LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Trouble Shooting the 396! Come Join!

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Old Nov 13, 2006 | 06:31 AM
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Okey guys,


After having some trouble with my builder, ive decided to take the car home, the project is about 80% done and ive got some work to do.

First off, the car has been started and has idled normal with the setup exatcly the same, or so i think. It has a baseline from alvin.

After installing the new trans and stall tonight, i decide to prep everything and fire it up.

First time, idle okey, then starts to fall and fall and finaly dies. that lasted about 20 seconds.

2nd time, starts idles and dies, about 4 seconds.

After both times the exhaust had a pretty nasty fuel smell to it.

At this point im just trying to go over the basics "Fuel, Air, Spark"

I have Fuel, new walbro, and i have a FPR and it was around 38, not sure if thats an acurate or not.

Spark, have new plugs gapped to perfection. Opit is a year old, dont think thats it, but possible.

Air, its breathing.

Also has open Headers, with heated O2s, Builder used 4wire o2s instead of the single wire........

Something i thought but have played a part in the killing was turning the crank hub manualy to get the conveter bolts in, i heard a pressure release everytime i turned it, not loud or long, but a slight hisss.

So at this point im stuck on what the problem could be.

Any Ideas Guys?

Tony.

Last edited by Speed Density; Nov 13, 2006 at 06:45 AM.
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Old Nov 13, 2006 | 07:19 AM
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mine did that when I was getting really bad knock retard, my serp belt was too big and the tensioner was making a knocking noise, do you hear anything that could be interpreted as knock? do you have a scanner so you can get a datalog?
Are you saying that it ran fine without the trans connected, then when you put the trans on it does this now?
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Old Nov 13, 2006 | 08:32 AM
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Will it idle if you crack the throttle blades a little?
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Old Nov 13, 2006 | 09:30 AM
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Has to be in the tune. Need to raise the idle steps a little.
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Old Nov 13, 2006 | 02:39 PM
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Trans was on the car when we started it. I didnt think it would be smart to start it up when the motor is only dangling by 2 motor mounts.

Forgot to mention that the 2nd time i started it up, I fed a little fuel through it, stayed alive but when it got up at 1300 the car seemed to choke.

Tony.
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Old Nov 13, 2006 | 03:13 PM
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Needs to be tuned. dont run it untill it is. Sounds like its fat, and that will wipe out the rings real quick.
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Old Nov 13, 2006 | 03:19 PM
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double check that your plug wires ain't crossed
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Old Nov 13, 2006 | 07:52 PM
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Well after talking to Dave it looks like im going to try and get the FPR set and hope that it will idle correct, once thats taken care of I can try and figure out what else might be holding me back.

Seems that even with a correct FPR it might have something to do with how the air is getting in the engine.


Tony.
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Old Nov 13, 2006 | 10:42 PM
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Did you put the donkey dick and the MAF and everything on. I know sounds basic but I've tried starting mine with it off (during opti change) and it just won't go.
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Old Nov 13, 2006 | 11:26 PM
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Its a Victor "E" Intake. And its Speed Density. No MAF.

Tony.
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Old Nov 14, 2006 | 02:40 AM
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Ok guys,

Just tried a couple things.

The car would die after a few seconds of starting before, so i decide to put a little folded up peice of paper on the throttle adj. screw, not a huge peice but one folde over a couple times.

It started and idled at 900, everything looked fine. The FPR was clocked at 45, and the vaccum hoes was on the reg too.

So i decide to pull the peice of paper, immediatly the car studders and dies.

So at this point i think ive found my problem, or at least one of them. I take the TB off and adjust the screw, its already less the 1/4 rotation maxed out, so i max it out to get the blades open more.

Put it on, try and start the car, and it starts then dies immediatly.

I do the paper thing againg, but now the car is just clicking realy loud, sounds like the starter, when i try and turn it over it clicks for as long as i hold it in ignition and the lights flicker.

So i let it sit for 10min or so, and go out and start it again, and same symptoms, starts dies.

I think it might be the battery too, since i have to wait for the bitch to build juice, and im wondering if the starter is worn. (Stock Starter)

What steps to take now fellas?

Tony.
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Old Nov 14, 2006 | 03:27 AM
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What's your idle speed set at? and what's the IAC counts? If it's unable to achieve the desired adle speed with the IAC alone then maybe you need to help it by drilling an idle bypass hole in your TB.
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Old Nov 14, 2006 | 09:22 AM
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my stock motor did this when my battery died put a new battery in and everything was fine dunno guess the electronics take alot of juice to make them work properly
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Old Nov 14, 2006 | 10:28 AM
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Originally Posted by Speed Density
Its a Victor "E" Intake. And its Speed Density. No MAF.

Tony.
OK didn't know the mods, my bad.
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Old Nov 14, 2006 | 04:13 PM
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Might be getting a new battery then.

Tony.
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Old Nov 14, 2006 | 05:44 PM
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Get a new battery, have the alternator checked. Might not be charging enough for it to idle that low, and the battery is too dead.

If that doesn't fix it, check the TPS and the IAC. Also, you can always bend the throttle bracket a bit to add more idle since the screw is maxed. Can you put in a different longer screw?
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Old Nov 14, 2006 | 06:29 PM
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Guys,

Got a new battery and started on the firts crank. Good news eh.

So now im working with the Idle, I have kind of got it down, it starts and hits about 1150-1200 then in a couple seconds drops to 950-1050 and holds until it gets throttle, then it does the same thing 1150 and drops back to idle, the car on idle will also jump sometimes to 1200, its like its getting throttle but its not, and then it drops to normal.

FPR is holding at around 42 when car is at idle.

Here is what im concerned about right now....





Im getting this out of the intake and TB, the amount depends on how long the car is running. Im thinking its all the new parts, and coatings burning off, the smoke has no smell (or non that i can smell), and its happening everytime the car is run.

And remeber its a single plane, the intake was sand blasted too.

Any ideas?
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Old Nov 14, 2006 | 08:08 PM
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Bumpity.

Tony.
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Old Nov 14, 2006 | 08:40 PM
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looks to be hot oil vapor from the oil valley.
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Old Nov 15, 2006 | 02:10 PM
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ITs possible, i have a staright line breather from the Valve Cover to the TB.

Tony.
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