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Discussion Starter #1
I tried to setup better testing for my problem:
To start with, this car runs absolutly wonderful - other than this.
Will not re-start after bringing the engine up to normal operating temperature – Every single time. It cranks fast, no fuel problem, just no Fire in the hole!
Get the engine up to temp and turn it off. It will re-start if you try right away, but if you wait 10-15 minutes before trying to re-start, it will not restart. It will start up just fine after one hour or more of sitting and cooling down.
The first thing I did was change all the filters even though they had been recently changed.
Then I checked the fuel lines many times and ended up putting a few clear vinyl hoses on the fuel plumbing so I can actually see the fuel moving and verify that it is not leaking, not loosing prime, and does not have air bubbles in the fuel from any bad fittings. I have a clear vinyl hose from the filter to the in port on the injection pump. Pretty cool, but it only verified that fuel does not seem to be the problem.
6 times I took the car out from cold starts on a 8 mile loop to get it warm and see if it would re-start. Once I got it up to temp and turned the car off if I waited 10-15 minutes it would never start – not once.
So, On a cold engine I cracked an injector line open on top of #3 injector to see fuel and estimate the pressure squirt. Powerful squirt of fuel flying up about 6 inches.
Same test on same injector after the engine is up to normal operating temperature and does not re-start shows a slow puddle of fuel on the injector head - No squirting of fuel at all – no pressure squirting fuel.
It has to be something in that injector pump.
Please see what you can find out for me. Maybe there is a setting I can adjust. Maybe I just need a different injector pump?

Other than that, this car runs like a champ. Plenty of power, idles as smooth as silk when cold or hot. The engine never chugs or misses when cold or hot. When cold it starts up on 3 revs.Please help if you have any ideas I can try.
 

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Roy, has this problem been getting worse over a period of time or did it just suddenly happen?
 

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It's not the injection pump itself, as those are rather "dumb" devices that either work or they don't. You've got some sort of problem with air entering the system, or an inability to move fuel throughout the fuel circuit. One thing you can do is to remove the line from the fuel pump (on the side of the injection pump), and see if it's working when the engine's turning over while warm. Also, you can disconnect the fuel feed line that goes into the fuel pump and run it directly to an alternative source of fuel--like a small fuel can. This will help determine whether there are blockages of fuel between the engine and main fuel tank.
 

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Discussion Starter #4
No start after getting up to temp - thanks for help

Thanks for your imput.
This no start after getting car up to temp happened suddenly - I believe. It was difficult to fix on the scenerio because typically I would drive to work or somewhere and not restart the car for hours later when it is time to come home. So, it isn't often that I created the situation of running it until fully up to temp - turning it off to go in a store or something quick and trying to restart after about 10-15 minutes.
The last mechanical work done on the car was 3 weeks ago for the air conditioner. The mechanics had to do some electrical tracing to find that a coolant temp sensor was broken. They replaced the sensor and wire connections. It was 2 days later I had the first real hard start (nearly drained the battery cranking). Had the 2nd hard start a few days after that, followed by 1st time it wouldn't start at all (until I returned to the car 2 hours later and it started up no problem). So, it has been a difficult mechanical scenerio to figure out, but now that I do have it figured out I can duplicated it without fault. Bring it up to temp (fully up to temp), turn car off, wait 10 minutes - it will not start. NOTE: If I wait 18 minutes or more and crank it a little I can see the temp guage on the car go down like it sucks coolant through the engine. If I wait like 5 minutes and crank it a little again, the 3rd time with cranking effort I can usually get it started. Still, I believe it is all associated with temperature at some component.
Car is Still Not Fixed.
Keep up the ideas
Thanks
 
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