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Discussion Starter · #1 ·
The other day I turn on my engine just fine when all of the sudden it turned off by itself. I tried turning it back on but it just cranked so I left it alone since it was late. The next day I was able to turn my 1991 LX on but when I pressed on the accelerator the engine wanted to turn off and then when I depressed it it would go back to normal idling but after like 3-4 seconds the engine would turn off again. Now (after a week) I am just able to crank the engine but nothing else happens. I hear the buzzing noise in the back (when I turn the ignition switch but right before I make the engine crank) indicating the fuel pump is working (right?), I changed the spark plugs and that's about it. My engine just cranks now so i am wondering what the problem might be. Does anyone have any suggestions. (I went to Autozone and they told me that it might be the ignition coil or the ignition module). I really don't feel like taking it to a shop (Pep Boys?) and getting a computer scan. I would appreciate any advise.
 

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If a shop is an option you want to avoid, need to get hands dirty and get some tools and measuring equipment.

Need to check for spark at the plugs and the coil and a fuel pressure check. The FP might sound like working but, it cannot supply the pressure needed for startup. Need to get these items check first, in preparation for step 2. Replacing parts without checking would be like playing dice. And it can get expensive. GL
 

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Discussion Starter · #3 ·
Thanks Joel5.0.

How would I be able to check the fuel pressure. Is there a certain device I need? I checked to see if the fuel line had pressure by undoing the fuel line cap (right by the alternator- it looks like a bicycle tube's air pressure valve) and so I pressed down on the valve while my dad turned the ignition on and I did get some gas to come out. Does this mean that there is pressure? I also checked to see if there was spark at the coil and there was but I noticed that the ignition coil itself was really filthy (and the area adjacent to it too)on the outside and it looked like it had never been replaced. Besides, everything on my 1991 LX (I recently purchased it) is stock. The previous owner took really good care of it (so he says) and I believe it because it passed the smog check very smoothly. I'm going to try checking for spark at the plugs and take a look at the ignition module (would you know where this is located?). It might just be that the fuel pump is not working properly so if nothing works then I'll take it to a shop.
 

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You need a fuel pressure gauge that attaches to the test port you mention. Anything below 20psi will give you problems, normal reading is 40psi....and 20psi looks like high pressure when you eyeball it.....Anybody you may borrow it from? GL
 

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Discussion Starter · #5 ·
Excellent, thx for the advice. I'll locate a fuel pressure gauge and test it. I hope it is actually below 20 psi so that I can feel comfortable sending it straight to the shop to change the fuel pump.

The car is bone stock right now but I do intend to increase its overall performance. Can I purchase a higher performace fuel pump as of now before I make any mods? I don't know how many lph the stock pump is, but can I get, say, a 110lph or 155lph or does it depend as a function of the modifications done already?

(thanks for the advice/comments, anyone)
 

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josegome said:
Excellent, thx for the advice. I'll locate a fuel pressure gauge and test it. I hope it is actually below 20 psi so that I can feel comfortable sending it straight to the shop to change the fuel pump.

The car is bone stock right now but I do intend to increase its overall performance. Can I purchase a higher performace fuel pump as of now before I make any mods? I don't know how many lph the stock pump is, but can I get, say, a 110lph or 155lph or does it depend as a function of the modifications done already?

(thanks for the advice/comments, anyone)
If it is the pump, (I suppose a bad relay could cause this too) get the 155, alot of people seem to run 'em. I kind of wish I'd gotten one, but the old Mustang magazine article I was using for a guide, said that 155 was too big for a stock car. Although, you could get an adjustable regulator, and trim some pressure.
 

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meangreen92 said:
If it is the pump, (I suppose a bad relay could cause this too) get the 155, alot of people seem to run 'em. I kind of wish I'd gotten one, but the old Mustang magazine article I was using for a guide, said that 155 was too big for a stock car. Although, you could get an adjustable regulator, and trim some pressure.
Im getting ready to change mine to 255 lph :drool:
 

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Discussion Starter · #8 ·
If 155lph is too much on a stock car, does it mean that it will just waste more gas than it already does?
 

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josegome said:
If 155lph is too much on a stock car, does it mean that it will just waste more gas than it already does?
The OEM pressure regulator and the ECM usually take care of that; an adjustable FP reg. wouldn't hurt though.
 

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Well, the article said it would "load up" the injectors or something like that. It was from 1992. I'll bet the bigger pump draws more amperage.
 

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Discussion Starter · #11 ·
The problem was my fuel pump. Thanks guys.
 
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