet to test drive or get the bill so the jury is still out on how I'm feeling about my local shop at this point. Will keep you posted.

The toothed gear and the pulley I mentioned both sit on the crank and share the same key; if the gear was loose, so was the pulley in front of it and the reason was the bolt I was talking about. If I'm sitting on the jury, the verdict is GUILTY! I'd try and make them eat the cost. Definitely read that thread I posted. That bolt needs Loc-Tite and 218 ft-lbs. of torque which is big-time torque. This is only a common problem due to ignorant mechanics who don't torque to spec. Ask them how many ft-lbs they torqued it to; if you feel snarky, make him show you a wrench that goes up to 250 ft-lbs.

Yeah, OBDII is the US on-board diagnostic spec that went on all cars in 1996. Makes use of a timing light pretty much obsolete. I don't think our engines even have a degree scale marked to read the timing with precision, although there are some specs in the Service manual.

Anyway, glad you are back on the road and that no damage was done to your crankshaft.

 

[BTO]

You should get confirmation of what timing is out. It could be valve timing the shop was talking about. That would cause the symptom you speak of. If the previous owner installed a gas filter backwards then it's easy to imagine they got a timing belt on one tooth off.

Ignition timing is not adjustable. It is set by a crank position sensor and the computer which also checks other sensors.

 

[97-4xFunner]

Good call Durk. If I were in hkt_up position and they were going to stuff me with the bill, I would ask them for the torque spec. I wouldn't get rude but I wouldn't let them dodge the question either. This is all under the assumption that it's the same shop that replaced the timing belt, and that job wasn't performed all that long ago. I changed the timing belt on a 3.4 a while back, and for the toothed gear there isn't anything complicated that a profesional mechanic couldn't handle.

 

[hkt_up]

I'm glad to hear that the problem is likely fixed.

On a different note, I know there is some incredible scenery in New Zealand. If you don't mind posting pics, I'm sure they would be appreciated.

Cheers O2SE, most our off-roading is coastal stuff to get access for diving so no spectacular back country scenery sorry. Some beautiful coastline though. Will have a dig around and see if I can find some decent images to put up.

 

[hkt_up]

To update things, the shop came to the party with parts and labour related to the crankshaft timing belt pulley issue. With this sorted and the catalytic converter removed, fuel filter around the correct way and new plugs she nows runs better than ever. I paid for plugs, fuel filter and a bit of labour

As for some photo's O2SE, don't often carry a camera but must get into the habit. Here's a few random shots from around the coast south of Wellington NZ.