split fuel trims, low rpm shaking
09-15-2012, 11:49 PM
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split fuel trims, low rpm shaking Hey everyone, now that im finally getting situated im hoping i will have some time to start working on ye ol lt1 before i park her for winter, rather figure out the solutions to the problems so i can start my next project this winter
Anyways i have my 96 z28 with a 6 speed, le2 heads and ported intake, xfi 280 cam, pacesetter race(no air/egr) long tubes, ac delete, not cats, no rear o2 sensors, no evap with 36 lb hr inj. Anyways fuel pump is going bad, have to prime the key several times before it will start on first try otherwise it just cranks until it gets enough fuel to start. While driving i have noticed in higher gears especially the car shakes like crazy (5 or 6 below like 1500 throttle to the floor) and it doesn't accelerate clean almost like constant miss, also using a basic live engine reading scanner i have split long term fuel trims, one bank reads really rich other reads really lean. also have like a high rpm miss like fuel is cutting off i cannot verify it is fuel though for i have not put a guage on it yet..... Should be ordering new racetronix unit soon though just need to get a little more situated, just need to know if this sounds fuel pump related or something else... both 02 sensors read well in short term fuel trims constantly changing also
thanks in advance
Anyways i have my 96 z28 with a 6 speed, le2 heads and ported intake, xfi 280 cam, pacesetter race(no air/egr) long tubes, ac delete, not cats, no rear o2 sensors, no evap with 36 lb hr inj. Anyways fuel pump is going bad, have to prime the key several times before it will start on first try otherwise it just cranks until it gets enough fuel to start. While driving i have noticed in higher gears especially the car shakes like crazy (5 or 6 below like 1500 throttle to the floor) and it doesn't accelerate clean almost like constant miss, also using a basic live engine reading scanner i have split long term fuel trims, one bank reads really rich other reads really lean. also have like a high rpm miss like fuel is cutting off i cannot verify it is fuel though for i have not put a guage on it yet..... Should be ordering new racetronix unit soon though just need to get a little more situated, just need to know if this sounds fuel pump related or something else... both 02 sensors read well in short term fuel trims constantly changing also
thanks in advance
09-18-2012, 01:23 PM
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yeah throttle body is a 58mm professional products, was going to look into fixing it i just wish i could get something to read gm parameters, like iiac counts and knock counts and those about, just wanted to know what everyones take on it, throttle body im definetley going to look into though
09-18-2012, 09:13 PM
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i understand what you mean about that, but the low rpm shaking has just started recently, i also believe it might just be the check valve don't know for sure, need to get a gauge on there just been so busy, probably ordering a new pump this week... maybe a new clutch also, split fuel trims i also don't feel like its pump related, maybe o2 sensors... who knows i gotta buy a new jack to lift the car up and take a look at those... some one jacked my 25$ jack... jokes on them though... it leaked haha
