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Discussion Starter #1
Hi everyone, this isn't another 'how do I superpower my e16' thread.. but I just got an 87 Sentra with a recent Weber swap and have a few questions..

First, I'm not sure everything was done correctly, as I immediately found that the detent cable to the transmission was not connected to the carb in any way.
I notice a Weber swap seems to usually be done along with a distributor swap to an 83 model; is this important?
Is my ECU likely doing a poor job of advancing timing, since half the environmental stuff has been removed?

Secondly, my tachometer isn't working; it sits at zero and then finally kicks in at around 5k and seems mostly accurate at that point, then flops right back to zero below 5k.. is the tach controlled by the ECU in any way?

Thirdly I have the 3speed auto transmission and after about 70mph, I'm in 3rd and the engine is doing a solid 5k+.. is this transmission supposed to have an overdrive gear also? and is this transmission controlled by the ECU in any way?

Lastly I have a variety of half connected hoses from the Weber swap and I'm wondering what all can be fully removed.. Thanks for any helpful answers!
 

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The 3-speed trans is mechanical and not controlled by the ECM; it does not have an overdrive. Not having the detent cable connect affects the shifting properties of the trans, so it should be re-connected. An '83 or earlier distributor has a vacuum advance which can be hooked up to the carb to control the ignition timing advance. Most of the time the ECM gets disabled in the Weber swap. I really can't tell you what hoses can be removed without seeing which ones they are. Personally, I'm not a big fan of the Weber swap. The factory Hitachi carb is actually a pretty good carb for this engine.
 

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Discussion Starter #3
Thank you smj999smj.. that answered some of my questions.. I think my transmission is in good shape, I did connect the detent and, while it probably needs adjustment, it is doing what I would expect.. I was just surprised at such a low top speed, especially since the engine seems to be running really well and snappy.. does this sound normal for this car?. there are a few pics of my engine in my 'garage' if you'd like to take a look..
 

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@xbj9000 where do you get - or where are you going to get - your VCM air filters? The metal cylindrical filter can next to the ws wash reservoir (in your garage pics)?

The tach signal comes from the power transistor (at the coil) to the IC. There should be a resistor between the PT and the IC (for the tach). The resistor should sit next to the battery (downward and behind the d's headlamp assy). Perhaps 2.2k ohms.

Also see/search Gallery: 87 E16S.

We should park our cars next to each other next time I'm in the N'ville/Smyrna area.
 

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Discussion Starter #5
car guy.. I have no idea lol, I've only had the car a week.. thanks for the tach info, would a bad resistor explain my tach behavior?. I have a multimeter so I'll check that soon..
 

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Well, there's just the resistor and the wire run to the IC and the PCB there and the tach there. So, it can only be a couple of things. Resistor could explain things if its in and out, but I'm thinking the issue is the IC tach itself or possibly the PCB (connection). Sometimes on these cars, when the IC warms up (especially with the bulbs on), signals improve.

Are the fuel gauge and temp gauge working? They have a Vreg in the IC. Would have to look-up (refresh memory) if the tach goes through that also.

Hey, if you ever track down your VCM air filters, PLEASE let me know where! Thanks.
 

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Discussion Starter #7
yeah, fuel gauge works (although he said 1/4 full is actually empty so I haven't let it get much below half), and temp gauge works and is accurate.. all the little dummy lights seem to work also, and the dimmer..
 

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Discussion Starter #8
also, I don't think the VCM is even in play on my car, with the weber swap and all.. right?.
 

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First thought that, but your image 3 shows the VCM with the hoses to it (from the air filter assy), AND also shows a hose leading to the vacuum gallery (which would be normal). Normally, the hose routed (along the back of the VC, via the vacuum gallery, all the way around) to the back side of the IM (back up under the EGR valve) where there was a dedicated port for it (for the vacuum pull). Then, another of the VCM's hoses went to the ISCV. Your ISCV is gone with the Weber, but the rest seems to be there.

