Already have a problem with the Sequoia I just bought.....

[rushthezeppelin]

Well drat already dealing with my first issue on the 03 Sequoia. So when I test drove the sequoia on Wednesday the owner was cool and let me floor it for a bit. I hit 4.5k and started getting some fluttering. I figured well maybe the governer is rather conservative on these engines (good ol Toyota undertuning). Even called a friend who has a 100 series and he confirmed that the governer kicks in somewhere around there. No other issues on the test drive and guy seemed like an honest family man who mostly works on his own vehicles and with this one had taken it in for timing belt and water pump as well as rebuilt the center diff lock actuator and replaced front diff actuator. He seemed rather excited to have a Toyota enthusiast own it and talked about how he originally had plans to build it into an overlander but decided to sell it when he got a bed camper and bought an f350 to haul that around. Basically everything checked out and the truck seemed super clean. Anways fast forward to Friday and I drive it home (about a 65 mile drive). It drove great except the one time I tried to floor it again and had the same symptoms at the same revs but otherwise was smooth as butter (at least as far as I could tell, never had a 2uz before so I don't know how they feel at tip top shape).

Anyways get home and later Friday went to the grocery store and it stalled in the parking lot. Got the odb2 reader out and it came up with a b2799 code for the immobilizer. Looked into that and after talking with my former mechanic roommate figured that the PO had simply realized that he only had one key, had another one cut and didn't have it programmed and so when I used that key it started making the immobilizer freakout (although it should have done that immediately. Anways over the weekend it happened again with no codes then a third time and three p035x codes popped up (can't remember exactly which ones) relating to ignition coils. My mind was still thrown off by that initial BCM code though and so I was still going down that rabbit hole. and so I did a ECM reset by jumping pins 4 and 13 on the odb2 this morning.

Regardless though it's happened a few more times sometimes with ignition coil codes thrown sometimes not. I started correlating it to happening only when the engine was warm (always starts right back up once it's cooled). Popped the hood later in the day and noticed that the coils were not labeled Denso (were OEM coils not labeled on these or are they likely aftermarket replacements?). Pulled one of the coils and one of the plugs and noticed the plug had a VERY worn electrode. Decided tonight to replace the plugs with new NGKs. All plugs were very worn (I'll post a pic here in a sec).
Anyways went for a test drive with roommate following behind and made it about a mile and a half from my home and it died even with the new plugs. Threw p02352 0353 and 0354 so not all of them. My research basically at this point is telling me that this had worn plugs (they were NGKs btw) and this apparently can lead to coils burning themselves out. Perhaps I was just unlucky in that the plugs got just bad enough on the drive home after picking up the vehicle that it caused the coils to start burning out rather quickly. They still have low enough resistance with a cool engine but as soon as it get's warm the resistance get's high enough to where they start failing.

Does it seem that I'm on the right track and my best bet at this point is to just replace all the coils (which I would want to eventually get them all back to Denso anyway, I know how aftermarket parts are on a lot of components with Toyota especially nowadays)? I'm worried that I'm chasing the wrong symptoms and that it could be a bad PCM but the symptoms of only failing with warm seem to be strongly leading me to the coils and the BCM code was just a red herring (it never popped that code after I cleared it and I've only been using the Toyota key). I don't want to go full parts cannon here but I never dealt with engine issues on the 4runner so I'm a little bit more of a greenie here than I am with suspension.

Here's the plugs btw. Super worn electrodes and one of them does have some minor fouling.

 

[rushthezeppelin]

I'm kind of leaning towards driving her again until she throws codes. If they are for cylinders 2, 3 and 4 again I'll swap those coils to other cylinders and see if the codes chase those coils. I'm not 100% but I think the original 3 codes were for those, really should have saved a screenshot of torque pro when it happened. If not sounds like I've got bigger fish to fry here. Wiring all seems solid in her though so I'm not sold on the idea that it's the engine harness and the PCM I can find for around the same price as all 8 coils (although I want to junk those no name coils pretty quick). I guess there's also ohm testing the coils, anyone have a good guide on that?

 

[DaveInDenver]

The chip key will either work or not. If the immobilizer doesn't recognize the key it won't start. But since it's a safety issue once the immobilizer says it's OK to start it shouldn't change it's mind and stop running.

That said I think 100 series have immobilizer issues so perhaps the Sequoia has a similar one? I seem to recall a few people over the years troubleshooting them so there should be some history to search through. My memory isn't good but I think it's just a failure to start still but I could be misremembering. The symptoms would be inconsistent ability to start.

