EFI starting question???

[broncobear22]

When I go and start my bronco it takes a long time for it to crank over and start. I found that if I crank it for about 20 seconds let off and then crank again it starts quicker. It runs beautiful when running just getting the damn thing to start is kinda of pissing me off. Any suggestions? I'm leaning toward either the fuel pressure regulator or a mini torque starter. Anything else I might look at?

 

[BabyBlue69]

This sounds like the big "crank" vs "start" debate. What do you mean by crank and start? Does the starter turn the engine over quick or slow? Does it take a long time for the engine to turn over or actually run on its own?

If it turns over slow that could be the starter, battery, electrical connections, timing...
If it turns over OK but takes a long time to run on its own it could be fuel pressure or an ignition problem.
Fuel pressure could be broken down into a bad regulator, bad pump, clogged filter, etc but I would check to make sure that the electric pump is actually running when you turn the key to the start position.
Ignition problems could be anything from timing to plugs/wires, distributor cap and rotor, coil, etc. Once again I would ensure that the coil is getting power when the key is in the start position.

How long have you had the problem, ever since the EFI conversion?

 

[RolledItAgain]

This sounds like the big "crank" vs "start" debate. What do you mean by crank and start? Does the starter turn the engine over quick or slow? Does it take a long time for the engine to turn over or actually run on its own?

If it turns over slow that could be the starter, battery, electrical connections, timing...
If it turns over OK but takes a long time to run on its own it could be fuel pressure or an ignition problem.
Fuel pressure could be broken down into a bad regulator, bad pump, clogged filter, etc but I would check to make sure that the electric pump is actually running when you turn the key to the start position.
Ignition problems could be anything from timing to plugs/wires, distributor cap and rotor, coil, etc. Once again I would ensure that the coil is getting power when the key is in the start position.

How long have you had the problem, ever since the EFI conversion?

BabyBlue said it all

 

[broncobear22]

Ok, want some info

It cranks good, it just cranks then will start after about 20 seconds of cranking. It's like when you had a carb on it, and you had to start it when it was cold. If i get it started let it run for awhile then shut it off and start it right back up it starts like it should, right away. Fuel pump is working when the key is to the on position and filter is brand new. There is spark from ignition when I'm turning it over. I replaced the cap, rotor and spark plugs and wires. Like I said when it is running it runs like a banshi!!!
I think it is the pressure regulater. Any other suggestions?

Also, I gapped my spark plugs for the T-bird would that change anything?

thanks guys so far

 

[RRRAAAYYY2]

First and foremost, every starter ever designed and used in an automotive application is rated for 5 seconds crank, and three minutes rest. So when you exceed the 5 second crank you are damaging the starter, and the battery, and the wiring.
It is not overly unusual for a 5 second crank cold, and instant start hot. But 20 seconds is freaking way too long. My thought, uneducated guess, is you are not getting enough fuel through the system. Almost like it is draining back through the lines. But like I said it is just a guess.
Another option is the starter is not spinning fast enough, but this usually would get worse when it was hot.
I would look for a timing, air, fuel mixture problem first. Maybe throw a used starter in to see if it changes anything. But I doubt it is the starter right now. At 20 seconds cranking though, it will be your starter shortly.

 

[broncobear22]

I don't want to burn up the starter, it is turning good. I think that the fuel is draining back in to the tank. That would be the fuel pressure regulater, right?

 

[77B]

Check the (ACT) Air Charge Temp Sensor. It measures the temperature of the air entering the engine ie. increasing or decreasing fuel mixture during cold start. It is mounted on the upper intake around the rear. Inexpensive part and easy to change.

I hope this helps and let me know how it turns out

 

[supermottl]

My 92 BB 351 had the same problem, replaced fuel pump since it was going and it still did the same thing. Finally, FPR died completely and hydrolocked one cylender with liquid fuel . finally towed it in and it was the FPR... not that expensive... try that first

 

[SaddleUp]

You stated that the fuel pump is working in the on position. Is it also running in the crank position? (It is possible to hook it up to the run position rather than the crank/run one)

I don't have my Probst EFI book handy but you can use a pressure guage to narrow down a fuel supply problem. I.E. There are pressure checks you can do at the fuel rail to determine whether an injector is leaking, the regulator is bad, or the fuel pump is bad. Any one of them can cause hard starts when it is cold that are related to fuel supply.

 

[broncobear22]

The pump is working when on and cranking. It is not the pump. I don't have a shredder valve on my fuel rails so I don't know another way to check fuel pressure. It has a hard time starting when it is hot also. if I let it sit for about 5-10 mins. when hot it will do the same thing. The only time it ever starts right up is when I shut it off and start it right back up. I'm really leaning towards the fuel pressure regulater. Does that sound right?

 

[66horse]

Try this test. Turn key on for five seconds. Turn key off. Turn key on for five seconds. Turn Key off. Do this five times. See if it starts any quicker. Report results.

 

[broncobear22]

I normally do that for a few times, I will try it five times tonight and see what that does. I only do it for two times before I start it.

If that doesn't change anything then what? and if it does then what?

 

[RKM]

He is just checking to see if you loose pressure when off. Turning the key about 5 times will hopefully get fuel from the tank back up to the injectors and it should fire a lot easier.

You really need a shrader valve....Sucks you don't have any way to trouble shoot the pressure. Could be 2. things that I can think of.

1.Bad check valve in an intank pump.....If you have an intank pump. Or you may have a check valve that is bad in an inline pump. I think they have them also. Obviously it keeps pressure in the fuel system or at least fuel in there for the next time you fire the rig.

2.Fuel pressure regulator. These usually go bad all at once. At least in my situations. No fuel, lack there of etc. Sometimes getting stuck dumping fuel not starving you of it.


The air sinser isn't going to do that much. At least not what you are discribing. Back in the Mustang racing days it was rumored that you could pull this sinsor and make it cold, thus tricking the computer to run richer. Their were many dyn tests in Muscle Mustang & Fast Fords that proved this theory wrong. It showed no signs of anything on the dyno with an AFR meter. I think it is a temporary sinsor that works in the inital key on position until the motor starts and then it goes off.

 

[SaddleUp]

You can still put a T in the line to check fuel pressure. My guage even came with the stuff to do it even though I use the shrader valve. My brother had his pressure regulator go bad and it acted the same way as yours does but all of the information we could find said that it could also be leaking injectors or the check valve mentioned above. Once we ran the fuel pressure tests we were able to determine which one was the actual problem. If injectors are leaking and your using a SEFI system rather than a banked one then you can let the ECM do a cylinder balance test (KOER) which may turn up a bad injector. I think Ryan probably has the directions for the cylinder test on his site. You can also pull each injector plug and see if the engine rpms change (it should) but it can be hard (or even impossible) to get to some of the injectors with the intake on.

Note: The fact that you are in the habit of turning the ignition on and off twice indicates that the problem is almost definately a fuel bleed down problem.