LS6427

iTrader: (2)

But hell.....maybe if "LS1TA_956" is right and my crank broke.......it took out the sensor....

Can it take that sensor out?

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King Nothing

iTrader: (9)

i want to see your build thread on that engine!!!! and i hope everything works

LS6427

iTrader: (2)

Build thread on what engine???? You mean the 441ci rebuild if I need to do that???

My builder hand ports LS7 heads and LS7 intakes. Heads flow over 400cfm, but he's been busting his *** less and putting out heads that flow in the 395cfm range. He says that extra *** busting is a waste of time.
Lunati crank and rods
Wiseco pistons
11.3:1 cr
Cam will be 250's probably.
4L80E
102MM TB
No MAF
SD tune
Possibly a 200 shot....not sure.

Thats about it for the power info.

.

Time2Kill

iTrader: (49)

I had a stock Silverado SS that wouldn't start after sitting overnight. Ended up being a bad crank sensor that just died randomly with no other symptoms.

03EBZ06

run DTC check and also don't overlook a loose reluctor wheel on stroker cranks.

ls1 1990 VN

I broke a dual Rollmaster at speed while road racing, motor just shut down. Later while trying to fire it up, the engine spun over freely but wouldn't fire.

4 bent valves, 4 pistons with valve hit marks.

LS1TA_956

iTrader: (1)

Stop asumming stuff and get it checked it could be somthing as little as a relay or somthing big like crankshaft, and yeah ive seen forged cranks break. my buddys forged crank broke in 2 pcs and u could here then engine crank but the crank pulley wouldnt rotate.

If your not getting any signal from the crank sensor chances are its the sensor

Pull out the oil dip stick and wipe it with a clean paper towel and look for small shavings

Gl bud

King Nothing

iTrader: (9)

i'm sorry the build thread on the LS6 427

LS6427

iTrader: (2)

Yup, flying today to New York, be back tomorrow at noon. I'll check the crank sensor.

Im assuming if the flywheel is turning the back of the crank and the timing chain is moving as well as the crank pulley....crank is not broke.

Looked on the dipstick....no metal at all. We put it in and pulled it out a few times to check.

.

LS6427

iTrader: (2)

Built by the late "great" Dave Daluca at Agostino Racing Engines in 2002.

Manley rods
Ross pistons
Cola Crank
11.3:1 cr
Built it for a 200 shot. NEVER sprayed though. 173,000 miles N/A, daily driven.
Everything else is in my sig for top end........

.

LS6427

iTrader: (2)

Chain is moving for sure. Guess a leakdown check would tell if anything is bent.

But there's absolutely zero tapping noises so I doubt anything hit the pistons.

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joecar

Ok, so far you have what:
- injectors are firing (you hear them ticking, right...?)
- no spark, right...?
- no rpm on scantool, right...?

When you look down the oil fill hole on the valve cover do you see that rocker move...?

With a DMM do you see AC voltage signal when you backprobe the the crank sensor and cam sensor connectors (you will need a wiring diagram to see which wire)...?

(yeah the cam sensor connector may be hard to reach...)

LS6427

iTrader: (2)

Bold answers

- injectors are firing (you hear them ticking, right...?) have raw wet fuel in 4 cylinders after cranking. Never listened for ticking though
- no spark, right...? correct
- no rpm on scantool, right...? correct, zero rpm

when you look down the oil fill hole on the valve cover do you see that rocker move...?
yes, rocker moves

with a dmm do you see ac voltage signal when you backprobe the the crank sensor and cam sensor connectors (you will need a wiring diagram to see which wire)...? did not do this. But my friend said everything else he could see with the obdii scanner looked normal

****I'm just concerned about the weird cranking sound.......in the VID I posted.


.

joecar

raw wet fuel could be a leaky injector, which could prevent starting.

OBDII scanner is not sufficient.

Weird sound... this is bad.

LS6427

iTrader: (2)

No.....all 4 cylinders where I removed spark plugs to check them (2 on each side)......I stuck a long q-tip in each hole after cranking it to see if they were getting fuel. They are. Q-tips came back wet with fuel So we know the injectors are working.

Its not a tapping or knocking sound........its just a spot that slows the starter for a split second.

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lt1pwr1

iTrader: (1)

You are 100% sure you don't have spark? Because I've heard quite a few 2.2L Ecotecs with "jumped" timing chains (common problem) and your motor sounds exactly like those. You can hear the compression, then you can hear it lose compression. Hopefully it's a simple crank sensor though

LS6427

iTrader: (2)

Oh yeah, my friend came over and checked 4 cylinders. 2 on each side. Checked for spark while cranking in each of the 4 wires while they were attached to the coils.

All I know is....the rocker you can see through the oil fill neck....is moving while cranking.

Whats a jumped chain....what does it do in there? I almost positive I have a double roller chain.
How do I check for a jumped chain????............If there was spark, and a jumped chain, wouldn't the one cylinder that makes compression at least try to fire and keep going. There's zero sound of the engine trying.

.

Starkey

change the gd crank sensor already! if it doesn't fix it, take it back to Autozone.

You're getting fuel.

Rockers are moving.

No spark.

Just replace the crankshaft position sensor and roll on.

I'm gonna **** a lot of people off here, but I think it needs to be said.

Some of these internet mechanics think way too much. Test this.. get a scanner.. no, obdII isn't good enough, your fuel injectors are leaking, blah blah blah.. People, if he's getting no spark, the only LOGICAL thing to do is replace the crankshaft sensor. They fail randomly.

My advice, from a man who's fixed all types of vehicles during his life with a set of craftsman tools and logical reasoning, change the crankshaft sensor, get a new set of plugs, and start the damn thing up and see how she sounds.

ddnspider

iTrader: (26)

Was this not a clue?


Sounds like you're on the right track.

pewter2002

iTrader: (4)

LS6427 has tirelessly provided info on topics he is very familiar with. He has repeated his cooling system upgrade/advice/maint advice many times, same with power steering coolers etc. Without being confrontational or snarky.
I hope he receives the same constructive courteous advice now that he needs it.
GL with this issue, I am learning quite a bit here from the advice, there is a lot of knowledge in this forum!