Yeah, found one of the threads:

100 Series Intermittent Start (Key Related?)

All- One of my friends inherited a 100 series and I have been helping him get it back on the road a bit. Currently there is a strange issue with it starting. I have looked around mud and here, not really finding what I'm looking for. The situation is this, the truck ran and started fine, but...

risingsun4x4club.org

Are the keys Toyota or aftermarket? Also is it the right Toyota key? I know when I was getting new keys for my truck there was different ones, some have a punched in dot, some have a letter or something on them. New the truck would have had 3 keys. Two with black molded heads and one with a grey mold head. The difference is that black keys can be masters and grey keys can only be slaves or valet. The procedure to field program new ones requires a master key. So when you give your truck to someone the theory is by using the grey key the truck still runs but a new key can't be made. The thieves will get jobs as valets, copy the key and your address from the registration and steal it later.

Those plugs are way worn out! A new set I think is part of a baseline of any new to me vehicle. That might help the running and stalling but, like the immobilizer, I seem to think coil packs on 2UZ are known fail points. I wonder if running plugs as long as the manual says and them ending up looking that leads to premature failures. Those gaps are yuge and that's got to tax the driving circuits in the coil packs.

What is the redline on the 2UZ? Having the rev limiter kicking in at 4500 seems low to me. I don't push my 1GR that hard that often but I do sometimes wind it out. I've never actually had it start rev limiting that I could tell, but I've never tried to push it past the 5500 indicated redline.

Good luck. Work through the problems, you'll get it figured out. Techstream is a real benefit since the jump from a 3rd gen 4Runner to this means dealing more with CAN bus. It's a 21 year old vehicle no matter how you dice it things are bound to happen. This stuff is better IMO than dealing with rust. IH8FE3O4

 

[rushthezeppelin]

The chip key will either work or not. If the immobilizer doesn't recognize the key it won't start. But since it's a safety issue once the immobilizer says it's OK to start it shouldn't change it's mind and stop running.

That said I think 100 series have immobilizer issues so perhaps the Sequoia has a similar one? I seem to recall a few people over the years troubleshooting them so there should be some history to search through. My memory isn't good but I think it's just a failure to start still but I could be misremembering. The symptoms would be inconsistent ability to start.

Yeah, found one of the threads:

100 Series Intermittent Start (Key Related?)

All- One of my friends inherited a 100 series and I have been helping him get it back on the road a bit. Currently there is a strange issue with it starting. I have looked around mud and here, not really finding what I'm looking for. The situation is this, the truck ran and started fine, but...

risingsun4x4club.org

Are the keys Toyota or aftermarket? Also is it the right Toyota key? I know when I was getting new keys for my truck there was different ones, some have a punched in dot, some have a letter or something on them. New the truck would have had 3 keys. Two with black molded heads and one with a grey mold head. The difference is that black keys can be masters and grey keys can only be slaves or valet. The procedure to field program new ones requires a master key. So when you give your truck to someone the theory is by using the grey key the truck still runs but a new key can't be made. The thieves will get jobs as valets, copy the key and your address from the registration and steal it later.

Those plugs are way worn out! A new set I think is part of a baseline of any new to me vehicle. That might help the running and stalling but, like the immobilizer, I seem to think coil packs on 2UZ are known fail points. I wonder if running plugs as long as the manual says and them ending up looking that leads to premature failures. Those gaps are yuge and that's got to tax the driving circuits in the coil packs.

What is the redline on the 2UZ? Having the rev limiter kicking in at 4500 seems low to me. I don't push my 1GR that hard that often but I do sometimes wind it out. I've never actually had it start rev limiting that I could tell, but I've never tried to push it past the 5500 indicated redline.

Good luck. Work through the problems, you'll get it figured out. Techstream is a real benefit since the jump from a 3rd gen 4Runner to this means dealing more with CAN bus. It's a 21 year old vehicle no matter how you dice it things are bound to happen. This stuff is better IMO than dealing with rust. IH8FE3O4

Yeah at least I'm not dealing with rust, this things is CLEAN on the frame. CARFAX came up AZ and CO is whole life. I think you are right about the redline. And you seem to have the same thought as me that worn plugs (yes that gap is Grand Canyon levels) led to bad coils. I really think I was seeing the first signs on the test drive and the drive home was the death nail. Seller even immediately said "that's odd" before I said anything on the test drive so it seemed to be a surprise to him.

 

[rushthezeppelin]

And yes the main key is molded with one dot punched in it.

 

[rushthezeppelin]

For reference PO only had it for 20k so it's likely he never touched coils and plugs and I would think it would have happened on the test drive had he known it was an issue. Seems like it was just a rapid failure, perhaps spurned on by me flooring it on the test drive. This isn't a vehicle most people would put the pedal to the metal on.

 

[nuclearlemon]

if he works on his own vehicles, it seems odd that he wouldn't have looked at the plugs. that's baselining 101.

 

[rushthezeppelin]

He doesn't do all his maintenance but yeah. To be fair I didn't look at my plugs and coils on the 4 runner for several months after I bought it. Kind of last of me but I was more focused on the suspension rebuild.

 

[DaveInDenver]

if he works on his own vehicles, it seems odd that he wouldn't have looked at the plugs. that's baselining 101.

