Is My Timing Off?

[peejay]

Can't seem to get this darn thing running right, so thought I'd recheck my timing belt install, does anything look off here?

 

(I know that the "straight" line marks on the belt aren't lined up with the camshaft sprocket dimples).

 

Next step is leak-down test if everything here checks out.

 

[Slartibartfast]

I think you're a tooth off between the cams. Should be 40 belt teeth between the cam sprocket dimples. I think I'm seeing 39. (Tough to tell, though--that lower right pic doesn't quite show the driver's side dimple.) Verify 43 belt teeth between the driver's side cam dimple and the crank dimple while you're at it. Don't worry if this puts the sprocket dimples a little off from the marks on the cover. Mine didn't quite line up either. The tooth count has the final say. I suspect a disagreement between the two led to that second white line drawn on the belt, and the belt being a tooth off, and the engine running poorly.

 

I see the fasteners that hold the rear timing cover to the intake are missing. Do the holes for those not line up? The VG30 intake gaskets are much thicker than the stamped steel VG33 intake gaskets, so if you use the wrong ones, a lot of stuff doesn't line up properly, including those holes. I found this out the hard way on mine when Rockauto sold me the wrong parts. Mr. 510 also ran into this issue on his VG34 build, so even if it's going on a VG33, the VG30 intake still needs the VG30 gaskets.

[peejay]

Thanks, Slart!

 

Realized some of the sprocket was cut off after I uploaded, sorry about that, how's this:

 

 

As for those missing bolts, I thought those mounting holes where "shared" by the cover bolts, but I could be wrong, about that, too!

 

 

And for the gaskets, I thought I used the VG30 ones, but I'll double-check that, too, could be the source of a vacuum leak.

[Slartibartfast]

Good, there's that ruled out then. Might still be worth checking cam to crank on the off chance. Looks like you're right about the bolts too. Been a minute since I did mine! If the hole lines up, and it looks like it does, I'd say you used the right gaskets.

 

I don't see anything else weird in the pictures. Cam sprockets are on the right way around. I don't remember exactly where my rotor was pointing, but I remember trying it a tooth one way and then moving it back before I was happy with it. If it's pointing to where #1 is supposed to be on the cap, it should be good. I'm assuming you've checked ignition timing.

 

How weird is it running? And what all has happened since it ran right?

[peejay]

Well...how much time ya got?

 

Okay, the truck was my daily driver until it wasn't, it got relegated to weekend warrior around 2016. And one day I went to drive it and got the code 51 for injector circuit. I checked the resistance of the injectors, if I recall 4/6 were bad, so I replaced them all. And by replaced, I mean, bought them in 2021, and finally got them installed and test-fired the vehicle in 2024! So yeah, it sat all that time, and not sure what harm that did.

 

When it did fire up, it would idle rough, was hard to keep running. Oh, and the water pump bearing had gone out/was squealing, so I figured I'd change that and replace the timing belt while in there. Did that, still the rough idle. I figured now was a good time to change the oil, and when I did, it reeked of fuel. Uh-oh...My fear was (and still is) that all that sitting somehow the rings got stuck. But the smoke that it produced was more black/grey than blue.

 

And that's where I am today. I can barely keep it running without feathering the pedal to even check the ignition timing. When I got even close, it looked like it was retarded, but you know these distributors have a small range of adjustment, so I figured if the timing couldn't be corrected with the distributor, then the cam timing must be off, hence me pulling that and rechecking.

 

It passes all of the diagnostic mode checks.

 

The only "aha, there's your problem!" is when I was doing the timing belt, the passenger's side cam gear jumped ahead on me and few (maybe 6-8?) teeth, and I thought, "uh-oh, some valves maybe hit the pistons and got bent", but that could be my paranoia, or, yes, that can happen even in a non-running engine?

 

I figured the leak down test (which I am NOT looking forward to, looking at you, No. 6 cylinder), would reveal if something is wrong internally with the engine.

[peejay]

Okay, I don't remember ever pulling the distributor since I had the thing running a dog's age ago, but I recentered it within the adjustment bolt, and looking at this pic, looks like it could be a tooth off? So I'll pull it and try to better align it with that imaginary green line, can't hurt, right?

 

Edited February 25 by peejay

[adamzan]

On mine the distributor was kind of effed up in the sense that you could turn the rotor with some force and further adjust the timing. It happened after a t-belt change and It must have been whacked. But it didn't stall. But moving it a tooth will move it way past the normal range.

