BRAD D Posted July 18, 2003 Share Posted July 18, 2003 Ok I tuned in my SDS and the car was going fine & hitting HARD. Then the car started running lean, added fuel and still lean no mater how much fuel I add it is still lean @ 0-psi and 1000-2000RPM I had the MAP fuel at that spot rich like crazy and still lean. Checked my fuel filter and it is fine, I have a 700HP Aeromotive fuel pump and the fuel is dumping out like a fire hose. so I think it is my regulator but I dont have my fuel pressure gauge hooked up so I cant tell. Oh how I want to feel the rath of the RB26 again please help any ideas Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted July 18, 2003 Share Posted July 18, 2003 You are probably right. Only way to know for sure is to measure the fuel pressure. How much base pressure were you running with the Aeromotive anyway? Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 18, 2003 Author Share Posted July 18, 2003 I dont know I was just letting it rip with 12 V 's hooked up to it,I wonder if that did it?? Thanks for the info Quote Link to comment Share on other sites More sharing options...
z-ya Posted July 18, 2003 Share Posted July 18, 2003 Get a couple feet of high pressure EFI fuel line. Put a gauge right before the regulator on the high pressure side. Position the gauge so you can see it from the drivers seat. The idle pressure should be around 38psi, and should increase as you accelerate. If it does, it's not the regulator. What duty cycle are you running the injectors? If you are at 100%, no matter how much you turn up the SDS, it will still run lean. Pete Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 18, 2003 Author Share Posted July 18, 2003 thanks for the help so far I will hook up a fuel pressure gauge tonight, I have RC 550cc injectors and the were running at 20-30% @ 1000-2000 rpm. It must be that reg... I have an autometer fuel pressure gauge I just have to tap into the rail. Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 19, 2003 Author Share Posted July 19, 2003 O.K, I tested the fuel regulator and it was showing 44psi @ idle or 15in of vacume and showing 50psi @ 0in of vacume when I reved it a bit. So I think the REG is fine, Then I tested the pump and it maxed out @ 92psi, so it is fine too. Now I am going to look at the injectors because when I unpluged on it still ran the same So now to check the Injectors...... Any tips?? Quote Link to comment Share on other sites More sharing options...
z-ya Posted July 19, 2003 Share Posted July 19, 2003 Just because you have pressure, doesn't mean you have flow. With the pump pumping into a gas can, do you get lots of gas flow? Check the flow right after the filter. Is there a filter before the pump (should be one to protect the pump)? Check that too. If that's OK, pull the injector plugs one at a time to find the suspect injector (aounds like you mignt have already done this). With the engine off, check the connections. Use an Ohm meter to verify that the injecor is good. It should read more than 2 Ohms across the terminals. Check the injector connector with an Ohm meter with it connected to the injector. It should again read more than 2 Ohms, but less than 15 Ohms (depending on your injectors). Hope this helps. Pete Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 19, 2003 Author Share Posted July 19, 2003 Lots of flow from the pump.And yes there is a filter before it... but not after it mind you I'm going to look at the injectors when I get up in the morning , I will also take off the fuel rail and look at the injector screens to see if the pump spit some thing out. Sorry for all the questions, but I would love to have it running like I did the first hour or two I had it out Quote Link to comment Share on other sites More sharing options...
Guest jt240z Posted July 19, 2003 Share Posted July 19, 2003 How do you know it's running lean? What are you using to verify this? Remember that a very rich condition along with a misfire will read lean on an AFM. Check your plugs to make sure that you are too lean. If the plugs are black, you could be compensating in the wrong direction. 15 in/hg at idle seems just a little bit to low but not to bad. Should be around 18 to 20 in/hg on a fresh engine. You may want to do a compression check just to make sure. 52psi base fuel pressure with 550cc injectors seems like a big overkill. Always check your base fuel pressure with the vacuum line to the regulator disconnected. What's the pressure with the line disconnected? Are you using an adjustable FPR? The stock FPR should give you 38psi with the line disconnected. I'm using an AEM adjustable and I've got mine set at 40psi using the 550cc RC's with no fuel delivery problems. It's all what base line you tune around. Quote Link to comment Share on other sites More sharing options...
stony Posted July 19, 2003 Share Posted July 19, 2003 hey brad another way you can check to see if its the injector or flow thru the injector is take a long screwdriver and listen to each injector. just place the screwdriver on the metal part of the injector and put it up to your ear. you should hear the clicking and all the injectors should sound the same. if they do not sound the same or one or 2 are not making any sound you have a bad injector. AIf they are all clicking the same you prabably got something thru the pump and clogged an injector. Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 19, 2003 Author Share Posted July 19, 2003 Thanks guys I think I found the problem (just got back from the dyno)..... Well we hooked up a wide band to the front and rear turbo, and the front bank was lean. so we switched the injectors from front to the rear and then the rear was lean, So the injectors must be pluged so I will have them cleaned and flow checked. the funny thing is I have new injectors, lines, pump & filter.... but the filter is a SS 100micron I guess i should use a 10micron paper one. Now I'm also running one infront of the pump just to be safe. Sorry no dyno results yet only had it up to 3300RPM or so..... next week we will see. Quote Link to comment Share on other sites More sharing options...
BRAD D Posted July 19, 2003 Author Share Posted July 19, 2003 Looks like you were right Stony, Thanks guys it should be up and running good in no time. 8) can't wait...... Quote Link to comment Share on other sites More sharing options...
stony Posted July 20, 2003 Share Posted July 20, 2003 yea thats cool.... the only reason i was thinking that was because mine did the same thing... was running great then out of no where it started running like crap. i checked everything and the injectors where my only options ;< having them flow checked cured the problem as they have to take the screens out to do it. mine flowed fine so the shop was like you have something else wrong wy dont you bring it by and let us "FIX" it. I said well now that i know the injectors are flowing fine ill install them and see how it runs. and walla ran like a champ. anyways good luck on the dyno. Quote Link to comment Share on other sites More sharing options...
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