Total fluidectomy, plugs, belts, hoses. Heck, when Dean and I would look at used trucks we'd do compression checks and pull fill plugs to dip a finger. That was the old days when it wasn't a thousand people looking at used Toyotas and throwing cash sight unseen.

 

[IoN6]

Those plugs are way worn out! ... Those gaps are yuge...

This 👆 Like holy-wow that is a monstrous gap, I would guess over .100"

For the reving, does the 2UZ have the same stepped voltage fuel pump setup like the 1FZ? A quick look at the FSM should answer that, and have go/no-go tests for the coil packs too.

 

[J1000]

You need to baseline it. Coils are pricey so I would wait on those for now and do some other basic stuff.

Start by cleaning the MAF and clean the throttle body. Those contribute to 2UZ running rough and stalling more than anything else.

 

[rushthezeppelin]

You need to baseline it. Coils are pricey so I would wait on those for now and do some other basic stuff.

Start by cleaning the MAF and clean the throttle body. Those contribute to 2UZ running rough and stalling more than anything else.

MAF and TB can throw the 035x codes?

 

[AimCOTaco]

Aftermarket coil packs probably won't do the 250k miles the OEM's can. If you don't want to buy an OEM set I'd be diligent about logging the codes and then start moving the packs around to determine which are good and which may be intermittent at temperature. Then start mixing in OEM packs as you ID the bad ones... or borrow a known good set of 8 to test with.

I'd clean the throttle carefully, I'm not a proponent of spray cleaning it aggressively which can get solvents into the gearing for the motor/clutch components of the drive by wire, I could be crazy but I just wipe it and blow out the air paths but stay away from the pivot points.

 

[AimCOTaco]

Codes can mean a lot of things, a cylinder misfire can be the coil pack, spark plug (or fouling), valve problem, wiring, etc, etc...
Most commonly (on this engine) it's the coil pack but no guarantee. You need more "known quantities", if we know the air, fuel and filters are clean, old plugs read OK, new plugs don't help, stuff like this to narrow it down.

 

[Pz10420]

You can get the denso coils for about $50 each off of rockauto which is a decent price to me. I just finished doing them all on my 100 series about a week ago. You can actually see on the Denso coils where they machined off the Toyota logo and reboxed them. I just ordered 2 at a time over the course of a couple of months until they were all replaced. If you feel like making a drive down to Monument I'd happily give you a couple of my old ones that were still good that you could use for troubleshooting if you'd like.

 

[J1000]

MAF and TB can throw the 035x codes?

Yes and especially if it is stalling when first started up or shifted to gear it can throw codes that don't necessarily relate to the real problem.

 

[rushthezeppelin]

You can get the denso coils for about $50 each off of rockauto which is a decent price to me. I just finished doing them all on my 100 series about a week ago. You can actually see on the Denso coils where they machined off the Toyota logo and reboxed them. I just ordered 2 at a time over the course of a couple of months until they were all replaced. If you feel like making a drive down to Monument I'd happily give you a couple of my old ones that were still good that you could use for troubleshooting if you'd like.

Actually I'm going to be on monument for work today if you are available.

 

[rushthezeppelin]

Yes and especially if it is stalling when first started up or shifted to gear it can throw codes that don't necessarily relate to the real problem.

Not doing It on cold start or gear shifting.

 

[Cruisertrash]

@rushthezeppelin All new-to-you older used vehicles should get a heavy baselining. Properly gapped plugs, coil packs (or dizzy rotor & cap), fuel filter, oil change & filter, air filter, flush fill & bleed brakes (and clutch where applicable), set timing, tighten and lube all suspension (and inspect bushings), tighten driveline bolts and lube driveshafts, replace belts, loosen and then properly torque lug nuts, inspect braking system and if all looks ok throw some new brakes pads at it. I also do a full compression test and at least open the valve covers to check for sludge as part of any baselining. Your mileage may vary. This stuff will make it run better and may clear code issues before you have to go diagnosing stuff.

 

[DaveInDenver]

FWIW, the Denso part number for 2UZ coil packs looks to be 673-1303.

That may help in searching for parts. Some of the online catalogs I check show 3 in stock so it's possible that's all Rock Auto would be able to source, too.

This 👆 Like holy-wow that is a monstrous gap, I would guess over .100"

Are you really checking plug gap anymore when you can use a ruler instead of a feeler gauge?

Thinking more about this those are Denso and I'm willing to bet the original plugs from 2003. I find that the majority of the time even a diligent Yota-head ends up with NGK plugs since real Denso you have to get from a dealer or usually order online. Most places only carry NGK. That is fine IMHO and in fact my Tacoma had NGK on one bank and Denso on the other. That apparently was common back then for some reason.

But going on the assumption they are the factory plugs that would give you an indication as to the maintenance attention it's gotten. AFAIK the plugs OEMs say are "lifetime" (as though) are platinum and these are regular plugs, so 60K or 100K or something like that for an interval.