r2doesinc

Exactly as the title states.

I just bought a '78 280z and its my first manual. I live in a college town and people like to cut you off and slam on their brakes for no reason, and im still getting the hang of clutching fast enough in those instances, and occasionally itll cause me to stall.

The problem then is that until I hear the fuel pump run again, the car wont start. As soon as I hear the fuel pump run, it starts on its first try. It usually takes me about 5 minutes of pulling the key out and turning it to run or whatever it is before i hear it run.

Is there something I can do to better force the pump to run? Does it sound like the fuel pump is on its way out? I was told that the fuel filter was recently changed, but he didnt have any info on the pump, so it could be quite old.

beg3yrs

I don't have much experience with FI systems (260Z guy myself) but I'm curious and also feeling bad you haven't got an answer yet.

I found this in the 280Z factory service manual: "If engine stalls for some reason, the air flow meter contact is turned OFF, and the fuel pump is stopped, though the ignition switch remains in the ON position. In this manner, fuel supply is cut off for safety purposes when the engine accidentally stops during driving." Unfortunately, it makes no mention on how to reset this condition. Maybe the Owner's Manual will tell you.

You can get your own copy of the FSM here: http://xenons30.com/files/FSM/1978%20280z%20FSM.zip

And here's an owner's manual: http://xenons30.com/files/Owners%20M...s%20Manual.pdf

Good luck!

r2doesinc

NA 280z here, but that quote sounds about right. Thanks for the infos.

rogerz

don't follow people so closely that you need to stop with the car in gear. made my son write an essay on that after he dinged my 83. and yes without the fuel pump running the car gets no fuel and will not run. could be a bad ignition switch or bad fuel pump relay. my guess from what you say is the ignition switch is worn out and does not properly send power to the fuel pump relay. new switch is availbable. Hope you didn't buy a car that might be older than you without sufficient wrench skills to repair same.

r2doesinc

It wasnt even that i was following super close behind, I just panicked a bit and didnt clutch fast enough. Just something I will have to get used to.

I wouldnt think that the ignition switch is bad as it starts up without issues in normal driving, its only after a stall that its problematic.

This is my second car, so im not a professional mechanic my any means. Im pretty smart and youtube is a hell of a teacher, but I also know when things are out of my league and have the pocketbook depth to have them handled at the shop.

beg3yrs

You might want to see if there's a mechanic who specializes in Z's. There may be a local Z club in town who can give you some recommendations. If you put your town in your "info", maybe someone on the forum will be able to give you some recommendations.

Don't take the rogerz post too hard. He is just trying to help and his advice is great. I too was wondering how much experience you have with at clutch. If it isn't much, good for you as manual transmissions are getting more rare as the automatics become more efficient and lower in cost.

Pay attention to those YouTube videos and make sure you have a good set of metric tools. These cars will keep you from being bored because when you're not driving them you are under them, leaning into the engine bay, washing them, diagnosing them and so on ...

Have fun with it.

rogerz

when you slam on the brakes everything wants to move forward. Is your battery tied down properly and your battery cables in good shape? How many times has this happened? Seems odd that you have to slam on your brakes so often that this is a problem. Is your negative cable grounded to the frame before going to the starter. Grounding thru the bell housing is not a very reliable connection.

Get your battery load tested. Be sure you have clean, tight corrosion free terminals on both ends of your battery cables. Be sure the ground (negative) cable goes to a bolt into the frame before going to the starter. grounding through the starter is not a reliable connection. Z's don't like low voltage. causes the electronics to act funny. it is possible to have enough amps to crank but not enough voltage to run the electronics. If you have one size fit all cheapo clamp on terminals they are a problem waiting to happen. Usually on a rainy night around Oh Dark Thirty.

LOw voltage will kill a Z every time.

beg3yrs

Driving home from dinner tonight, I got to thinking about your issue with not being able to start after stalling until the fuel pump comes on.

If you're running carburetors (N/A as you say), I don't really understand what's going on. Even with the electric fuel pump off, you should still have some fuel in the bowl to get things going again.

Then with Rogerz comments I also thought maybe the sudden stop has messed up your floats. That doesn't really make sense to me either as you have two floats that would have to be problematic at the same time. Think some more about what's happening, I don't think we're getting all the information - not saying you're withholding, just maybe something you don't think is important to the issue really is.

Just pondering - no conclusions here...

r2doesinc

Im getting there.

The car died thursday and the fuel pump wouldnt run no matter what. Pushed the bitch into the garage and have been going at it since.

Today I replaced the fuel filter, about 8 feet of fuel lines, the fuel pump, and the fuel pump relay, and added a fuel pressure gauge.

After the hose, filters, and pump, the car still wouldnt start. No fuel pump sound. Ok. Progress is still progress.

Disconnected the fuel pump relay and hooked it up to the ac relay instead, fuel pump came on instantly. Ok, bad relay. Drive hour and a half and get a new one. (this one BWD R800 - Relay - Multi-Use | O'Reilly Auto Parts) This one has a different pin configuration that I havent been able to find a diagram for, and I wasnt able to figure out the mapping correctly.

Car was running with the fuel pump connected to the ac relay, so I thought Id go out and met some friends. When I go to leave, car wont start. I hear the relay clicking under the hood, pump going on and off with the clicking. Check my fuel pressure and im steady around 35 or so. Car still wont start.

Issues as I currently see them
1. Bad relays. Brand new on is in the car, but I cant get it hooked up correctly.
2. Even with fuel pressure where it needs to be, car still isnt starting now. Its trying to, but it just wont catch.

