Hi guys,

I bought SC400 (92) and I have problem with Fuel pressure regulator. I bought LS400 for parts, but engine pheripherials are totally different...

I would buy new, but I donīt know specification of FPR for my SC400...

I am looking for more informations, but we have workshop only for LS400.

Please, can you help me with my issue?

Thanks .

 

Welcome to CL, your thread has been moved to the performance/maintanance section.
please try and post in the proper subforum in the future.

What is wrong with your motor or what are you experiencing, as it could likely be something else.
The fpr is not known to fail generally speaking, but the fuel pump ecu and the coilpacks are both known to fail quite often on sc400's. Perhaps tell us your symptoms and we can help you out.
The FPR should be relatively similar or even the same between an LS400 and a SC400.

 

Hi, thank you .

Yes, I found there some informations and our problem could be in fuel pump.

I will try LS400 or Walbro fuel pump.

We could try another coilpacks....

EDIT:

When Im driving on "Normal" mode on tranny, I cannot go over 3500RPM, when I switch to power mode, in a few seconds I cannot go over 2500-2750RPM. To this "limit" of REV is everything OK. I have on stock injectors, fuel rail, FPR and Fuel damper. I dont changed the fuel pump, ( I dont have another ). Last owner has cutted fuel filter and put here only hose ( so I thuink that there is problem with injectors, so I changed then ). Tommorow I will try if there is the same fuel pump like UCF20 LS400 and I will try to change the fuel pump, but if it doesnt help, I dont know what more to do. No MIL light, everything seems OK, just on this RPMs it looks like "fuel cut", just go 100rpms lower and everything is OK. I have no workhosp manual to check fuel pressure, does anybody know how to check the fuel pump pressure?

 

Try this when you get a chance..

https://www.clublexus.com/forums/per...tures-faq.html

 

probably not the pump. could be the fuel ecu but usually that give a no start condition, may be worth a quick test but I don't like to leave the 12v mod on all the time.
could also be the stock ecu going bad, perhaps open it up and look for leaky capacitors.

check both coilpacks, disconnect one at a time and see if there is a change, it should change when disconnecting and not run very well. If there is no change then that coil is bad.

 

Had a issue one time where i changed the pump.. it ran a little better but still like crap and would just shut off after like 20min of driving.. Ended up being the fuel ecu...