2007 Toyota 4Runner - Timing problem

TL;DR: I have REPEATEDLY had timing issues crop up in my 4Runner, even after replacing the timing chain and timing set, replacing the engine, and replacing the engine AGAIN. Am I just THAT unlucky, or could something else be causing the timing issue? Anyone ever deal with REPEATED timing issues? Anyone ever successfully fix a timing issue?

Commence my tail of woe: My beloved 2007 Toyota 4Runner started showing a check engine light from time to time about a year ago. My partner and I pulled over, we got it checked out, but then…it went away. We didn’t see it for a while, but then it came back. We got it checked out a few times, and most mechanics suspected the timing chain was getting old, or maybe the oil pump was failing. Either would be an expensive fix. The light went off again, so we put it off.

Well, we were on another long road trip this fall, 300 miles from home, when the check engine light came back, and the oil light started flashing. Well, having long suspected timing chain + oil pump, we were very worried! We brought it to a mechanic, and he gave us the bad news: Timing chain. The computer codes said “over retarded timing,” I believe.

The car ran fine, as far as we could tell. No weird smells, no weird noises…but we’d known about this possible timing chain for a while, and the car had ~250,000 miles. Not wanting the engine to destroy itself, we got a hotel room and had the mechanic replace the timing chain and other parts, a whole “timing set” and the oil pump just in case. A few days later we drove away…and got the check engine light in 40 miles. Bummer. And this time we heard a weird clicking and then a bad knocking. There hadn’t been a knock before! What had happened?

Back to the hotel, and back to the mechanic. We left it with him and took a bus home to wait for the repair this time. Maybe they’d made a mistake because they rushed it last time? They assured us they could fix it. This time the codes said “over retarded timing” AND “over advanced timing.”

Well…they couldn’t. They said the engine was all sludged up and had thrown a rod. They told us we needed a new engine. $#@$$#154WTT#$!!! Rats. This is what we wanted to avoid by getting the timing chain replaced right away! After weeks of talking with the mechanic and working our butts off to scrape some funds together, we decided to get the engine replaced. We got a junkyard engine because that’s all we could afford. Still cheaper than a new car, so what choice did we have? Also we love that 4Runner. We wanted it back. The mechanic would replace our engine, but he’d transfer over our brand new timing set.

A month and a half later (most of that was just us trying to figure out what on earth to do), the car was ready. We borrowed a friend’s car to go retrieve ours, started driving, and…well, we made it 150 miles this time, but right after filling up, the check engine light was back AGAIN. And the code was…over retarded and over advanced timing!!! WHYYYYYYYYY.

Well, we weren’t going back to that mechanic again. Apparently timing chains are hard to do correctly. Please correct me if I’m wrong, I’d like to know for sure. We got the car towed home, only to find out, well, we could still drive it, but yeah, there was something wrong with the timing, the new chain was stretched (how??), and the engine wasn’t so great.

So we got the engine replaced AGAIN again, by someone here at home, without anyone touching the timing chains on the “new” used engines (junkyard engine was warrantied, so we got another junkyard engine in its place). This time we drove away…no code! And the car was so quiet! Phew! We drove around casually with no issues. No big trip yet.

That lasted until I washed the car. Check engine light was back again. This time the code was a bit different, and I know the number this time: P0016, cam shaft position sensor, bank A. But you know what can cause P0016? TIMING. ISSUES. ARRGGHGHG!!! Please, no!

This code comes on, sticks around for a while, and then tends to go away on its own. Could it just be a sensor? Or has my timing chain jumped again? Could it be something else that’s caused THREE different timing chains to jump? I think the timing set included guides and a tensioner pulley, but then I guess I got another used engine, whose timing area didn’t get messed with. Am I just super unlucky? Do I have to redo the timing on my new used engine too? This is getting ridiculous. I want to save my 4Runner, guys! I’m about ready to fix the timing chain myself, if that’s what’s wrong again. I certainly don’t have the money to pay ANOTHER guy to do it WRONG. D:

Has anyone ever had a timing issue successfully fixed by a mechanic? Has anyone done it themselves? Any troubleshooting tips? I need help.