Also, Ill probably put another post together about this one specifically as its unrelated to my fuel delivery issues, but I think I have a clutch issue, and as this is my first manual vehicle, its not something I have been able to figure out.


At high rpms, sometimes I hear this TERRIBLE grinding and smell burning clutch, accompanied by what feels to be a downshift almost, the engine gets super loud like its under heavy load, and the car kinda shudders and slows a bit.

I wont lie, I probably destroyed the clutch the first few days that I got it and was learning to drive it, but I wanted some opinions on it before I take it to a shop to have it looked at. Is there any self diagnostics I can do there? I see some tests like the ones mentioned Clutch Drag Kills Synchros! – Jacks Transmissions, but I will have to get it running again before I can try.

r2doesinc

I dont have to slam them very often, that was just the case on the specific day I wrote the post. I live in a college town and got cut off. I panicked a bit - new manual driver - didnt clutch and bang, dead.

The battery is secured pretty well, and my volts are reading as ok from the gauge in the dash.

Now that Im thinking about it though....a few minutes before the car finally died on thursday, the radio went out and wouldnt come back on. Fast forward a few moments and the car died - no stall. Battery looks, not new...but clean and in good condition.

Also, the tach died. Thats now working again.

This car is quirky man.

beg3yrs

What kind of carbs are you running? You say pressure is 35? Is that psi? I'm hoping that was a typo as SU carbs take only about 3 to 5 psi. If you're running 35 psi on an SU carb you're probably flooding things out.

Yes, it does sound like your clutch is gone.

r2doesinc

78 Z came with Fuel Injection, so 35ish psi is good.



When you mentioned FI before, I was thinking "forced induction", and NA as "naturally aspirated". Im coming from the 350z, so carbed or not is not something I usually think about, sorry for the terminology confusion.

r2doesinc

The clutch is not a part I am very familiar with, which part sounds like its going out? Where would you recommend I start poking around?

r2doesinc

After dying in the parking lot next to the mechanics last night - and not starting for the half hour or so that i tried before i got a ride - I called them to have them check it out. Went there to try and get the car from its current lot to theirs, and it started right up, no relay clicking, just perfect startup.

They are looking over all the electrical stuff. Checking all my relays and wiring. Electrical is not a field I feel comfortable mucking about in, so im calling in the pros to go over everything Ive done and take it from there.

Once the starting issue is resolved, onto the clutch. And i still need to get this AC stuff worked out soon too. Shes certainly a project car, thats for sure lol

beg3yrs

OK, we're on the same page of definitions now. I was the one using NA incorrectly.

My own clutch knowledge is all self-taught so it could be full of errors, especially in terminology. The ones in the Z's aren't all that complicated. Take a look in the FSM and you should get it pretty quick.

The smell is likely from the friction disk slipping. This could be because the disk is just worn down so it won't grip any more. It is a normal thing for this to happen as the concept is like that of a brake system where the pads or shoes rub on metal and eventually wear out and have to be replaced. As in brakes, even worse things happen if you don't attend to this quickly.

We can talk AC (air conditioning) a little bit. I'm half-way through updating the system in my project restoration. I've decided to go with a complete under-hood upgrade ($800 on eBay) which replaces everything there. You get a more efficient parallel flow condenser, a rotary compressor, a new receiver/dryer unit, a bracket and hoses. You keep the evaporator unit already in your car. I took my evaporator to a full-service radiator shop and had it compression checked. They found a small leak and were able to fix that for $40. Not bad as new evaporators are in the $200 to $300 range. Just something to think about.

r2doesinc

Update on the fuel delivery front.

The engine is flooding. The injectors are not turning off when they reach pressure. The mechs are looking over all the wiring and will probably have the car for a few days

As for the ac, i have a whole list of stuff to replace, evap, drier, blend door, and they recommend the retrofit kit. Thankfully since winter is coming up its not going to be too bad, but I actually dont know the state of my heater - 98% sure thatd also be busted - so it may be a bit more important than i had previously thought.

beg3yrs

That's good news there is progress on the performance side.

Heater is pretty simple. You can pull the core and its mechanism yourself and get it tested at a radiator shop. I had two cores tested. Both had leaks but one was repairable. $80 and I was done - yay. If you must, cores can be found on eBay and probably other places, like junk yards.

Steve260Z74

A few days? I would guess that the mechanics are not Datsun guys and do not know of the Nissan Fuel Injection Manual (available on XenonS130 - S130 Reference) or are too stupid to RTFM or are too busy to care about your car.

The pulse on the fuel injection is a sinking signal through the ECU. (In lay terms, there is always 12VDC+ at the injector. The negative side of the circuit is completed through the ECU.) It would take me 10 minutes to see if there is a voltage drop across the injector, and most of that time would be to get my meter out of the case. The exception would be if someone jacked with the fuel injection wiring. Does it have an aftermarket system in it?

After you rule out the ECU or cross-connection, the next thing is the mechanical connection of the injectors.

r2doesinc

I sent them the FSM link, but they didnt start poking around till late saturday and they close early on saturday too. Sunday was closed, so Im expecting to hear something today or tomorrow, an few days from the original drop off :P

Pretty much everything seems to be stock on the car. Ill be calling them when I get out of work today and will mention what youve said and get back.

r2doesinc

Update.

ECU is bad.

Anyone know a place to get a cheap replacement?

My fallback is always thezstore. I see http://www.thezstore.com/page/TZS/PROD/11-3031 which isnt too terribly expensive.

Also I see some stuff from
http://www.partsgeek.com/catalog/197...trol_unit.html

Much cheaper there. Any suggestions?


Cardone sells them directly on amazon, just got one and will be here 3-5 days. Will update you guys on the progesss when that happens.