[peejay]

That's what I'm afraid of, adamzan, that moving it "one tooth" is just gonna throw it off on the other side of the mark, leaving me "back" where I started. Maybe the old timing belt jumped, which I don't think it did. Will report back my findings, thanks all!

 

Edit: Nope...one tooth ahead was pointing way off, I think it's correct where it is, sadly. On to the leak-down test!

Edited February 25 by peejay

[Slartibartfast]

So it sat, an injector failed, you replaced the injectors, and it hasn't been right since.

 

I'm suspicious of the new injectors. If one or more are dumping fuel, that would explain the diluted oil (runs past the rings), the rough idle (because the flooded cylinders aren't contributing much), and the smoke. I'm also remembering the issues Cuong had with a set of cheap injectors a while ago.

 

And how old is the gas it's trying to run on? If it's the same gas that's been in there since '21 (or before?), pull a fuel sample.

 

Don't worry about the cam jump. Mine did that too. No harm done, apart from making me nervous. If you'd kept spinning it around, found a hard spot, and forced it past that hard spot with a breaker bar, then yeah, that would be a problem. But if it just jumped, and you rolled it back the way it came, then no, that shouldn't have hurt anything.

 

I had a similar head scratcher with the distributor when I put mine back in. There were two spots that were close, but both seemed like they were half a tooth off. In the end I just picked one. I had enough room from there to adjust the timing to the spec'd 15 degrees. If that hadn't worked, I would've restabbed it to the other position and tried again.

Edited February 26 by Slartibartfast

[peejay]

Logic, eh, Slart? Ok, I will play your game!

 

Thanks for mentioning @Cuong Nguyen, I did not heed the warnings and I did purchase those very injectors that were cautioned against. Now, at the time, they ohmed out correctly, were installed, and the injector (51) code went away, so I assumed all was well! And it looks like the only way to get injectors now is pay out the nose (AutoZone), or send them off to be rebuilt?

 

***

Now, indulge me in this game! Let's pretend I just bought this vehicle/it was given to me as, "I dunno, it was running, now it won't idle and it's got black smoke, but it's yours" (hmmm, might be precursor to a listing of my own!).

 

So it's showing no codes, but not running right, and somehow this forum (and the FSM) led me to "have you checked the injectors"? And then I check them, and the resistance is within spec (haven't checked that again yet, it's on the list), and they pass the rotate the distributor and hear them fire test (also gonna do this), and the fuel pump/pressure regulator show as ok (i did do this, and the numbers are correct and it holds pressure, which should rule out leaking injectors?)...anyhoo, if "the new owner" did all these injector checks and they passed, could they still be bad? maybe they only show as bad when running? and how would i check that?

 

Thanks for playing! As much as I'd hate to pull these injectors again, I'd much rather that than an engine rebuild!

 

***

Edit #2: @SlartibartfastYou may've just opened a whole new can of worms! Now I'm looking at doing the "Z31 Late Model Injector Swap". The kits look promising, but what could potentially be even better is, the rail I pulled from the VG33 may be a drop-in on the VG30 intake manifold. In which case then I may only need the Bosch EV1 to EV6 adapters, which I've ordered! Stay "tuned"!

 

(And back to the "bad" injectors, I'm thinking they could pass all the electrical tests, but if they are cheap knock-offs, the flow characteristics may be WAY off, so the ECM is doing its job, but its relaying the info to injectors that possibly have the wrong "profile", like the nozzle pattern could be "Full" as opposed to "Cone", in water hose nozzle parlance!

Edited February 26 by peejay

[Slartibartfast]

There's a special tool for testing injectors. It's basically a fuel rail to feed the injectors, a circuit to drive the injectors, and a row of graduated cylinders for the injectors to spray into. The machine pulses the injectors, and the cylinders collect the fuel. While they're pulsing, you can confirm that the spray pattern looks good (nothing obviously clogged or dripping). When they stop, you look at how much fuel has collected in the cylinders. If you know what the injectors' flow rate should be, and you know how long they were open during the test, then you have your spec to check them against.

 

Without that special tool, you could still check the flow rates against each other, but this would only tell you if they're consistent, not if they're correct. I guess you could swap one known good factory injector in place of one of the new ones and run the test again.

 

Have you checked the spark plugs? Are all six spark plugs black or gas-soaked? If they all look rich, then either all of the injectors are wrong (which would make sense if the flow rate on your new set is incorrect), or a bad sensor reading is making the computer inject that much fuel on purpose (likely coolant temp). If only some of the plugs are rich, that suggests you've got bad injectors on those particular cylinders.

