Possible fuel pump problem
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From: Aurora CO
Possible fuel pump problem
I have a 91 Bronco that just died on me today. It will turn over and is getting spark but no fuel is getting to the fuel injection. When you first turn on the ignition, you can here the fuel pump start and then it shuts off after about 3 seconds. Is this normal? I thought the pump would keep running. Can anyone help me with this problem?
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Joined: Feb 2004
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From: GOING BACK TO TEXAS!!!
pull codes from truck, then re-post what you find: for instructions, look here. I found it easier to get a digital code reader ($20) at the local parts store. Translate your codes with either the haynes guide or this website.
http://www.fordfuelinjection.com/?p=13
Welcome to FTE, and the search forum button at the top should be one of your best friends...
http://www.fordfuelinjection.com/?p=13
Welcome to FTE, and the search forum button at the top should be one of your best friends...
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From: Aurora CO
Thank you. I will pick one up tomorrow. Would be good to have. I did search after I put the initial posting and found a thread that said it was normal for the pump to come on and then shut off after 5 seconds for safety. I will post what I find out when I do. Thank you again.
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From: GOING BACK TO TEXAS!!!
Dadrich, a couple of other things...this helps us.
When you post, please put what year, size motor, mileage, tranny, and any mods that you have done to your truck... These things help. You are going to learn a ton about your truck when you pull the codes. Please post all of your findings here. Your active codes (first ones), and your history codes (after the single beep/flash). Anytime you think that you have something wrong, just use the code reader and find out what is happening. You can also pull your codes anytime.
Well, I hope your problem is much easier than a fuel pump. Dropping a fuel tank flat out sucks.
Tim
When you post, please put what year, size motor, mileage, tranny, and any mods that you have done to your truck... These things help. You are going to learn a ton about your truck when you pull the codes. Please post all of your findings here. Your active codes (first ones), and your history codes (after the single beep/flash). Anytime you think that you have something wrong, just use the code reader and find out what is happening. You can also pull your codes anytime.
Well, I hope your problem is much easier than a fuel pump. Dropping a fuel tank flat out sucks.
Tim
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From: Aurora CO
I ran a code check today (91 Ford Bronco w/351,5.8 EFI). The only code that came back in memory was 634 (MLP sensor voltage higher or lower than expected). I already new that my transmission needs serviced (on my list of things to do) but nothing else came back (except for the usual reading on the air charge temp sensor/114, the coolant temp/116 and transmission temp/636 which I could probably expect since its cold and the truck has been sitting for a few days. The fuel pump does come on and then shut off after 5 seconds and then comes on when I try to turn it over. Now dont laugh, but I haven't changed my fuel filter in a LONG LONG time. Could the be the culprate?
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Joined: Feb 2004
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From: GOING BACK TO TEXAS!!!
this may be a stupid question, but on your dash, does it say "fuel reset", or have you tried to reset your inertia switch. Your fuel pump should NOT run if it has been tripped, but check just for heck of it. Yes, your fuel filter may have something to do with it, but unlikely. Changing it now is a must. $7 worth of filter, and eliminating it as a problem. Are you positive that you are getting spark?
Your next bet may be to rent/borrow a fuel pressure testing kit from the parts store or someone you know. They are expensive, so beg/borrow/steal/deal. If you follow the testing proceedures (use the search button on this website, or post here again and I will type it out), you should get somewhere between 35 and 45 psi at the Schrader valve (looks like the same valve on your tire at the fuel rail on top of your engine on the driver's side.
Let us know
Tim
Your next bet may be to rent/borrow a fuel pressure testing kit from the parts store or someone you know. They are expensive, so beg/borrow/steal/deal. If you follow the testing proceedures (use the search button on this website, or post here again and I will type it out), you should get somewhere between 35 and 45 psi at the Schrader valve (looks like the same valve on your tire at the fuel rail on top of your engine on the driver's side.
Let us know
Tim
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From: Aurora CO
I just replaced the fuel filter and crank it over for a good ten minutes. I can now smell fuel under the hood so I am going to assume the fuel is getting into the intake. I just replaced the plug wires and plugs in fall of last year. I dont think I am getting any fire. Possible distributer? I would think that the trucks on board computer would have stored some type of kind code when it shut down. Like I said, strong odor of fuel under the hood so its getting there. Any ideas?
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From: Aurora CO
Tim,
One more question? How do you add your vehicle description on the end of your message? I am pretty sure you dont type it each time you send a response.
Thanks. Mike
One more question? How do you add your vehicle description on the end of your message? I am pretty sure you dont type it each time you send a response.