Nice to see a post at the other end of the Bell curve from “My engine broke.” Hope the mechanics here have some insight.

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It would be useful to know which engine the SUV has…You don’t tell us that.

A P0016 error code is likely these items below.

  • Mechanical timing fault
  • Blocked oil passage
  • Low oil level
  • Faulty Intake (‘A’) Camshaft Position (CMP) Sensor
  • Faulty Crankshaft Position (CKP) Sensor

If that is the error code you’ve been getting all along… with no others…

If the 1st engine was determined to have oil sludge, are you diligent about changing the oil regularly? Sludge will clog the timing chain oil-pressurized tensioner and not properly lubricate the chain.

Do you check the oil level regularly? Low oil level can cause timing issues, as you can see.

You luck with this SUV has been pretty poor but you need to tell us a little more about how you maintain it as well as vehicle specifics… miles on the used engine, miles on the SUV now, 4WD? or 2WD? Your maintenance habits. Post back and we’ll try and help.

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I think it would be useful if you knew exactly what was replaced, and exactly what was moved from the old engine to the new engine. You might just be moving a defective product so the problem remains. Or, if it is one of those “they all do that” devices, it may not be the entire engine problem.

All I can say is…
Most engines do get neglected with infrequent oil changes or not checking the oil level regularly.
If an oil pump is worn out then the entire engine is worn slap, dab out.
Maybe a worn out crankshaft/bearings was the actual cause of oil pressure issues. OIl light flashing means dxxn near out of oil or the oil pressure sucks horribly.
As a mechanic I’ve replaced chains with no issues afterwards.
No way on God’s Green Earth would I install a new chain set/oil pump on a quarter million miles engine which had the tell-tale signs of being near the end.

With junkyard engines those are always a coin flip at best and yes, I know the bone yards always “guarantee the engine to be good”. They say that about everything on their lot which they have likely never heard run nor have they driven.


Over retarded timing faults are caused by sticking variable valve timing solenoids, dirty oil and sludge. Replacing the timing chain in a sludged engine will not help with this problem but it does help to line the pockets of the good independent mechanic.

I check the oil from time to time, maybe every 1-2 months. I get the oil changed every 3000-5000 miles, preferably 3000, but I do admit 5000 has happened on a few occasions. I ask for full synthetic. I don’t change the oil myself because the service is relatively cheap, but I’ve been thinking about starting to do it myself. Any recommendations on which type and brand of oil are the best for high-mileage engines? I’m actually still confused about that. :stuck_out_tongue:

The “new” junkyard engine has 150,000 miles or so. The whole car has 250,000 miles. It’s a 2WD. Anything I can maintain/replace myself (brakes, rotors, calipers, wheel bearings, alternator, battery, that’s the list so far), I do. I try to listen to my car and research what’s going on if I ever hear a weird sound or get a warning light.

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That is not even close to what you should be doing. At the very least check the oil level every fuel fill up . Just the correct weight oil is all you need and if it says High Mileage fine. Don’t really see the need for full synthetic unless the cost is not a factor.

I wish I knew more about what was replaced at each step. The mechanic described it to me, and the bill describes it too, but not everything was written down. To my knowledge, here’s how it went:

Step 1: Timing chain set (whatever that includes??? Maybe chain, guides, and sensors), oil pump, and some gaskets were replaced. It was mentioned to me that the tensioner was not replaced.

Step 2: Engine was replaced by used 165,000 mile junkyard engine, but timing set and maybe the new oil pump were transferred over. Solenoid was replaced, because previous was faulty.

Step 3: Used engine was replaced by a different 160,000 mile junkyard engine, pretty much a straight swap. Timing compartment was left as-is. I think a small part or two were transferred from my original 250,000 mile engine. They told me what it was, but I don’t remember now. :B Maybe a sensor or a valve part? I wish I could remember. It doesn’t say on the bill. Anyway, to my understanding, everything inside the timing compartment belongs to the 160,000 mile engine.

