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Question Fuel Issue

Hello,

After having my '74 under autopsy for months I decided to finish it up and try to get it running again. Everything went well but now I cant get it started. It has spark fine (with a new Crane EI system) but it seems that its not getting fuel. It started up only when I poured some fuel down the throttle body. I didnt really change anything that would effect the fuel delivery besides changing the injector seals. Any help or advise would be greatly appreciated.
Old 11-03-2001, 03:40 PM
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Stab in the dark these FI systems are pretty dependant upon vaccuum and fuel pressure. Is your fuel pump running when you turn the key? are you getting fuel pressure at the injectors. Is there a signal to the injectors to open? Keep us informed of what you have and don't have. Someone can surely do better than I to help you.
Old 11-04-2001, 06:40 AM
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Check the fuel pump to see if you have pressure...fuel supplied to the injectors...I had rust build up inside the pump...caused the pump no to spin...BTW the rust was from cleanning the pump some months earlier. Only a few drops will cause it to rust and freeze up... use a jumper at the relay board to run the pump. Pull off the supply line to the engine and catch fuel in a container of some kind. If you can get fuel to the engine bay then start looking at other problems...Fuel pressure regulator..doubt it. Trigger points? Verify that the injectors are working by turning on the ignition and operating the trottle. The TPS should send a pulse signal to the injectors....sort of a BBRRRRPPP sound should be heard. depending on the trigger position either injectors 1 and 3 or 2 and 4 should operate...or something like that. Also make sure you have the fuel lines connected correctly...supply and return.
Old 11-04-2001, 08:36 AM
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Thanks for info. I know the pump is working as I can see fuel coming in thru the lines..and bubbles passing thru the return line. I had a fuel leak down at one of the injectors after trying to start it so that would seem to verify fuel is getting down there. I can hear the Brrrrp sound after turning on the ignition..I was assuming that was the cold start valve. I was thinking maybe the timing was way off? Since I had to remove the dizzy and do some work on it (of course forgetting to note the position) I think maybe that might be the culprit so I located the TDC mark on the impeller making sure the rotor was pointed to the notch on the housing at the same time. Is this enough to get it in the ball park to start?
Old 11-04-2001, 08:55 AM
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The fuel pump goes "buzzz" for about 1.5 seconds when the key goes from "off" to "on".

The "BRPPP" they're talking about is the rattling of the injectors opening and closing. They should do that when the key is "on" and you open up the throttle.

--DD

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Old 11-04-2001, 01:42 PM
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Well I beat my head against the wall all day on the car. I took one of the injectors off to see if they were working. The only fuel that came out was when the fuel pump came on for the 1.5 seconds..when the engine was cranking no fuel came out. I was thinking perhaps the dizzy had something to do with it. Since I had to take out the points to install the Crane optical trigger I was wondering perhaps I took out something I should have left in?
Old 11-04-2001, 03:21 PM
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It is my understanding that there are three circumstances where the fuel pump should run:
1) For ~1.5 seconds when the key goes from "off" to "on".
2) Any time the starter motor is cranking.
3) When the FI trigger points trip.

Make sure you plugged the trigger points back in.

--DD

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Old 11-04-2001, 09:40 PM
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Is it a 1.8 or 2.0? Dave says 'make sure you plug the trigger points back in', which is key on a 2.0 D-Jet. I'll assume you didn't remove them by accident when putting in the Crane system. Even if you did plug them in, make sure the trigger points are good and adjusted properly. (I have an L-Jet, so others will have to help with the adjustment procedure).
Old 11-05-2001, 04:21 AM
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DOH! Sorry, got caught up in D-jet mode again. Tiramisu, if your car is a 1.8 then you'll have L-jet EFI instead.

The L-jet system will only run the fuel pump when the flap in the air flow meter is opened. It only has to be open a little bit for the pump to run. That completes a circuit through one part of the "dual relay" which then sends power to the pump.

--DD

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Old 11-05-2001, 07:29 AM
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I have a 74 2.0 which makes it a DJet I believe. I didnt mess with the trigger points at the bottom of the dizzy..just the points up by the rotor. Im thinking something is wrong with the TPS and Im gonna check the grounds today..then I guess I will have to breakout the multimeter and start probing. I got a new tranny ground strap to install as well.

Thanks for all the great help. I will advise of progress.
Old 11-05-2001, 09:02 AM
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If the engine was cranking there should have been some fuel spraying for each time the injector fired. If fuel comes out when you initially turn on the key that means the injector is either being told to open or is leaking, but since they don't let fuel out when cranking that seems remote? Turn on the key and manually move the throttle, you should hear the injectors fire. If one is pulled, then it should spray. If it doesn't spray and it is firing then there is not enough fuel getting to it. Try putting a guage on the line to see what pressure is? Good luck.
Old 11-05-2001, 10:31 AM
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John,

Thats the problem..the injectors are not firing when I move the throttle..I cant hear them click or anything.
Old 11-05-2001, 11:02 AM
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You solved it!
Old 11-05-2001, 11:52 AM
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Well after a week of frustration the car started up. It was the FI grounds as suggested by Bowlsby. I cleaned them with electrical cleaner (dirt gushed out) and then sanded the contacts. The TPS started working after that. The engine is very rough with lots of smoke (sounds like timing) but it did start thanks everybody for the help
Old 11-05-2001, 03:22 PM
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