Starting Issues with my 1983 RoW 3.0

[Sirius Driver]

So I've pretty much have gotten its pattern down.
8:00 a.m. -Cold Start- Takes a few turns of the crank and it start rights up. I drive.
8:20 a.m. -I pull over and get a small cup of coffee.
8:25 a.m. -Get back in the car and it starts right up.
8:55 a.m. -Pull into Garage and get to work.
12:30pm. -Go to start car and it just cranks. At times it does want to start but the engine will not catch unless I depress the gas pedal. When it catches, it feels like its not firing on all cylinders and I have to gas it to kinda get em all going and smoothly. I replaced the Cap and Rotor and I dont think I experienced much of the missing cylinders when I reved it up to achieve a solid rev with all cylinders firing. The cycle then continues. It will pretty much do this if it sits longer than 25mins after being driven. What do you guys think I should look at? My mechanic mentioned a fuel valve that might be allowing the residual fuel to leak back into the tank causing me the starting issue. My question is why does it always start right up when cold in the mornings? I could sure use some insight. Thanks!

[Gogar]

There's two things:

1. The fuel pump "check valve", which is at the outlet of the fuel pump, on the steering crossmember under your feet.
2. The "fuel Accumulator", which is right before the fuel filter on the left side of the engine bay.

Both of these things perform a similar function, to keep pressure in the fuel lines after the car has been turned off.

When one or the other or both go bad, the fuel in the lines is allowed to lose pressure, at which time it will 'boil' or turn into vapor, etc.

When you come back to start, there's air in your fuel lines, instead of gas, making it harder to start. Like "Vapor Lock", sort of.

you should replace the accumulator and/or the fuel pump check valve, and you'll probably be ok. Your mechanic can do a fuel pressure test, which will tell him if that's indeed what's going on.



If you're in a pinch or stranded or something, you can pull off the air filter and lift up on the sensor plate that's inside the airbox, and it will force some gas through the fuel lines; it will sound like a hissing, pinched balloon party. Don't do it for too long, though, or you'll flood the engine.

[Sirius Driver]

Originally Posted by Gogar

If you're in a pinch or stranded or something, you can pull off the air filter and lift up on the sensor plate that's inside the airbox, and it will force some gas through the fuel lines; it will sound like a hissing, pinched balloon party. Don't do it for too long, though, or you'll flood the engine.

with the ignition in the "ON" position right? Ok, thanks for giving me some understanding on how my fuel delivery system works. This is starting to make more sense.

[Gogar]

Yes, with the key on. There's a little microswitch on it that turns on the fuel pump (through a relay.) When you push up on it, you will hear the fuel pump turn on, and gas squeeze though the injectors. Just be careful.

And, if you take your air filter off, look in the airbox and see if there's a little valve in there that looks like the top of the exhaust pipe from an old tractor. That's the "popoff valve", which will keep your airbox from exploding if you have a backfire. It was an add-on fix and if it's not in there, you should get one. Preferably before you try the "lift up the sensor plate hot start" trick I just typed out!

Pics:
Pelican Technical Article: CIS Pop Off Valve Installation

[Sirius Driver]

Thanks! The car is original and just out of storage, so no Pop-off valve. Gonna order one ASAP! I'm just getting to know this CIS stuff.

[boyt911sc]

Originally Posted by Sirius Driver

Thanks! The car is original and just out of storage, so no Pop-off valve. Gonna order one ASAP! I'm just getting to know this CIS stuff.

Sirius Driver,

CIS (continous injection system) or technically referred as Ketronic fuel injection system is easy to learn and understand. Here are some of the most common acronyms you'll find in CIS troubleshooting posts: FP, WUR, AAR, AAV, FA, TTS, TV, FV, ECU, and words like control & system pressures, air mixture, vacuum leak, fuel gauge kit, etc.

Get hold of some fuel injection books by Watson, Probst, Aird, or an SC service manual by Bentley. The more you have hand's on experience in fuel injection, the easier to understand what the books are saying. There are plenty of help available in this forum. Good luck.

Tony

[T77911S]

i see you rplaced the cap and rotor, how about the plugs?

have the residual pressure checked, i would also have the control pressures checked at the same time

[Sirius Driver]

Nope no plugs. I'm kinda scared to do it. Ive always been scared of plugs ever since I had to deal with a cross threaded plug back in the 80's. I do em on my other cars but I'm afraid to it on this engine.