Thanks. Mike
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Senior User
Joined: Feb 2004
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From: GOING BACK TO TEXAS!!!
yes, your truck should have stored numerous codes about this...
how is the gapping on your plugs, and have you messed with the timing? a voltmeter that will read resistance thru your wires will help- are the rotor and distributor cap good? just trying to eliminate simple items...did you get a haynes guide or chilton's manual?- It is an easy way to chase problems.
how is the gapping on your plugs, and have you messed with the timing? a voltmeter that will read resistance thru your wires will help- are the rotor and distributor cap good? just trying to eliminate simple items...did you get a haynes guide or chilton's manual?- It is an easy way to chase problems.
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From: Aurora CO
Tim
I gapped the plugs per the specks when I put them in (cant remember right now) but I know I gapped them correctly. Other than the plugs and wires, I havent touched anything up top. I have a Chiltons manual. I always buy that first thing when I get an old one that I know I will spend time underneath. As far as the rotor and cap, not sure. They were the ones on it when I bought the beast in 2002.
Mike
I gapped the plugs per the specks when I put them in (cant remember right now) but I know I gapped them correctly. Other than the plugs and wires, I havent touched anything up top. I have a Chiltons manual. I always buy that first thing when I get an old one that I know I will spend time underneath. As far as the rotor and cap, not sure. They were the ones on it when I bought the beast in 2002.
Mike
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From: GOING BACK TO TEXAS!!!
Mike
go to the top of this page, where it says "forums", scroll over that so it brings down a menu. Click on register (even though you already have). It will bring up some error thing where it says if you want to edit your profile, click here. From there, I think it is under "Signature".
Apart from that, if you still have some light left or if the B is in the garage, pop off the distributor and check to make sure that there is a rotor on it, and that the end of the rotor has not separated. If it is still intact, then you will need to check from the wire to the plug. someone makes a "Spark jump" tool, that shows you the spark going across the connections, I don't remember who makes it. Hope all works out for you...I'll look on this message board again tomorrow. Some of the better people hit up with questions are MuckyPaws, Greystreak, and Kemicalburns. But everyone on here will help.
Tim
go to the top of this page, where it says "forums", scroll over that so it brings down a menu. Click on register (even though you already have). It will bring up some error thing where it says if you want to edit your profile, click here. From there, I think it is under "Signature".
Apart from that, if you still have some light left or if the B is in the garage, pop off the distributor and check to make sure that there is a rotor on it, and that the end of the rotor has not separated. If it is still intact, then you will need to check from the wire to the plug. someone makes a "Spark jump" tool, that shows you the spark going across the connections, I don't remember who makes it. Hope all works out for you...I'll look on this message board again tomorrow. Some of the better people hit up with questions are MuckyPaws, Greystreak, and Kemicalburns. But everyone on here will help.
Tim
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From: Aurora CO
Tim,
Thanks. I went into the edit profile and cant find the signature editing block. Maybe I will come accross it eventually. For now, the light is gone and unfortunately I currently live in a apartment complex with no garage (that will change the end of next month when I hopefully will have a house with a oversized 2 car garage, home for the beast). I will take a look under the distributor tomorrow morning and check the rotor per your advice and see what I find. I will let you know. Thank you again. Mike
Thanks. I went into the edit profile and cant find the signature editing block. Maybe I will come accross it eventually. For now, the light is gone and unfortunately I currently live in a apartment complex with no garage (that will change the end of next month when I hopefully will have a house with a oversized 2 car garage, home for the beast). I will take a look under the distributor tomorrow morning and check the rotor per your advice and see what I find. I will let you know. Thank you again. Mike
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From: Aurora CO
Time
Took a look at it this morning. Contacts in the distributor cap are EXTREMELY corroded along with the tip of the rotor. Ignition coil is EXTREMELY corroded also. Could be the problem. I would think though that if anything it would run rough, not run at all. I am going to go ahead and replace all three. Cant hurt. If anything, it would be one less problem down the road. Thoughts? I will post if it works.
Mike
Took a look at it this morning. Contacts in the distributor cap are EXTREMELY corroded along with the tip of the rotor. Ignition coil is EXTREMELY corroded also. Could be the problem. I would think though that if anything it would run rough, not run at all. I am going to go ahead and replace all three. Cant hurt. If anything, it would be one less problem down the road. Thoughts? I will post if it works.
Mike
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From: sunny fla sometimes windy
Don't forget the dielectric compound on the plug boots AND the Rotor nose to prevent corrosion of the contacts in the future!! I would check all the computer connectors for corrosion and clean them up since the sensor voltage is only 5 volts and the resistance of resistance based sensors is usually pretty low so any added will screw with them.
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From: Aurora CO
The beast lives!!!!! After changing the distributor cap, rotor and ignition coil which were all corroded it turned out to be the ignition module. Unfortuantely, my dumb @*$#^ lost one of the screws so now I have a small c clamp on the front of it until I can find somewhere to get a lousy screw to put in it. I figured it has to have the connection between the module and the distributor body to fire. Any ideas. I tried the local auto part stores and they just laughed. I am guessing the ford dealer or the junk yard. Mike