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Forum nameTurbo/Nitrous Tech
Topic subjectInline Fuel Pump Causing extra Fuel Pressure = Rich?
Topic URLhttp://forums.2gnt.com/dcboard.php?az=show_topic&forum=8&topic_id=78560
78560, Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by HadesOmega, Dec-31-69 06:00 PM
Just wondering it been bugging me a while, for some reason my car runs rich, rich enough to not pass smog and have black deposits on my bumper and tailpipe. I took the turbo off of the car and still running the err.. stock star fuel setup. Mine has an inline pump instead of a intank. Is it possible that the pump making my mixture rich since it pumps so much fuel. I always thought that the fuel pressure regulator takes car of the extra pressure and since my car doesn't boost the FMU doesn't increase the fuel pressure. Could my fuel pressure regulator be bad or something. I was running some pretty high fp O_o
78563, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by azdave, Dec-31-69 06:00 PM
Make sure your fuel pressure is correct.

This happened recently on my truck. I installed a new Bosch pump when the original pump failed. The truck then ran extremely rich at all times. I checked fuel pressure and found 85psi when it should have been 35-39 psi. The fuel pressure regulator was bad (it wasn't bypassing the excess fuel back to the tank)and after changing it out all is back to normal.
78564, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by DarKReaLity, Dec-31-69 06:00 PM
yeah if you still have your FMU that's more likely your problem. you have no way of adjusting fuel pressures other than factory set. it also depends the size injectors you have now. damn dude it's been awhile you posted how have you been?
78565, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by ner947, Dec-31-69 06:00 PM
There's also a chance that the return line isn't big enough. If there is a flow resistance in the return like it will cause the pressure in the rail to go up.
78570, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by Ducking_Fumbass, Dec-31-69 06:00 PM
Try looking for kinks in the return line. That'll drive up your FP.
78872, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by HadesOmega, Dec-31-69 06:00 PM
Yeah I'm still Iraq, I went home on leave and was working on my car a bit and notice there's black smoke still coming out of my exhuast and my tail pipe is all sooty.

Maybe I should just go ahead and install that SFMU I bought on ebay a while back. Where's a good place to get a fuel pressure gauge for the engine bay, one that actually reads high pressures O_o
78873, RE: Inline Fuel Pump Causing extra Fuel Pressure = Rich?
Posted by MetalJim, Dec-31-69 06:00 PM
You can get them from Jegs or Summit pretty cheap. Every once in a while I'll see a Mopar one on ebay - http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33674&item=7931997955&rd=1&ssPageName=WDVW


95 Eclipse RS : 5 speed
15.7 @ 87.9mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html
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