Chevy S-10 4.3 to 5.7 build Ver 2.0
#51
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I still have a little bit of engine tuning to do. For some reason, my LTFT'* are around 15-20 at idle(lean) but level out around 0 during driving like its suppose to.
Umm, trying to think of what other little odds and ends that still need to be done. Right now, its street driveable. Oh, I need to find an engine oil cooler that has 1/2" fittings so I can tie into my oil lines. Oh, for some reason, (one issue after another) my front differential won't lock in when I go into 4HI. But, I have time to play with that. Other than that, its done.
Umm, trying to think of what other little odds and ends that still need to be done. Right now, its street driveable. Oh, I need to find an engine oil cooler that has 1/2" fittings so I can tie into my oil lines. Oh, for some reason, (one issue after another) my front differential won't lock in when I go into 4HI. But, I have time to play with that. Other than that, its done.
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#52
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whats your fuel pressure should be about 58 koeo and go up to about 63-65 to run right. maf should be 5-7gms at idle and go up. did you replace cap/rotor/plugs/wires?
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Yes, I replaced cap/rotor/wires/plugs. All gaskets are new. I think I may have found the leak around my EGR or the plug for the EGR tube. Hard to tell considering they are pretty close to each other. (I used water to test for vac leaks)
If it was fuel pump, wouldn't I have issues under load instead? Even if the pressure was low, it shouldn't cause it to go lean at idle.
If it was fuel pump, wouldn't I have issues under load instead? Even if the pressure was low, it shouldn't cause it to go lean at idle.
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#54
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Mike,
Great write up- thread is a fun read.
On the fuel pump, one very remote possibility is the fuel pump ground wire is frayed. The frayed wire causes problems as start up and idle, not while driving. The ground is located on the rear left side of the bed, ties into the ground for the rear tail lights. I doubt you have a frayed wire, but i have seen two of them cause fuel delivery issues at start-up and idle.
Great write up- thread is a fun read.
On the fuel pump, one very remote possibility is the fuel pump ground wire is frayed. The frayed wire causes problems as start up and idle, not while driving. The ground is located on the rear left side of the bed, ties into the ground for the rear tail lights. I doubt you have a frayed wire, but i have seen two of them cause fuel delivery issues at start-up and idle.
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I don't know about the wire, but I do know the pump was replaced just a couple years ago. (I got a few reciepts from the previous owner)
You may have fun reading this, but I'm not going to recommend this project to anyone. LOL.
You may have fun reading this, but I'm not going to recommend this project to anyone. LOL.
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#56
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this engine is so fuel critical, fuel pressure is always the first thing i check. lots to go wrong and make it run poorly. you better bet comfy with your gauge. i thought about getting some kind of electronic pressure sender so i could put a gauge permanently mounted in the cab
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I remember checking it last week for ***** and giggles. I seen it was in the high 50'*-60'* area. But, I'll check it again when I get home tonight.
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#58
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The pressure gauge will spike up to like 65psi, then drop to 60psi once it stops priming and hold. I replaced the filter(which didn't seem that old) and still have the same pressure.
Engine running, it sits at 59psi. If I goose it, it goes 65 and further for a split second.
Engine running, it sits at 59psi. If I goose it, it goes 65 and further for a split second.
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Yea I think I did. The bolt didn't seem to be threaded in all the way. So I doubled up on EGR gaskets. LTFT'* are now 8 and 6 at idle. I should be able to tune those out.
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