 

The OE injectors have colored dots on them. I do not know what changed between the various colors, but it sounds like some of them may have different flow rates. I think blue dot and black dot are just different spray patterns, because some previous mechanic replaced one of mine with the wrong color, and it doesn't seem to care. But, yeah, ideally you want a matched set.

 

My VG33 (which was previously swapped into another WD21, so it has the VG30 intake) has VG33 injectors in it. Different electrical connectors, but the same flow rate AFAIK. Not sure if that's the same thing you're looking at with the Z car injectors. But if you've got the injectors that the VG33 came with, I'd give those a shot.

 

I haven't had to source an injector yet, so I'm no help there. I think @gamellott replaced one recently.

[peejay]

Is that tool for testing the injectors probably out of the scope for the DIY shadetree mechanic? I've seen some in pro setups testing these cheap injectors (shoulda known better, I paid $70 for a set of 6, when I probably should've expected to pay that per injector). I might keep these cheapies around just for test purposes down the road. (I've become fascinated with googling "cheap injectors" and all the comments are the same: avoid, could cost thousands of dollars in the end, etc.)

 

All plugs (I'm just gonna guess on #6!) were definitely fouled and sooty. When I removed one plug, you could still see fuel vapor billowing from the hole, for SEVERAL seconds. Guess it's good I came to my senses before hydrolocking the darn thing?

 

I mentioned that Z31 conversion, because when I googled "nissan injector upgrade" or something like that, Z cars were the only thing that came up. Looks like the Z cars use injectors with a longer pintle. The VG30 and VG33 "truck" injectors look identical to me, except the change from the Bosch EV1 connector to the PROPRIETARY Nissan connector.

 

I just got the upper plenum off, once I get the rail removed, I'm gonna see if they will simply swap over (the donor engine is a '00 Pathfinder). And CZP makes adapter harnesses with Bosch EV1 on one end and Nissan PROPRIETARY (can you tell that annoys me?) on the other. Was gonna try and make my own, but de-pinning that PROPRIETARY (last time, I promise) Nissan connector looks like a nightmare.

 

Will follow-up as I progress!

[peejay]

The rails...

 

 

I'll get up the nerve tomorrow to see if the VG33 will drop right in (or does someone already know if it will/won't?). If not, I'll begin the annoying task of removing the VG33 injectors and putting them in the VG30 rails.

 

(Edit: holes in rail mounting ears look larger on the VG30...)

Edited February 27 by peejay

[gamellott]

OOOOooooooof... This is a Novel!! And a bit above my head on the technical aspects of it. As far as the injectors go, sourcing, I had to replace 2 of them on my VG30 not tooooo long ago. Maybe it's been a couple of years now... maybe... I replaced them with the Beck-Arnley version of them. Found them on Rock Auto. I don't recall how many they had, but I only got the 2 that I needed at the time. 

 

I looked not too long ago to get the remaining 4 done, but finding NEW was becoming unobtainium. I wound up getting 2 Standard Motor, and 2 Rebuilt ones that I haven't found the need to install yet. The 2 good "New" brands that I would stick with are Standard Motor Products and Beck-Arnley. Beck usually re-boxes OE stuff, or that's what they did in the past. For imports, they're pretty solid. Standard is usually pretty solid as well. If you punch the part numbers into Amazon, you might be able to find them there as well and not get gigged for shipping like Rock Auto. I would always buy new if you can avoid the rebuilt ones. I have no real experience with rebuilt ones aside from 2 that I got off of Rock that have not been installed. With the age of these, you get what you can get I suppose.

 

BTW, the 2 injectors that I replaced made a world of difference in the idle and perceived power. I have some steep hills that I don't lose power on anymore that I used to before the swap. Upgrading the injectors might not be a bad idea, but if the rest of the engine is stock, you're probably better off keeping it stock.... but don't go the cheapest route. That doesn't always work out in your favor.

[gamellott]

As far as timing goes, here's my lesson learned....

 

One time in band camp... I disassembled the front pulley from the harmonic balancer thinking I would clean it up, paint it, whatever the reason... without properly match marking it. When I reassembled it, it was off by one bolt hole... silly me... still ran, but ran like crap. Didn't get the timing set properly until I properly clocked the front pulley. Don't do what I did... 

[peejay]

Apologies for the novel, I tried to make it more of a novella!

