Fuel Pump issue, Code 542 (going bad fast)

[Blank-Disk]

I've been having major hesitation and idle speed issues for the past couple months. I just ran a diagnostic on my 93 ATX, and the code I really didn't want to see came up.

542 (O,M) Fuel pump open, bad ground or always on - - Power / Fuel Pump Circuits

The fuel pump runs, and it sounds good. I had it replaced when I bought the car 2 years ago. I just replaced the fuel filter, and it didn't help much, as the filter was replaced with the pump. Something I've noticed though, is that it doesn't turn on when I turn the key to 'on' like so many guides say it will do (am i reading this wrong). It only starts when the engine does. It would DEFFINATLY explain the troubles I've been having, but the pump sounds good when it's running. Also, my gas milage is fairly normal, maybe just a bit low for this area, but nothing to really get in a huff over. For a while though, it was going about 15mpg, now it's at about 20mpg. The imcredible loss of power I'm getting is agrivating to say the least. I can barely keep up with traffic at a green light.

Could this be an electrical issue? SHoudl i get a new pump? Or should fly back to NY and **** the first and last mechanic this car ever knew under my watch?

 

[Ishodu]

Usually a 542 code is just ignored. It will pop up anytime the car stalls or turns off with out the key being turned off. Is the car up to par on the rest of its maintenance? Whens the last time it had a 60K? Oil in plug wells? Old plugs and or wires?

 

[Blank-Disk]

Interesting follwoup to this. I did soem reading and figured I'd check the impact shutoff switch. i was pressed in, but jsut to make sure, I wanted to trip it,a dn then reset it. After pouding it (and hearing a clickign sound) about 7 times, the button finnaly came all teh way up. The engine slowly cmae ot a stall. I pushed it back in, and turned went to go star it back up. Like a needle in the ***, it fired up, and I have NEVER seen it start up that fast in the 2 years I've owned it.

Thrilled that the problem may be solved, i jump in, and take off. Going good, going good, hesitation, ARG! It hesitated just like always. WTF?! Also, I was mistaken, it has ben priming when i turn the key to ON, for some reason I just never heard it. But still, it's acting liek crap.

 

[Blank-Disk]

i jsut did a 60k and had the trany rebuilt a few montswh ago. So that's not the problem for sure. This has GOT to be the fuel pump or something close.

 

[Sho-N-Go]

If you dont take time to listen to others. They will quit helping you. I would check plug wires, oil in plugwells, TP sensor any of these problems will not throw a code. Even if you were just in there doesnt mean something isnt right. what is your fuel pressure? Do you have plugged cats? has is been this way since the 60 k was done? We need more info.

 

[Blank-Disk]

I checked the plug wells and they're fine, and since the cylinder blanace test went off without a htich, that tells me that all the sparking is going fine. I reset the comptuer about 2 weks ago, so this code 542 means that it happened recently, and with all the problems I've been having, i'm not about to ignore it. This started happening about a montha nd a half ago. This of course, was after I drove it 2,100 miles from NY to NM. After the 60k, the engine has been great, plus I had the tranny rebuilt, so driveleine wise the car is doing awesome. I ran codes after my long drive to see if anything came up and nothing did, so this code is new. Remember, it's an ATX, it doesn't stall all that often. In fact, it's never stalled on me unintentionaly.

I just took the car out for a spin, and it feels like it's got very little pressure in the lines. It also doesn't accel at a constant rate, it jumps and lags randomly. What kind of pressure should I be looking for? Also, what electrical connections should I be checking, and where are they? This pump is only 2 years old, and sat for a year and a half while I was saving up to fix the tranny. I'd really hate to replace it.

 

[wood_e]

Maybe your fuel filter is old and needs replacing since the car sa for so long, or maybe you have some bad gas.. Thats a cheap thing to repalce to see if you can get any extra pressure. As for pressure readings search for fuel pressure and you should find the correct readings...

 

[Blank-Disk]

Maybe your fuel filter is old and needs replacing since the car sa for so long, or maybe you have some bad gas..

the first thing i tried was the fuel filter, and it didn't help any. Also, the problem has been going on long enough that gas type isn't a concern. When I swapped the filters, i looked at the gas in my catch pan, and it was fine from both the tank and engine lines. Judging from my crappy performance, i'm still leaning toward electrical problems.

 

[Blank-Disk]

okay, i just got the psi, and it was steady at 35psi and went to about 40psi when i reved it. after 5 primes it was at 40psi also. i noticed that when i released the pressure through the relief hose ont eh tester, there's were a TON of air gaps inside, could this mean soemthing? any thoughts?