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> Won't start - 72 FI, used to start before engine drop
beemie96
post Dec 6 2009, 10:04 AM
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Interesting deal here:

Car ran a couple of years back but would die after driving it for about 2 miles. It idled fine for upwards of 20 minutes. I dropped the motor to clean everything off thinking maybe it was getting hot under load.

Now - engine is back in the car and it won't start. I got it to fire a bit by spraying gas into the intake but it dies pretty quickly.

checked for spark and have it at the end of all 4 plug wires (haven't pulled plugs)
I have fuel at all points i checked - injector banks, return line, etc. haven't checked actual fuel pressure - going to look at procuring a pressure tester - but the 1 and 2 injectors do spray ... and this is the part that confuses me - the 1 injector spurts when the key first goes to 'on' and the 2 injector spurts once while trying to crank, but then nothing. They don't spit out any more fuel while I'm trying to start the car.

I've been reading around here a bit and online and at pbanders site and I have a couple things I plan to check:

- double check the ground area under the intake manifold and clean all that up
- cold start injector - see if it's throwing fuel - it should be getting power while the starter is going, right?

I was also suspecting the trigger points - or maybe the connections between the points and wherever their signals go. Since the car ran before I don't think that they'd be 'bad', but I had a lot of stuff disconnected for a while during the cleaning of the engine and something may not be 'seated' properly.

So - I was hoping for some guidance on what to check while I'm in there.

Thanks!
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SLITS
post Dec 6 2009, 10:54 AM
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The injectors are triggered when the dizzy is rotating. Trigger points make and break contact must like ignition points.

#1 injector spurting fuel when the key was turned on just means that that pair was in position on the cam to be triggered. #2 injector spurting fuel while cranking would be normal ... they all should spurt.

The fuel pump runs for a couple of seconds when the key is turned on to build pressure in the system, then shuts down.

The fuel pump then runs while the engine is being cranked for starting.

Once the engine "catches" the fuel pump runs continuously.

If you don't have pressure and/or fuel pump run while cranking then the fuel pump, fuel pump relay, ECU and so on are suspect. You should be able to hear the fuel pump running when cranking the engine. Check wiring, fuse on relay board, relay on relay board, etc. You could also have a restricted supply line /filter and/or gummed up pump.

Cold start valve will only spray fuel if it is damn cold (or leaking)... activated by thermotime sensor.

You need a guage in the system to know for sure. Read PBanders site on D-Jet.
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beemie96
post Dec 6 2009, 12:05 PM
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Thanks - I've been reading pbanders site and plan to get a fuel pressure tester ASAP. I may not have been clear, though, about the injectors - they only spurt once - they don't spurt anymore after the first time.

So - maybe the pump is priming the system but not running after the initial start? That's an easy check... (it runs for 1.5 seconds initially)

Do I understand correctly that I probably have a good signal coming to the injectors if they're firing at all? Even if it's just the once? The issue could be fuel pressure for sure if that's the case.

I'll get a pressure tester on there and I'll also test for signal at the injectors.

Thanks!
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Spoke
post Dec 6 2009, 12:32 PM
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QUOTE(SLITS @ Dec 6 2009, 11:54 AM) *

Once the engine "catches" the fuel pump runs continuously.


I'm no D-Jet expert but when testing my D-Jet, the fuel pump on my system starts running when the engine is turning. It uses the contacts in the dizzy to determine that the engine is turning.

Given the information here, I would check to see if the fuel pump is running before checking the fuel pressure.

Is the connector for the contacts on the Dizzy on? If these are disconnected, the brain will not know that the engine is turning and will not turn the fuel pump on.

If the pump is on, then check the fuel pressure.
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bandjoey
post Dec 6 2009, 12:37 PM
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Recheck the wires. I worked for an hour trying to get my car to start, only to discover the coil wire was not on. Hopefully, it's something easy.
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underthetire
post Dec 6 2009, 01:05 PM
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Sound to me like it's not seeing the crank mode. I would jumper the fp relay to ground to run the pump. Then see if you get the squirts (IMG:style_emoticons/default/lol-2.gif) . If you don't its either fuel pressure or ECU/trigger points. Harbor freights ten dollar pressure gauge set actually works very well. I bought one just for the 914.
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beemie96
post Dec 6 2009, 01:34 PM
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Okay - that's a great idea - what pin do I jump to ground to force this?

QUOTE(underthetire @ Dec 6 2009, 11:05 AM) *

Sound to me like it's not seeing the crank mode. I would jumper the fp relay to ground to run the pump. Then see if you get the squirts (IMG:style_emoticons/default/lol-2.gif) . If you don't its either fuel pressure or ECU/trigger points. Harbor freights ten dollar pressure gauge set actually works very well. I bought one just for the 914.
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beemie96
post Dec 6 2009, 02:14 PM
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Old Problem like mine

Found this doing a search (from 3 years ago)

This sounds a LOT like my issue - so I'm going to find my spare set of points and swap it.

I'll still try grounding the fuel pump relay since that will be easy-breezy, but any tips on the trigger point swap? I know I need to lube the distributor and such - but anything else I need to be sure of? Is there a good way to 'test' the existing points?

Thanks again all!
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underthetire
post Dec 6 2009, 04:01 PM
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QUOTE(beemie96 @ Dec 6 2009, 12:14 PM) *

Old Problem like mine

Found this doing a search (from 3 years ago)

This sounds a LOT like my issue - so I'm going to find my spare set of points and swap it.

I'll still try grounding the fuel pump relay since that will be easy-breezy, but any tips on the trigger point swap? I know I need to lube the distributor and such - but anything else I need to be sure of? Is there a good way to 'test' the existing points?

Thanks again all!



Since your puling the dizzy anyway, you can check the points with a ohm meter and rotate the dizzy by hand. That will tell you if the points are working.
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beemie96
post Dec 6 2009, 04:08 PM
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First of all - thanks so much everyone! I can't wait to get in there and try to debug everything and get this going.

I'm going to pick up an inexpensive fuel pressure tester - this one good?

Pressure Tester
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saigon71
post Dec 6 2009, 08:56 PM
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QUOTE(beemie96 @ Dec 6 2009, 05:08 PM) *

First of all - thanks so much everyone! I can't wait to get in there and try to debug everything and get this going.

I'm going to pick up an inexpensive fuel pressure tester - this one good?

Pressure Tester


That is the exact tester I bought - it works well. Disconnect the fuel line from the cold start valve and tap in to the drivers side fuel rail.
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markb
post Dec 6 2009, 09:12 PM
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I had a car run just fine for 10 to 20 minutes, then the fuel pump quit. Turned out to be a bad relay board. Once the board got hot, it stopped working. Once it cooled, it started again.
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beemie96
post Dec 6 2009, 10:15 PM
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UPDATE -- The Car has started!

I spent the day researching and researching and something didn't feel right. The car ran before I pulled the engine, so it couldn't be anything major. Had to be a connection somewhere. I've read how important the points are, and I had verified that they were connected, but I found a couple articles that mention the MPS so I went down to the garage and checked that connection -- it wasn't seated all the way... it is now.

So - 10 seconds of cranking later ... vroom vroom!!!

I couldn't revel in it too long, though... don't have the exhaust hooked up...

So - now to hook that up and then I plan to get that pressure tester and make sure the pressure is good.

Thanks again to all!
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markb
post Dec 6 2009, 11:16 PM
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Congrats!
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