code 542

[metallicademon1]

I have a 94 that I bought from the junk yard. I also have all of the dealer manuals on this car, and have not found the problem. It runs, but runs at about 2000 rpm's and if I give it a good shot to about 5000 rpm's it will go down to about 1000 rpms. It is throwing the code of 542. It says it could be a open in the fpm splice, ok, well where is that at? I have actually found diagrams on here that contradict what my dealer manual says. Anyone ever had this problem? Thanks.

 

[Sapperfire]

People still listen to Metallica?

 

[97 Octane]

Sounds like you need to replace the fuel pump!


Code 542 is a fuel pump secondary circuit failure.
Check to make sure you are getting about 30-40 psi fuel pressure.

Another cause may be a bad high speed fuel pump relay.
Check the relay, located on the driverside fuse box, in the engine compartment.
You will see a row of relays. The high speed fuel pump relay is the one closest towards the headlight. You can do a relay bypass test by jumping pin #30 with pin #87.

Another issue could be a bad VCRM, which controls the current going to the fuel pump.


-Ren

 

[mistermaclincoln]

I got that code also and I didn't believe it because I just installed a new one about a year ago and I check the pressure and I had good pressure. Check out my thread on Poor Performance and I bet you will find something in it to help you.

 

[chris2523]

I got that code also and I didn't believe it because I just installed a new one about a year ago

meh. new stuff goes bad all the time. new does not mean good. no no no.

I check the pressure and I had good pressure.

this means that its good. not how new that it is.

 

[metallicademon1]

More than they listen to you sapper...lol. I replaced the fuel pump, replaced the hfp relay, checked my ground on both ends going to the fuel pump, taken a jackhandle to the side of the car, and that still didn't fix it. The only thing I haven't done was check all the splices in the wiring harness, but i have checked a couple, with no avail. What would i do if i were an ase certified mechanic?

 

[slowmkviii]

When its at 2000 rpm
Give the iac a love tap
I have had a fuel pump secondary circuit failure code although i dont remember how i fixed it but it wasnt a fuel pump, vrcm, fpr or maf.