Need help!!!
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Need help!!!
I have a 93 lt1, when my car goes to close loop the engine stumbles. If I stay on the accelerator pass the hesitation the car takes off. Pump and fuel filter has been replaced. Coil is new and opti doesn't look like its malfunctioning. The injectors are not oem, they are yellow ford injectors #F4SE-A1B, 0 280 155 700. Keep in mind I bought the car used. Are the injectors to blame, I've read that the originals are at 22psi, and I should have around 36-40 psi at the rail. I hooked up my fuel pressure gauge and I get 34psi at the rail.
Any advise would be greatly appreciated.
Any advise would be greatly appreciated.
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Pull the vacuume line off the Fpr and smell for fuel. Pull the hose off the FPR and see if the pressure goes up. How old are the o2s? Did you use thermal grease on the ICM when your replaced the coil? Did you replace the sock and the pulsater with the proper hose when the pump was done?
Last edited by antfarmer2; May 9, 2016 at 10:05 AM.
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and yes the pressure goes up when I remove the vacuum line. from 34 to 44psi
Last edited by rpenajr4; May 9, 2016 at 10:05 AM.
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Drifting
Joined: May 2013
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From: Reno Nevada
The OEM injectors were Rochester Multec's and aren't that great. Your car needs a 24 lb injectors and the 0280-155-700 aren't even 20 lbs. Your ECM can't make up for the undersized injectors. Make sure to tell Martin this is for a TPI application. Get rid of the Bosch yellows.
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The OEM injectors were Rochester Multec's and aren't that great. Your car needs a 24 lb injectors and the 0280-155-700 aren't even 20 lbs. Your ECM can't make up for the undersized injectors. Make sure to tell Martin this is for a TPI application. Get rid of the Bosch yellows.
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I thought late c4s were 22 lbs till 94 they went to 24 lbs. Might be wrong but do some reseach.
Last edited by antfarmer2; May 9, 2016 at 10:38 AM.
Drifting
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From: Reno Nevada
I will say this: I have a loosely based L98 and in 2012 a friend sent me those and I installed them in mine at 48 psi. My 90 L98 programs at 22.1 and when I got my flowrate down to 19.8 my BLM's came within range. Keep in mind that they flow 204 cc rated at 43.5 and I had my pressure at 48. Therefore, your LT1 programmed at 24 lbs needs the one I posted above.
http://witchhunter.com/flowdatapix/b0280155700.jpg
http://witchhunter.com/flowdatapix/b0280155700.jpg
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I will say this: I have a loosely based L98 and in 2012 a friend sent me those and I installed them in mine at 48 psi. My 90 L98 programs at 22.1 and when I got my flowrate down to 19.8 my BLM's came within range. Keep in mind that they flow 204 cc rated at 43.5 and I had my pressure at 48. Therefore, your LT1 programmed at 24 lbs needs the one I posted above.
http://witchhunter.com/flowdatapix/b0280155700.jpg
http://witchhunter.com/flowdatapix/b0280155700.jpg
24lb Bosch 3 for TPI
Product Code: NEW2HJW987
New in Box 24lb Bosch EV1
24lb or 252cc/min Rated Flow
High Impedance for use with stock computers
60mm O-Ring to O-Ring
would that do?
Last edited by rpenajr4; May 9, 2016 at 10:47 AM.
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Drifting
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Order them from martin and you'll have them in 2 or 3 days. Autoparts will drill you hard on pricing.
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OP - This car apparently ran fine at the point when you purchased it. Correct? I ain't gonna' debate the injector issue but what have you changed since purchase?
How long ago did you buy? Time and miles? From someone you know? If yes maybe you get the PO to do a warranty of the injectors from "whomever".
Things changed since purchase if it ran well I believe need the first look!!
How long ago did you buy? Time and miles? From someone you know? If yes maybe you get the PO to do a warranty of the injectors from "whomever".
Things changed since purchase if it ran well I believe need the first look!!
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OP - This car apparently ran fine at the point when you purchased it. Correct? I ain't gonna' debate the injector issue but what have you changed since purchase?
How long ago did you buy? Time and miles? From someone you know? If yes maybe you get the PO to do a warranty of the injectors from "whomever".
Things changed since purchase if it ran well I believe need the first look!!
How long ago did you buy? Time and miles? From someone you know? If yes maybe you get the PO to do a warranty of the injectors from "whomever".
Things changed since purchase if it ran well I believe need the first look!!
Tune up - plugs,wires,coil, and fuel filter.
Then the pump and fpr.
Yes the car has felt like this from day 1, just didn't realize that it would act like this only during close loop
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I tried ruling out a lot parts, don't want to just replace and still have the same issues. I hooked up my scanner I see the o2's on both banks to move gradually from 0mv to 800mv, my tps has a .58v at rest and only goes to 3.18 at wot, I have to practically put a hole on the floor board to get 4volts.
So then I pulled the rail because when I saw the yellow injectors at first glance I knew they weren't stock but wanted to check everything else before reaching to the injector conclusion.
So now I pretty much have the incorrect lbs of injectors for my lt1. Could this be the culprit, some of the other guys have recommended a set of injectors, which I'm a few clicks away from placing order.
Last edited by rpenajr4; May 9, 2016 at 04:52 PM. Reason: Needed more explaining