I wish I knew that then! :stuck_out_tongue: The sludge problem had been mentioned to me before, by other mechanics, but they didn’t say what to do about it beyond getting my oil changed regularly (which I did), and I didn’t know it could kill my engine like that. D: I could’ve replaced the whole thing at the beginning of this whole ordeal and maybe could have afforded an actual new engine! xD

This brightens my day and gives me hope. <3 If my “new” used engine DOES have a timing issue, and isn’t sludged up (how do I check THAT?), then maybe I’ll try replacing the chain–or getting someone to replace it for me. I know it’s super labor intensive, and therefore also very expensive, so that’d be a big decision to make.

Man, I don’t know ANYONE who checks the oil every fuel-up, but that sure would be ideal, wouldn’t it? xP Okay, I’ll try to check more often.

What’s the right weight? I’ve seen varying answers on the web. I think I’ve seen 5w30 the most, but I’ve also seen 0w20 and other stuff in between. What’s the BEST for a high-mileage engine?

If you still have your owners manual the correct weight will be listed . It might even be on the oil fill cap . Or you could ask the shop who did the engine work.

Just for fun I put ( oil for Toyota 4Runner ) in google and got this ( 5W30 ) .

Like I said, that’s what I’ve seen the most often, so if you think that’s right too, then great! I’ll probably use 5W30. :slight_smile: I wonder why others have said other weights, but you know, maybe it doesn’t matter. 5W30 it is.

I have switched to sythetic oil in vehicles with as much as 90k miles. Mobil 1 brand.

The 90k engine turned the oil black in 1000 miles so I changed it. Blackened the oil in 2k miles so I changed it again. That change went 3500 miles. Clearly the Mobil 1 had more detergents and removed a lot of sludge. Many miles later I did a head gasket and saw hardened chunks of sludge in the lifter gallery but the overall the engine was clean inside.

A little more cost for the oil but it surely couldn’t hurt and may help.

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I tend to not think too highly of a mechanic who replaces an oil pump on the theory that it is worn out. Look at it this way. The oil pump is the first thing in an engine that sees motor oil upon startup and if an oil pump is worn out that would mean everything following would also be worn out even more. The only bad oil pumps I’ve ever seen were ones that were destroyed by a thrown connecting rod or ones wiped out by a total lack of motor oil.

And worn timing chains are caused in most cases by neglected oil changes or by oil quality issues. Chains do not hold up well with dirty/oxidized oil or by thermal breakdown of the oil.

A lot or all of these problems I would chalk up to being high miles engines. Anymore, I don’t even trust low miles engines from the salvage yards as the majority of those are neglected units.
Tough thread to read as it’s a bit heartbreaking to read about so much time, aggravation, and money being expended on this.


Update: Car is still running fine but code P0016 has been on a long time now. I tried replacing the camshaft position sensor, which seemed like it worked because the light went off for 4 weeks. :open_mouth: But then the light came back and has been on for like a month. :confused: It snowed a lot where I am now, so I don’t know if the change of weather had any effect or if the problem is getting worse. Annoying because I was really hopeful during those several weeks after replacing the sensor!

Other ideas: Crankshaft position sensor, ancient spark plugs, oil control valve, or the big baddie himself, the timing chain.

I’ve heard you can check the timing chain stretch by peaking through a four-bolt window, so I went and looked today, picture attached. I’ve heard shiny is bad because it means the tensioner could be fully extended due to timing chain stretch. And apparently that’s a known problem for 2007 Toyota 4Runners! Alas, lucky me?? :anguished: Anyone have a feel for how the tensioner should look here? Also, how’s my sludge level? My reaction right now is ew, that looks pretty sludgy. Maybe I’m not changing my oil often enough. :confounded:

I’m sympathetic to your situation.

Having said that…you have a whole lot of unknowns going on, especially with this (current) engine. Since it came from a junkyard, you have no idea how it was maintained previously. So if there is sludge and other issues…it was likely due to the maintenance of the engine prior to you.

Personally… I wouldn’t put any more money or time into this vehicle. It’s 14 years old, has 250K miles on it, and you’re on your 2nd junkyard engine. This situation is not going to get any better.

Good luck.

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