Tracking down a bank specific misfire 2,4,6,8 (1 Viewer)

[Supergoji]

Hey ladies and gents.

2002 LX470
210k miles

Trying to eliminate a misfire on the pass side bank.
Misfire codes for 2/4/6/8
The majority of the codes were at Cyl 2 and the Trac /vsc lights are on.

Replaced coil packs and plugs. (all 8)
Problem persists.

Removed pass side cat and 02 to check if clogged cat, cat was fine
Problem persists.

Replaced injectors (2,4,6,8), problem disappated somewhat
but intermittently returns.
Problem persists.

Smoother in higher rpms.

At this point I'm thinking it's one of the below.
Fuel pump
Fuel filter
Intake manifold gasket.
Jumped a tooth on the timing belt (which needs to be replaced anyways.)

At my wits end here.
Help!!!

 

[atnolan94]

I think you can narrow the search a lot here. It would be highly unusual for all 4 injectors, or plugs, or coils to go simultaneously all on the same bank while the other bank is ok. A fuel pump or filter issue would cause issues on all 8. I suppose intake manifold is possible but that’s a pretty small failure rate part.

Timing jumped a tooth is possible, and most common in this situation. Electrical issues in the bank’s harness could be possible.

 

[2001LC]

We've a lot of problems with boot leg spark plugs and coils from China. I'll assume you have real Denso or Toyota Denso coils and real and proper spark plugs, If not you'll chase this.

Since running; start with vacuum tests. Then move onto compression testing. Depending on how these look, move to checking timing of belt.

 

[Kofoed]

Possible anti knock sensor bad or wiring open circuit? There is one sensor per side.

 

[nissanh]

As atnolan94 said the miss fire is only on one bank so fuel pump, injectors, MAF, manifold gasket etc., that are common for both banks are not the issue.
Could be bad timing. Did you do any timing work recently? Also any electric welding on muffler with ground mounted to frame?

 

[97 AZ LC]

I think it's unlikely that it's timing but I would start there, just because the passenger side timing belt cover happens to be the easy one to take off.

 

[Eicca]

The only electricals that are truly isolated to one bank or the other are O2 sensors and knock sensors. If there’s a problem with wiring for coils or injectors it’ll manifest itself in both banks because the wiring is designed split between sides.

A mechanical issue is most likely. Pull the covers and check timing.

 

[Supergoji]

Harness seems good.
I'll inspect the timing tomorrow.

What am I looking for incase it jumped a tooth?

Yes, I used all OEM parts not the China reps.

Electric welding?

Knock sensor is under the intake?

 

[97 AZ LC]

What am I looking for incase it jumped a tooth?

See the OTRAMM video below at 18:55. You'll need a 22mm socket for the crank pulley bolt.

 

[ramangain]

I'm still learning the details of the engine, but does each bank have a knock sensor? Check that. Buddy of mine parked his Sequoia at my place and a rodent chewed the knock sensor wire right through and made a nest in the engine bay. Symptoms were CEL (not diagnosed), poor performance, total lack of low RPM torque, and rough shifting at lower RPM. Best of luck

 

[Supergoji]

That's with crank pulley at zero.

This is one revolution of the crank.

Looks like she skipped a bit fellas.

 

[97 AZ LC]

You need to tear into it to see what went wrong. You're going to need a belt, a belt tensioner and two timing belt pulleys at a minimum.

 

[CorporalClegg]

unfortunate

 

[bigredmachine]

that looks like someone may have allowed the cam to rotate when installing the belt and didn't catch it. I doubt that the belt would have jumped that much with out some other obvious damage to the belt or some other component. id just retime it, set the belt and see what happens as it costs you nothing except your time. if it jumps again then new belt, tensioner and idlers just to be safe

 

[2001LC]

View attachment 2260389

That's with crank pulley at zero.

View attachment 2260393
This is one revolution of the crank.

Looks like she skipped a bit fellas.

Never mind, I see it now in first picture.

 

[97 AZ LC]

In the second picture the belt looks a little chewed up on the side.

 

[2001LC]

How did it run on first start after belt replaced?
Was tensioner replaced?
Did you check to see if pin was pulled from tensioner and the 2 bolts holding tight?

 

[Supergoji]

waiting for the parts to arrive.

 

[Supergoji]

both sides skipped, but only one had the misfire! belt done and now she's fine.

 

[97 AZ LC]

both sides skipped, but only one had the misfire! belt done and now she's fine.

What do you suppose caused the belt to jump? How many miles did it have on it?