You'll have to let us know if the VCM is or is not functional (connected to IM vacuum and connected/helping with idle control). Especially cold-idle control. The VCM wasn't usually involved once warm-up occurred. Throttle adjust screw and dash pot were. The vacuum motor for cold-start and warm-up also is missing on the car (wouldn't have been needed once the Weber went in).

How many miles on the car?

What trans and gears?

Oh, and on your timing question, it was done using CTS, BPS (which is still on the car under the ws wiper motor), IAT, and optical sensor in the dizzy (1' and 180' separate signals) with control then of the power transistor.

What is the Nissan # stamped onto your dizzy (should be in the format of xxxxx-xxxxx)?

And what are the additional code letters and #s on the dizzy (also stamped)?

And, what are the first 3 letters of the VIN - Japan or Smyrna built?

And, what is the production month/year on the door jamb?
 

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Discussion Starter #10
well, all of those modules have at least one hose disconnected.. I'll make some clearer pics tomorrow, and get those numbers.. it has just under 126k miles.. the transmission is the 3speed auto, RL3F01A..
 

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Discussion Starter #11
some more pics:




^ these are totally disconnected from vacuum..



^ here you can see a few open hoses..



^ circled here is a tee with a small 1" hose which is open..



^ the hose circled here is about a foot long, and not connected to anything..



^ another view of some open hoses..


apparently I forgot to take a pic of the VCM, but the lower middle hose on it is not connected to anything either..
 

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Great pics!

The first pic is the redundant pair of vacuum switches that mated with the vacuum cut solenoid that should be underneath the egr/carbon canister solenoid that is disconnected in the next-to-last pic. Nissan did away with the redundancy (the pair of vacuum switches proved to be overkill). The vacuum switches and vacuum cut sol destroyed vacuum to the ISCV in fail safe mode (if the car/engine was in a catastrophic accident - preventing the engine from continuing to run). So, it makes sense these are gone with the Weber because the Weber did not use the ISCV.

The second pic circles all went to the ISCV which is no more (due to the Weber).

Also, in the second pic, the AIV solenoid (under and in between the circle marks) would no longer be used since air injection baffling (on the air cleaner) is gone.

The third pic is the BPS. Surprised (somewhat) that is not on any IM vacuum port, as the ECU uses it for ign control (timing). Having said that, at sea-levels (as least), the E16Ss would start and run with the BPS disconnected. Also, the red end of the small circular plastic "vacuum delay" just upstream of the BPS is pointed the incorrect direction. The red end should point to the BPS. And, also, there was a HIDDEN embedded orifice in the hose just before the vacuum delay. Probably wise to hold onto that orifice if it is still inside the hose (just in case ever needed for the BPS). In other words, if ever replacing that hose (to the vacuum delay), don't assume it's just "an empty" standard vacuum hose. It's not.

Next-to-last pic is the egr/carbon canister solenoid. Since that is disconnected, the BPT valve (to the left of the egr valve, in the second pic), will never be commanded by the ECU to open and therefore there will be no egr "lift assist." That would cause idling issues at times. And, no emission vapors will flow from the gas tank nor vapor canister into what should be an "EPC valve" on the back driver's side of the IM. The EPC valve looked similar to the PCV.

Last pic, in between the 2 circles drawn, the PCV valve has been relocated - IF the Weber end is a PCV at all (and not just a port).

Thanks for the time and effort to post the pics. Great seeing them.

Now on the dizzy #. That WAS the 87 dizzy - both # sets you provided. So, they did NOT swap in an earlier dizzy. And, the dizzy E was one of the latest configurations.

This raises an interesting question: given the dual vacuum switches but the latest dizzy, what are the 6th-through 4th-to-last digits (#s) of the VIN? And, was the VIN Japan or USA? Still would be neat knowing the production month and year.

It's going to be fun working on the car. Would love to be on it ...
 

