chaseincats

@Yarb They're about a year old remanufactured Bosch OEM units, so we should be good on that front @Zed Head Fair point about the the clean injectors contributing to how it starts, but it's just odd that it used to start without that stumble before all of this. @Captain Obvious Trying to get back to that and figure out what the issue is @siteunseen Mine is the standard '78 distributor but I confirmed everything is in spec using the FSM (including the air gap between the reluctor wheel and pickup coil)

The skip noise it makes is normal? I don't remember it doing that in the past when I didn't use the CSV. Does your 280 do that?

It's the opposite where if I manually trigger the CSV it starts right up, but if I don't use it, it stumbles like it's not getting enough fuel

In the past when not using the CSV it hasn't done that skip/stumble noise it does now in the video at 0:16

I made a video of the hard start here which should help. It did start quicker yesterday (this video) but usually the skip at 0:16 lasts a lot longer. This is without manually triggering the CSV.

gotcha, fair enough

Gotcha, I'll keep using the switch to trigger it then. We'll see in the spring when it warms up if it's still feisty haha.

Regarding residual fuel pressure, it takes all night to get down to 15 or 20 and another day(ish) to get down to full zero. I tested the empty rail possibility when I still had the pressure gauge still on. I pulled the oil pressure switch connector, put the car in on, and once the fuel pressure said ~40ish I tried to start the car and there was no change to how it starts if I wait for a few days then crank it. Regarding the cold start valve, I jury-rigged a switch in the car so I can manually trigger it during cranking - when I turn that switch on, the car starts immediately (like it used to). But if that isn't used, it's a real struggle. I'm not sure if that information helps, but I figured it couldn't hurt to pass it along.

Gotcha - in this case, I'm trying to make sure the injectors aren't gunked up from the old gas. The more I sleep on this whole story the more it makes me question it. Maybe I'm wrong? The short story is: I put gas in the car in late October Had the issue where the old fuel hose blew on the freeway Let the car sit until a couple weeks ago The car had no power and ran lean Fuel pressure was perfect and no vacuum leaks after checking both Took the car out (and was running poorly like it had been - very down on power) Immediately got a few gallons of gas since it was almost empty After a minute or so, the car came back to life and the power returned Does gas really become less combustible that quickly? -chase

I actually haven't driven it again yet. The next drive would be to fill the tank but was waiting on a thumbs up or down on if the lucas injector cleaner bottle is safe to put in our cars. Any idea?

Update: No more losing fuel pressure as all of the connectors leaking fuel vapor are now tight and no longer leaking - still a mystery how the hoses either got all squished or all of the clamps backed out, but I suppose that's a mystery for another day. Regarding the hard starting - that is still there but maybe that will go away once I fill the tank? Thinking about putting a bottle of fuel injector cleaner in the tank after all of this. Does anyone have any thoughts or recommendations on products? For example, something like this.

Update: Cranking down the final injector clamp (ended up using a 1/4 inch socket with a u-joint, and an extension. The car doesn't smell anymore and the sniffer isn't picking anything up. I tested the device just to be sure by opening the fuel door and it smelled fumes by the gas cap (I didn't remove the locking gas cap). Looks like case closed 🙂 - thanks all!

Gotcha - thanks for the picture, I will keep the clamps at the top. A friend is bringing over the socket I don't have to tighten these and then we should be good to go - I'll check the carbon canister after that for sure. Regarding the sniffer, I pull the oil pressure switch plug and set the key to 'on' to pressurize the system. I then turn on the sniffer and move its bendable head to each spot with a rubber hose and clamp. It beeps and shows the concentration on the screen when it notices fuel vapors. The device is pretty impressive.

@Zed Head Where do you put your fuel injector's hose clamps on the fuel rail? Do you keep them closer to the injector near the bump on the rail's piping or at the top? I have my clamp on the top - since its further away from the bump, could it not be sealing vapors well enough?

The weird thing is this was the hose and clamps used on my remanufactured Bosch injectors: It also applied to my other hoses using the same style of clamps, I don't get it

Update: So that one I linked definitely worked (on the 'high' sensitivity setting) and taught me that my gas smell is actually coming from the engine bay, not the fuel pump area. It seems that ALL of my clamps weren't keeping the fuel vapor in the rail when pressurized. I cranked down all but injector #3's hose clamp almost to the max travel (because the injector #3's clamp screw sits right below the fuel pressure regulator so I'm going to have to think on how to get a screwdriver in there to tighten that one). It seemed to help somewhat - I don't understand how these clamps aren't holding even this tight - the injectors and hoses are all maybe a year or two old and using the proper injector clamps (not gates belt clamps). It also seems like all of the clamps slowly un-tightened themselves over the past few years because there's no way I had them this loose when I installed everything...

Will do - the sniffer should be delivered today

I'd have thought so too but I pressure tested the vapor tank and all of the hoses by putting the palm of my hand over the outlets and blowing into them - it was a dreadful experience but it did give me the answer that there aren't any leaks there.

@inline6 my 78's valve cover doesn't have a groove for an o-ring but impressive you were able to find one that works!

Fair enough - so all Z's have oil vapor stains on their valve covers?

I just don't understand how the pressure in the valve cover is so great that it is able to push oil vapor out of the cap. I checked my PCV valve the other day as well as the hose and everything is clear/working properly.

That makes sense - have you tried the gasoline sniffer I linked (or any)?

Update: so I tried to give it a start today and it definitely still put up a fight - but I'd say less so. My assumption is we'll be back to normal after I give it a full tank of gas to dilute the old stuff that's in there. Here's the plan - I'll keep you updated in the coming weeks: 1. take the car out again to confirm it wasn't a fluke 2. change the 3/8 hoses to 5/16 like its supposed to have 3. buy fuel stabilizer 4. fill the tank

I'm thinking theres a fuel vapor leak and its being pulled into the cabin in the same way as exhaust does with that vortex that forms in the back or via the firewall as my grommets are old. Either way its definitely a gasoline smell and not exhaust which is why I was curious about the gasoline vapor smell. My garage also smells like fuel when the car sits in there overnight. That said, if we're talking about cereal box gaskets, I'm more of a frosted mini-wheat guy and heres why - stick with me here - it's the only cereal where you're not hungry after about 30 minutes. That cereal has substance, I'm tellin ya, with sugar infused to make it palatable.

If I had to guess, you have your afm set 3 teeth leaner than the original setting since those are the numbers I got with 3 teeth lean (black gear turned clockwise) - my numbers are from leaning it by 2 teeth. If memory serves 3 teeth got me: idle: 14.2, cruise 15ish, WOT 13.1 Timing to get into cruise was set following the AtlanticZ TPS tutorial here I hope that helps!