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Join Date: Aug 1999
Location: Morgan Hill, Ca, USA
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Engine dies 3 seconds after start

I have a 74 2.0 with the standard djet FI

I have never previously had any problems starting my car, even when it was 30 degrees and it had been sitting for a few days, it starts right up after 2 seconds of cranking.

Recently an odd thing happened. I was messing with my seat belt and was checking some of the connections that prevent the car from starting if the seat belt is not fastened. Several times I turned the key and cranked the engine then turned it off before it started. When I was done checking some connections in the seat belt, I went to start my car and it started right up, the odd thing was, it sounded quite loud and idled at 2000 for 3 seconds then died. I tried starting it again and the same thing happened. When I give it gas, it just dies. The only way I can keep it half alive is to tap the gas pedal every 2 seconds. It seems to rev up when I release the pedal, not when I push it. Any way, this sounded like a fuel problem to me. I had just changed the fuel lines between the tank and the pump and had not replaced the fuel filter. Thats the next thing I did and it didn't help. I have checked the injectors, and gas does come out but I'm not sure if its the right amount. I also checked the CHT and its working fine. I dont know the source of this problem, and I need some info and help.

PS. I also checked for kinks.
Thanks!!!

Danny Beardsley
Proud owner of a you know what

[This message has been edited by dbeardsl (edited 11-11-1999).]
Old 11-11-1999, 01:00 AM
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Ok, I have narrowed it down some more. I removed the fuel line right after the fuel pump and turned the key, as expected the fuel pump turns on, it spits fuel for 2 seconds then stops. I thought it wa supposed to spit gas till it was pressurized?
if the end is just spitting gas its not pressurized, why does it stop? please help! I have been working on this for a week.

Thanks,
Danny
Old 11-11-1999, 01:15 PM
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It only pumps for about a second when you turn the key from "off" to "on". The pump also runs when the engine is rotating. The trigger points in the distributor are what tell it the engine is running.

First suspect is everything you did to the car since it ran. You said you messed with the fuel hoses. Are they hooked up correctly? Check the hose diagram elsewhere on this site. Could be the fuel pressure regulator is hooked up backwards.

Have you checked *all* of the fuel hoses? The ones under the tank? The ones to and from the fuel pump under the engine? Kinks anywhere can result in similar behavior.

--DD
Old 11-11-1999, 02:08 PM
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Thanks Dave.

The car ran fine for several weeks after I changed the fuel hose between the pump and the tank. I replaced the filter after this happend. The only thing I messed with was the plugs that come out of the tunnel to connect to the seat belt and seat. I tried several different combinations, there are two plugs from the tunnel, one from the belt and another from the seat. There are no kinks in the fuel lines and the flow out of the fuel pump is fine. The pressure regulator is connected right. I am running out of culprits. Thanks though, any more info from anybody would be helpful.

Danny
Old 11-11-1999, 04:46 PM
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This is odd but I think the heater fan blower in the engine compartment and the fuel pump are on the same circuit. Does that fan come on? If not suspect the common fuse.
Old 11-11-1999, 05:21 PM
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could be the brain.
sounds like it is time to carb it.

------------------
Michael Scheid
(206) 232-9854
Old 11-11-1999, 07:00 PM
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Hmmmm, if you had just messed with the seat belt interlock relay, located under the passenger seat, its probably a 'bad' relay or wiring. These *things* are notorious for getting wet and rotting. I sure Dave D. will chime in and tell you how to bypass the relay, its also probably somewhere on this board. Take it away Dave!.......
Old 11-11-1999, 07:27 PM
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The thing is, I'm sure its a fuel problem, non electrical(unless its a fuse or something), cause it dies after 3 sec but I can keep it alive by tapping the gas pedal.
I also checked the TPS, its not that.
Old 11-12-1999, 01:05 AM
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A very good way to check if its a fuel problem is to pour a "dab" of gas into the throtle body. Crank it and see if it starts without you giving gas. Once started use carb cleaner and spray into the throat of the beast. This will burn and will run an engine at a very low idle. DO NOT USE STARTING FLUID. (Law suit safe now) Starting fluid is an extreamly powerful gas. It is very dangerous, I have seen it blow holes in engines from the blast. Everything needs to be correct to use starting fluid, and as you know its not correct right now.

Now heres another thought process. First the car sounds like your not getting enough air to burn your fuel. There is a very delicate mixture needed. So check that the air lines are open and clean. You already said that the fuel pump is working. I might check an injector though. Perhaps the FI box is sending bad info around. Cheking this is simple, just unscrew the injector and sensor unit and put the end into a 20oz pop(soda) bottle. Crank engine and see if bottle gets gas. If that works and you get a very good stream of gas then you should be able to deduce that it is an air problem.

Yet anohter idea of what might be wrong, heres what happened to me. I don't know if this will help. I removed the entire FI system, cleaned and put back on. In the process I moved the fuel regulator to the incomming fuel line, not the fuel return line. This caused very very close to the same problem. So, if you messed with this check it.

Hope any of this helps.
Good luck
Old 11-12-1999, 04:23 AM
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Well, I'm surprised DD didn't say it, but do the "Dave Darling Dance". Go through the ignition system, out of wack timing, a bad condensor (rare), burnt points (common), and fouled out plugs from all the bad running.

Could be the brain, see if the pump runs until the engine dies, or if the pump cuts out THEN the engine dies. ECU failures are also rare.

Could be running extremely rich. If the cold start vavle fails it will dump gas into the engine. Also if the vac hose to the MPS has a leak the MPS reads full throttle and dumps gas. See if the MPS holds vaccuum (use a "Mity Vac" sucking on it with your mouth isn't a great indicator). Don't pull to many psi 5-7 lbs is enough to see if it working. For the CSV just disconnect the fuel line (a good Idea would be to replace it with a properly mounted fuel pressure gauge).

One other odd-ball things thats happened to me.

The advance weights in the dizzy rust (south Florida, go figure ) and get stuck either no advance or full advance. Problem is you need to remove the points plate to see the advance weights.

On my 75 2.0L there was and inline resistor to the CHT that was bad, but it was only a problem after warm.
Old 11-12-1999, 10:28 AM
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Hey, I found it. It was the MPS. it didn't have a vacum leak, cause it could still hold a vacum, but I think the piston inside froze up. the resistance between pins 15 and 8 is supposed to be about 90 and its supposed to move up or down when a vacum is applied, mine is stuck at 96ohms. The resistance between pin 15 and 7 is supposed to be 350, but mine isn't even connected ie infinite resistance. when I unplugged the vacum line from it, the car ran, it still sounded not so great, but it ran, and it revs. So shoulld I get a new one, or a used one for cheap.
Old 11-13-1999, 12:17 PM
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