Is it running right?
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Freshman User
Joined: Aug 2003
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From: The Shakey State
Is it running right?
I just finished rebuilding a 5.8L, crank is 10-10, bore is 30 over it has teflon pistion skirts, a RV cam slightly longer durationa and lift.
BUT it seams like it is starving for fuel. I have cleaned and replace the injectors, sensors, ETC. BUT it still runs Lean?
Ive taken plugs 5, 6, &7 out; 6 is off white, but 5 & 7' porcelain is as white as snow. I've taken it to a local garage and they can't find anything wrong. What's your thought?
Here is the symptom; the engine slightly shakes or flutters as it idles, when driving and you jump on it it goes but seams like there is not enought fuel, when you listen to the exhaust it makes a funny sound alsmost like it is sucking air in but not at a regular interval, and it is burning alot of fuel.
What should I check, it seams that the garages can't diagnose problems if the computer doesn't tell them what to look for.
B4 the engine blew, that battery died, on replacement the alternator burnup when I started it, and the next day the starter did the same...what about the computer? How can you check to see if it is working right?
Thanks
Herc 5HP
BUT it seams like it is starving for fuel. I have cleaned and replace the injectors, sensors, ETC. BUT it still runs Lean?
Ive taken plugs 5, 6, &7 out; 6 is off white, but 5 & 7' porcelain is as white as snow. I've taken it to a local garage and they can't find anything wrong. What's your thought?
Here is the symptom; the engine slightly shakes or flutters as it idles, when driving and you jump on it it goes but seams like there is not enought fuel, when you listen to the exhaust it makes a funny sound alsmost like it is sucking air in but not at a regular interval, and it is burning alot of fuel.
What should I check, it seams that the garages can't diagnose problems if the computer doesn't tell them what to look for.
B4 the engine blew, that battery died, on replacement the alternator burnup when I started it, and the next day the starter did the same...what about the computer? How can you check to see if it is working right?
Thanks
Herc 5HP
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Joined: Jul 2003
Posts: 1,486
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From: Independence, MO
If your timming and everything else is in check, then check your fuel presure then instal a adjustable fuel presure regulator and raise the fuel presure by 10 psi and see if it performs better. when you bored the block you added cubic inchs, and with a bigger cam your putting in more air, now you have to have more gas, the computer will not compensate for this on its own, you can do this by raising the fuel pres. and/or reprogramming the ECM, or a performance chip. hope this helps. DW
Thread Starter
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Freshman User
Joined: Aug 2003
Posts: 27
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From: The Shakey State
Thanks, I had not figured that part out yet. I did notice that it ran better on the cold idle, so that makes great sence. The timing is at 13 BTDC, it runs better there, but I never heard it ping.
The fuel regulator is on the injector fuel line, where would I best find an adjustable one?
Thanks
Herc 5HP
The fuel regulator is on the injector fuel line, where would I best find an adjustable one?
Thanks
Herc 5HP
Posting Guru
Joined: Jul 2003
Posts: 1,486
Likes: 0
From: Independence, MO
My regulator is a holley unit you can get at summit racing for about $50-$60 bucks or you can go with a Billet Aluminum one for around $100+. But thats why it runs better when its cold, when the engine and air temp are cold the ECM richens the fuel mixture and advances the timming, but as it gets warmer it starts cutting them back to prevent ping/sparkknock. A little tweaking and experimenting here and there, you'll get it better. Good Luck DW
