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Old November 16th, 2010, 15:46
oldskoolsleeper oldskoolsleeper is offline
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87 renix 2.5 - high fuel pressure, is that bad?

Hey everybody, about a month ago I replaced my fuel pump and the jeep didn't run right. I went through everything and even adjusted the fuel presure regulator up as much as possible and still only had 8 lbs.

Took it to a shop and of course the hose wasn't tight enough on the fuel pump so that was fixed and it read 18 lbs.

The factory setting is 14.5 lbs. Am I running rich or am I worried for no reason?
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Old November 16th, 2010, 16:57
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kastein kastein is offline
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Re: 87 renix 2.5 - high fuel pressure, is that bad?

I'd adjust it back down to 14-15 if you can, else, wouldn't worry about it. Might just be me though.
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Old November 16th, 2010, 17:04
oldskoolsleeper oldskoolsleeper is offline
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Re: 87 renix 2.5 - high fuel pressure, is that bad?

Yea I've gotplans to turn in back down tomorrow, more curious really if it affects the amount of fuel sprayed because I feel like my mpg has decreased a litte bit.
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Old November 16th, 2010, 17:07
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kastein kastein is offline
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Re: 87 renix 2.5 - high fuel pressure, is that bad?

Theoretically it doesn't since the engine computer watches the O2 sensor to figure out if it needs more or less fuel, but the faster the injector flows fuel, the less granularity the engine computer has to control how much is used (since it pretty much just says how long the injector should be open for, and can only adjust the open period by certain "ticks", not sure how long each "tick" is though.)

Believe it will decrease fuel economy during warm-up (i.e. until the engine goes into closed loop mode when the temp gets to 170-180 or so) but I'm not sure, 4 cylinder TBI RENIX rigs are pretty foreign to me. And in a well maintained engine it will only take a few minutes for coolant temps to reach that range anyways.
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My yard looks like Sanford & Sons.
Please do not PM me about the AW4 info thread unless you have a truly unique question that is not covered by it or info to add. I do not respond to questions answered by the thread.
Definitely do not hunt down my phone number at 3AM, text me about it, and then threaten violence when I am not helpful. It will not get you what you want.
CTeunuch: Sometimes I really wonder if this sport makes you insane, or it just attracts the mentally unstable.
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