Engine dies but restarts after 2 minutes, Help please! Only a couple weeks left to drive in MN Options

[SteveL]

74 1.8 with L-Jet. Starts and runs perfect for a while.
After driving or running for anywhere between 5-20 minutes, the engine loses all power, but still sounds like it is running for about 20 seconds, then dies completely. While it still sounds like it is running, I can put the pedal to the floor and it makes no difference. If I try to start it right away, it will not start. Every time so far, after I wait a couple of minutes it will restart and run like nothing happened for a few more minutes, then die again.
I have replaced the dual relay with a known good.
I think the next suspect is the fuel pump. I see a T fitting in the driver side fuel rail that is plugged by a bolt. Is that where I would connect a fuel pressure test gauge?
Is that the best next step to check?

[jcd914]

I think the next suspect is the fuel pump. I see a T fitting in the driver side fuel rail that is plugged by a bolt. Is that where I would connect a fuel pressure test gauge?
Is that the best next step to check?

Yes that is where you would hook up a fuel pressure gauge.

Suspecting the Fuel pump is a good next step.
You can also hook up a test light to the fuel pump circuit to see if the pump is getting power or not.

If I am remembering the L-jet system correctly, with the key on but engine off, pushing the flap open in the AFM should make the fuel pump run. You can check for power and pressure in a single test.

Jim

[dr914@autoatlanta.com]

excellent advice, the only other thing is if the flap is sticking it would die then the flap would unstick and one could just drive off, especially if it sort of runs like it is running out of gas, it would be sort of flooding out

I think the next suspect is the fuel pump. I see a T fitting in the driver side fuel rail that is plugged by a bolt. Is that where I would connect a fuel pressure test gauge?
Is that the best next step to check?

Yes that is where you would hook up a fuel pressure gauge.

Suspecting the Fuel pump is a good next step.
You can also hook up a test light to the fuel pump circuit to see if the pump is getting power or not.

If I am remembering the L-jet system correctly, with the key on but engine off, pushing the flap open in the AFM should make the fuel pump run. You can check for power and pressure in a single test.

Jim

[porschetub]

excellent advice, the only other thing is if the flap is sticking it would die then the flap would unstick and one could just drive off, especially if it sort of runs like it is running out of gas, it would be sort of flooding out

I think the next suspect is the fuel pump. I see a T fitting in the driver side fuel rail that is plugged by a bolt. Is that where I would connect a fuel pressure test gauge?
Is that the best next step to check?

Yes that is where you would hook up a fuel pressure gauge.

Suspecting the Fuel pump is a good next step.
You can also hook up a test light to the fuel pump circuit to see if the pump is getting power or not.

If I am remembering the L-jet system correctly, with the key on but engine off, pushing the flap open in the AFM should make the fuel pump run. You can check for power and pressure in a single test.

Jim

(IMG:style_emoticons/default/agree.gif) with the George ,the flap can stick and leave you with no feedback to fuel requirement @ a given throttle position ,it needs to be free moving and snap closed quickly on the quadrant spring,posted recently about this and think the backfire story is a myth,mine has a vent disc and is sticking,the air flap is not a part easily bent,IMO its just wear as the air gate rubs on the lower cover plate when worn.
A guy on the bird has opened one up and proved that...good reading.
By all means check fuel pump function and check for a bad coil that is breaking down also.

[SteveL]

[/quote]
(IMG:style_emoticons/default/agree.gif) with the George ,the flap can stick and leave you with no feedback to fuel requirement @ a given throttle position ,it needs to be free moving and snap closed quickly on the quadrant spring,posted recently about this and think the backfire story is a myth,mine has a vent disc and is sticking,the air flap is not a part easily bent,IMO its just wear as the air gate rubs on the lower cover plate when worn.
A guy on the bird has opened one up and proved that...good reading.
By all means check fuel pump function and check for a bad coil that is breaking down also.
[/quote]

Thank you for the guidance, it is greatly appreciated. When it dies, I will be driving along at 1-2k rpm, so the flap would not be closed. And, even if the flap was closed, the car would still idle, correct?
I hadn't considered the coil. Do coils fail in an intermittent fashion like this? If so, I see RockAuto has an NGK coil for about $15, so easy to just replace in case (or do I need a Bosch blue coil at like $65?).
Thanks again.