 

I did see that RockAuto carries the VG33 injectors (Beck-Arnley), well, they had 5 left as of yesterday, but yeah, VG30 is unobtainium. The VG33 ones I have ohmed out ok (12.0), but they've just been sitting in my parts pile, so can't hurt. Waiting on my J.I.S. bits to come in, or may order some Vessel screwdrivers,won't be reusing that hardware but wanna see if it makes a difference, using a phillips on the screws gave me fits last go-round.

 

I had timing issues on a 16V VW many years ago, and how it ran reminded me of this Pathfinder, but off by one tooth was not to be. I'm gonna try and get a borescope down the cylinders before I button it back up to see if there's any fuel hanging out in there.

[Slartibartfast]

At least it's not a telenovela. I don't remember enough Spanish to deal with that.

 

13 hours ago, peejay said:

Is that tool for testing the injectors probably out of the scope for the DIY shadetree mechanic?

 

I'd be surprised if an actual repair shop had one! A speed shop might. Seems like it would be easy enough to build one, but that's probably overkill just to laugh at an $11.67 injector pissing gas like the Sprite nozzle on a soda fountain.

 

You might be able to redneck it, similar to one of the tests you suggested above--turning the distributor to make the injectors fire--but with the fuel rail propped up, out of the intake, with cups under it to catch the fuel. You wouldn't be able to check that the flow rate was correct, but you would be able to see if it's the same on all six, and check the spray pattern. Make damn sure the coil is unplugged from the harness if you attempt this test!

 

IIRC the injectors fire in batch rather than sequential during startup, so don't be surprised if all six spray at once.

 

Speaking of redneck, I saw a Hoonigan video a while back where they cleaned an injector with carb cleaner, a tire valve stem, and a 9v battery. Something to keep in your back pocket in case you find a stuck one or a bad flow pattern.

 

Any fuel that was down the cylinders has probably either evaporated or run past the rings into the crankcase by now. Doesn't hurt to make sure, though.

 

And yes, proper JIS drivers are a thing of beauty and a joy to behold.

[Slartibartfast]

9 hours ago, gamellott said:

still ran, but ran like crap.

 

I'm impressed it ran at all at 60* out!

[adamzan]

I've replaced some of the injectors on mine with new bosch ones but since they're hard to get now, I just pulled used ones off my parts truck that checked out OK.

 

Also when you're doing the timing make sure you are following the procedure with disconnecting the plug and the rev up procedure they have in the FSM. Like others have said if you or someone has separated the balancer from the pulley (the six small bolts) it's possible and likely it wasn't put back on right. Set the engine at TDC for #1 cylinder and see if it the timing mark on the cover points at the 1st mark on the pulley. It'll be pretty obvious if it isn't right.

Edited February 28 by adamzan

[peejay]

Well, yay and GRRRRRRR at the same time...

 

Tested the VG33 rail, and everything lines up:

 

 

However, I lost the #3 cushion in the process:

 

 

This makes the 3rd or 4th one I've lost! Guess that's one way Nissan makes sure you use new cushions!

 

Gotta order the connector adapters anyway, so back to the waiting game.

 

***

Edit: Finally some good luck! Found a lone cushion in a box of non-car part stuff! That'll teach my wife to encourage my inability to throw things away!

 

(Ok, Slart, so I really wanna try those J.I.S. bits out, but looks like I may not have to (yet), plus they are probably coming from the mainland, so who knows how long that'll be, I was too cheap to order a set of Vessels right now...and I like some of the injector testing methods you described. With these cheapies, who knows if it's a flow thing, or pintle not seating properly, etc. And I did peer at least into the intake runners to see if the cushion found it's way in there, got a so-so look at the top of the valves, nothing to write home about).

Edited February 28 by peejay

[gamellott]

Those cushions come in a seal kit. When I rebuilt the top end, I bought injector seal kits and only replaced that part of the fuel system. I do NOT know what/if they're interchangeable with the VG33 though.

[gamellott]

Idle curiosity... get it???

 

Is there a difference aside from the connector between the VG30 and 33 injectors? Sorry if this was covered in previous conversations, TLDR.

Edited March 1 by gamellott
clarification

[peejay]

You should be pun-ished for that one...

 

I believe the injectors are identical, other than the connector, so once the VG30 supplies completely dry up, the VG33 should be a viable option, other than having to get/make adapters, splice.

 

(I didn't remove any of the VG33 injectors to compare, but the rails, caps, hardware...everything looks nearly identical.)

[gamellott]

Thanks @peejay

 

More for when I might ever swap over to a VG33 block. If I ever make the time to do such an upgrade. All of this stuff is becoming unobtanium as time goes by.

[adamzan]

Any updates?