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truck turns over a lot before starting. fuel pump??

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XHitman396

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my stock '87 turns over quite a few times before it starts. it turns over fast and strong, just more than it should. would this be the fuel pump. i know my buddy had this problem in his Grand Cherokee, and it was the check valve in the fuel pump mounted in the gas take. when he turned the jeep off, the check valve wouldnt seal all the way, and the gas would seep back into the tank, so it would crank until the gas reached the engine. i changed the fuel pump for him, and everything worked perfectly after that. have you guys had the same problem with your trucks? did you try the pump?? the filter isn't THAT old either.. but maybe time for a change...
 
had the same prob on mine with the fuel pump. gas ran back to the tank and had to crank till it reached the carb. being carbed I have to pump the pedal a couple times before it will start otherwise it will just crank over for a while before it starts. since yours is tbi you shouldnt have to pump the pedal first but you might try it before you spend the money on a new pump.
 
Mine does the same thing. Ignition is fine, when I built the new engine I replaced the distributor, installed accel cap and rotor, msd coil, and msd 6T. Still did the same thing. I have tried cycling the fuel pump several times before trying to start it, thinking the check valve was the problem as well. Didn't help at all though. It isn't a big problem so I haven't done anything to try and fix it. I would be intersted to see what you find though
 
JEBSR said:
Mine does the same thing. Ignition is fine, when I built the new engine I replaced the distributor, installed accel cap and rotor, msd coil, and msd 6T. Still did the same thing. I have tried cycling the fuel pump several times before trying to start it, thinking the check valve was the problem as well. Didn't help at all though. It isn't a big problem so I haven't done anything to try and fix it. I would be intersted to see what you find though
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Is yours a carb or TBI? Mine (TBI) does the same thing - always has. The fuel pump died, I replaced it, and it still takes a few seconds worth of cranking before it lights. Once it is warm it starts faster. I will have to ask my mechanic buddy at the Chevy dealership if this is normal or not. :dunno:
 
TBI, has done it since I bought it. Never created any problems. That's why I haven't checked in farther.
 
whenever i start my '94 c1500 (yep, tbi), i turn the key to the run position only, leaving the start circuit open, for about 10 seconds, to let the fuel pump pressurise the lines, then go ahead and turn the key to start. it fires us fast. if i go straight to "start" which, of course, closes both the start and run circuit, it takes longer, since the fuel pump is repressurizing the lines while the motor is cranking. just extra strain on the battery and starter, i say. i know the system is supposed to stay pressurized for a while, but in reality, they tend to wuss out overnight. no big deal, imo.
 
The fuel pump shuts off 2 seconds are ya do that, so no need to wait for 10 seconds. ;) I start our '94 Sub the same way. It starts much quicker in the morning if the pressure is up before cranking. :cool1:
 
I'd be testing the fuel pump relay by forcing the pump to run before starting on ALL of the trucks mentioned in this thread.

I'd suspect TBI is the same as TPI for the starting where the ECM is concerned, and as I recall, it's 8 reference pulses (8 "sparks") before the ECM commands injector pulses. So you will have SOME hesitation no matter what you do, but when the relay fails, as some in this thread know, the oil pressure switch handles fuel pump running, and it takes approx. 5PSI before it will kick the fuel pump on. Thus, bad fuel pump relay=delayed start.

This is NOT a statement that you should go out and replace the relay just because it takes a long time to start. Test the relay, then replace if it's the cause.
 
yeah, the relay thing sounds like it could be the culprit. where is the relay, and how exactly do you test it?? thanks for all the help, guys..
 
I have the Holley 950 Commander TBI MSD 6 & distributor.

Allmost every time I start the engine I have to crank it too long in my opinion.
I have the fuel pump on and I have a fuel pressure gauge so I know there is fuel pressure before I start to crank. It still does it.

The MSD 6 got water in it once (my bad, stupid location for it) and whitout the MSD box it starts right away, every time?

Could it be the voltage dropping too low for the MSD box?
 
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