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Discussion Starter #15
the weber is the usual 32/36.. I applied suction to the BPS and there was a change in idle.. should I connect this to the carb somewhere?. I also noticed this:


^ back side of carb, open vacuum port??
 

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<should I connect this to the carb somewhere?. I also noticed this:>

The BPS originally connected via the T to the front most of two ports on the pass's side of IM (rear), where the rear most (firewall side) port was the vacuum hose to the AB valve. Since your AB valve is still there, following its vacuum hose should lead to the front most BPS T vacuum IM port.

I would first check RPMs on #1 spark plug wire while concomitantly confirming timing at the crankshaft. Then, I would re-check both again after connecting up the BPS to its "measured" vacuum.

Original engine specs were 800 RPM at idle with 7' BTDC. Not sure what the Weber would be idle-RPM-wise.

Hard to see if the extra port in the pic is vacuum or ported vacuum.

Can you tell if the original mixture heater sits under the Weber on top of the IM opening? It was a 2-pin connector: 1 pin vertical and 1 pin horizontal.

Its relay should be in the pass's side relay box - far right inside the 5-relay box (immediately to the left of the VCM air filter).

How'd you come by the car?
 

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Discussion Starter #17
I don't see anything between carb and IM besides the two adapter plates.. I'm sure I'm about to do the distributor swap so I guess it doesn't matter, but I was curious if I could improve it any in the meantime.. I'm really enjoying this car, and I have more of an old small block chevy background so, to me less is more and I'd just as soon not have a computer involved.. I also have an '87.5 Audi Coupe GT, it's way cool but extremely confusing to me lol..

I ended up with this Sentra after my very awful daily driver (chevy tracker) got totalled and I needed something cheap asap.. lucky me I found something cheap and fun.. :) apparently the guy I got it from took a loss after having a lot of work done, he had wanted to fix it up but I guess was going too over budget..
 

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That's cool you got the car. Nothing like having 2 87's in the stable now.

The E16S camshaft end uses an "offset tab" for mating with the 2 offset half-moons of the dizzy. Not sure what config the 83 dizzy uses nor if its connector will be the same 4-pin "harness" "plug-in." That plug-in can be difficult to get unplugged from the distributor, without breaking the grommet or connector itself (usually brittle white plastic). There is no rigid part to grasp onto to ease out the plug-in, unlike nearly all other connectors. It plugs "inside" the dizzy. Sometimes it is easier to disassemble the dizzy to free out the plug-in the other direction (pulling out the optical sensor from the distributor while the plug-in remains screwed into the back of the distributor, for counter resistance).

IF you remove the 87's 36A02 dizzy and happen to remove the rotor and metal plate underneath it (2 side screws hold the plate sides into place) and happen to remove the center shaft screw, let me know which "RSB" # the old dizzy optical sensor has on top. Could be RSB-06 or RSB-03 or 1 of 2 other #s . The optical sensor itself is held in with 3 phillips screws.

The 83 dizzy might be an RSB-03 optical sensor config - with 3 diode pairings - whereas the RSB-06 would be a dual-diode pairings config. The other 2 possibilities could be either config.

If it's an RSB-03, shine a high lumens light in on the small upper and lower metal "plates" to see if there are "slit readers" on the far left side, middle, and far right side.

If it's an RSB-06, see if there are only middle and far right slit readers.

One last recommendation: IF disassembling the dizzy(s), put a small scribe mark on the top of the 360' reluctor slit plate BEFORE gently easing it out - which is best done with the two small "raised alignment tabs" facing outward/away from the optical diode housing. That way, the reluctor plate will not be damaged or bent. And, the scribe mark will prevent installing the reluctor plate 180' backwards of firing order.
 

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Discussion Starter #20
right, it seems like that's the thing to do as far as I can tell.. it doesn't seem like anyone uses the weber in combo with the newer distributor..
 
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