75 1.8 won't start when warm Options

[loghome1814]

I have a 1975 914 1.8 that turns on from cold and runs great, until I turn the key off, then it won't restart. I will turn, start and immediately die. It will do this twice then it will only crank. Is it possible the ignition switch is cracked or going bad. Any ideas why it won't start. I have replaced the following:
points
plugs & wires
dist. cap & rotor
Condenser

When it is running from first start of the day, it runs smooth and strong. Also, if I let it cool down for a couple of hours it will start most of the time.

[jsayre914]

its not the ignition swith, you said it will crank.

is it fuel injection.... if so ....

probally the fuel pump. When you get it hot, turn it off. turn the ignition to the on position, go into the bay and pull the air flow meter off the big tube, stick your hand in the meter and activate the pump, you should hear the pump goin. you can also check the fuel pressure with a guage and see that it is gettin pressure.

i am on my second pump, first one did the same thing.

(IMG:style_emoticons/default/smile.gif)

[loghome1814]

its not the ignition swith, you said it will crank.

is it fuel injection.... if so ....

probally the fuel pump. When you get it hot, turn it off. turn the ignition to the on position, go into the bay and pull the air flow meter off the big tube, stick your hand in the meter and activate the pump, you should hear the pump goin. you can also check the fuel pressure with a guage and see that it is gettin pressure.

i am on my second pump, first one did the same thing.

(IMG:style_emoticons/default/smile.gif)

I will do both, thanks for the suggestions. I have owned the car for 26 years and still have the original fuel pump in it. By original I mean the one that came with the car from factory, so that could easily be my problem.

[Drums66]

.....I'm thinking AAR (IMG:style_emoticons/default/idea.gif)
or combo, fuel pump (IMG:style_emoticons/default/idea.gif)
(IMG:style_emoticons/default/bye1.gif)

[r_towle]

I would suggest you check your fuel pump pressure or just step up and buy a new pump (IMG:style_emoticons/default/smile.gif)
That old pump owes you nothing.

Rich

[loghome1814]

I would suggest you check your fuel pump pressure or just step up and buy a new pump (IMG:style_emoticons/default/smile.gif)
That old pump owes you nothing.

Rich

Rich:
Checked the pump amd it doesn't work when the AFM flap is moved with the key on. I can hear the relay click, but the fuel pump is running. New fuel pump tomorrow. Thanks

Kevin

[malaga_red75]

Kevin,

This same thing happend to my 75 1.8, 4 or 5 years ago. For me it was the Cylinder Head Temperature sensor (CHT).

Started great first time of the day then if i turned it off it wouldn't start until it cooled down.

If it isnt the fuel pump, I would try this next.

-Peter

[jsayre914]

Glad you are on the way to figuring this out. My first pump went out on the expressway, when there was heavy traffic and construction.... and all cars were forced into one lane.

behind me (IMG:style_emoticons/default/rolleyes.gif)


moral: after that experience i keep a spare pump

[Tom]

My 76 2.0 has somewhat the same problem sometimes. It is D-jet, but both injection systems use a temp sensor in the head to adjust fuel mixtures depending on engine heat. Problem comes up because the aluminum head cools off quicker than the cylinders and the temp sensor sends a need for richer mixture because engine is cool. Actually the engine is warm and the rich mixture makes it hard to start. Try this, next time before cranking the engine after warmed up and turned off, fully depress the throttle before turning on the key. Keep it down and crank. If it starts and keeps running, then you will know it was getting a rich mixture. I don't know how the L-jet throttle works, but on D-jet as you depress the throttle, the ECU sends an extra "shot" of fuel to the cylinders thru the injectors, that's why you need to depress the throttle before turning on the key. Hopefully the L-jet works similar. This was from a thread I posted a few years ago and Brad Anders answered it for me. It works for me on my D-jet. If you want ot search, it was titled something like " hard to start when warm".
Also, in the owners manual, it says to fully depress the throttle to start.
Hope this will help,
Tom

[RFoulds]

Kevin,

This same thing happend to my 75 1.8, 4 or 5 years ago. For me it was the Cylinder Head Temperature sensor (CHT).

Started great first time of the day then if i turned it off it wouldn't start until it cooled down.

If it isnt the fuel pump, I would try this next.

-Peter

I was thiunking same thing. I have had SOOO many of those go bad.