ly6 swap- having start issue

[xsboost90]

so i have an LY6, mast cam,LS3 intake, DBW,55lb inj, custom harness and tune in place. Started the car a few weeks back with no maf or o2 sensors and it fired right up but wouldnt idle very well, obviously. Got the intake on there with the maf hooked up and installed the o2 sensors. Tried to start the car and it fired right up but started backfiring- which it had a few times before as well. I shut it off and started researching and found it looks like the plugs on the small harness for my PS coil packs was installed backwards after repainting stuff. Swapped that around and tried to start it..nothing. Checked- all eight plugs totally soaked with gas. I pulled them and replaced them with some new a/c delco irridium plugs and tried again= nothing. I did get one good back fire then nothing. Plugs are soaked again. Checked fuses- all good, cant find anything else...tried unplugging the maf to see if something was going on with that- still nothing. Guess i need a scan tool but any ideas?

[xsboost90]

checked fuel pressure- 58psi- checked injector driver- pulsing as you crank. Unplugged all injectors to crank and hit it with start fluid and its popping back through the intake! Not sure why this is happening it seemed to run ok the first few times it started up. Its like the timing is way out.

[andrewb70]

Sounds like there is no spark. Did you reinstall the two big ground wires to the back of the heads?

Andrew

[xsboost90]

i have a number four ground from each head to the frame. ground for the swap harness in a couple spots. The noid light on the injectors harness shows pulsing so the crank sensor
is good right?

[gordonquixote]

I saw a very similar issue on Kindigit Designs and the problem was the pins in the MAF plug were reversed. HE pushed the out, put them in the right place, and fired it right up.

[xsboost90]

hm- well this started up with the maf unplugged and would run a second then shut off. Now it just cranks. Im seeing spark but its almost like its not in time or something. It will crank and crank, cough alittle then nothing. Fuses are ok, only thing i did was plug in the o2 sensors and maf- tried unplugging them but nothing still. Not sure if it could have slipped timing? Seems unlikely.

[andrewb70]

Cam sensor plugged in?

Andrew

[xsboost90]

just checked the one in the front bottom by the pan. That one is good- Perhaps when i put the o2s in i knocked one loose- or something.

[xsboost90]

checked cam and crank sensor- both plugged in- unplugged then replugged- still no fire. When i pull a wire and test for spark, it has it but its weak. Maybe battery is just alittle too low now?

[willieboy240]

Who made the harness ? Are you sure it is all pinned correctly for your motor ?

[xsboost90]

Bp-automotive - this fired up and ran fine the after installing the maf and o2 sensors it won't start.

[csouth]

Bp-automotive - this fired up and ran fine the after installing the maf and o2 sensors it won't start.

you need to scan and see if you have any error codes. Right now you're shooting in the dark.

[xsboost90]

yeah im waiting till wed. a friend is bringing his HP tuner over to check the car out. Im also charging up the battery and checking over things. Weird. The car literally has started instantly every time i bump the starter but has some back fires etc. after running a few seconds. Finding the wires on the coil swapped was an aha moment and i thought ok this thing should be perfect now. Then nothing works. All the plugs fouled. Maybe i just ran the battery down too far but it was cranking pretty well. Either way some time on the scanner may clear some issues up for me.

On another note, working on a couple side jobs and when those leave i should have the cash to buy my full set of Speed Hut gauges, then the real fun begins....

[xsboost90]

133957133958well, my buddy came over and we scanned the car with Hp tuner and everything looked perfectly normal. Getting spark, getting fuel, getting air....cranking seemed alittle slow- tried jumping the battery and changing some connections. No dice. Read online that cam sensor could cause issues, bought a new one and when we pulled this one, it had scrapes on the back of it....

pulled valve cover and cranked the motor over- top end not moving! Pulled the whole front of the motor off and found that evidently i did not torque the big crazy vvt cam bolt down- or it didnt line up with the pin properly. Cam pulley came loose and was just spinning- and digging a rut in the back of the pulley with the pin from the cam. Didnt damage the cam, did mess up the pulley, cam sensor, and i'll need another one use cam and crank bolt. Couldn't find a cam pulley used for a decent price so im getting a new one just under $100 on line. Lesson learned- hopefully it didnt bend any valves with this....

[12sec ss]

I just took all the vvt stuff out of my 2014 escalade, let me know if you need any of it still

[xsboost90]

thanks- got the timing part all back together- now it has four bent intake valves to take care of..uhg.

[xsboost90]

ok so more issue somehow with this damn car. Got the new timing gear, looks awesome- installed the cam phaser limiter just as i had the other. Installing the gear is a pain because there is just one pin that it sits on and one big bolt- and the cam moves forward and back some so you have to pull the cam forward with a bolt and then drop it on the pin and chain at the same time, then put the bolt in. So i did this and put the bolt in and torqued to spec. Installed the front of the motor, pulled the heads and found four bent valves. Heads look fine so i dropped in four new intake valves and put them back on after prepping them and new head gaskets and head bolts. Torqued them per spec and put the motor all together. Gave the key a twist and she fired right up and sounded very good. It was running about 1800rpm and starting to drop to an idle then the motor just died again like someone shut off the key.

Tried to restart and it once again will not start. Checked the top end and yes the rockers are moving, none of the pushrods are bent etc. Decided to do a compression test to make sure i didnt somehow drop more valves. Tested Six cylinders that were easy to get to and got 0 psi on all six!!!!! Ok this makes no sense so i tested my comp. tester on something else and it worked fine. Retested a couple on the car and still showing no compression. SO i opened the throttle body and blew air into number 2 cylinder plug hole with the intake valve open-spring depressed - and air comes out the intake. Cranked it over so the valves are closed and retried blowing air into the spark plug hole and no air out the intake or exhaust, then pulled the nossle out of the hole and air rushes out like it hadnt gone anywhere else. (this cylinder just showed no compression!!) What am i missing here. THe car cranks over fine, doesnt appear to have bent the valves again although i only checked a couple of them this way but still no compression what gives. Crank the car and it coughs and shoots smoke out the top like maybe its out of time again- not sure how- i am about to pull all the vvt stuff out with my $600 Mast cam and go to a non vvt setup if i cant figure this out. Three bolts would be much easier....

[andrewb70]

Sounds like you bent the valves again. Are you sure that your combination has adequate piston to valve clearance?

Andrew

[71RS/SS396]

Sounds like you bent the valves again. Are you sure that your combination has adequate piston to valve clearance?

Andrew
I'm with Andrew on this.

[xsboost90]

Not when the cam gear keeps having issues. Guess I'll tear it all down again.

[xsboost90]

tore the front of the motor down last night and found the cam pin sheared off. Had spun only a few degrees and no valve contact! Cool i'll just pull the cam out and send it to the machine shop to get the pin out and put a new one in...well no the third cam bearing also spun and i cant get the cam out...FML

[xsboost90]

well dropped the motor off at the machine shop thursday morning and friday afternoon i get a call that they got the cam out, polished it and drilled the pin out- everything checked out ok and the new bearings were already in with some green loctite and some new rod bearings going in for good measure. Just need another new cam gear and a cam pin, then its coming home.

[xsboost90]

BIG thanks to 12sec-ss for hooking me up with a new cam gear and for MASTmotorsports for pointing me in the right direction to CAM Motion to get my cam pin. Called these guys and they are sending me a cam pin no charge! Hopefully the parts will be here and i can pick up the motor from the shop and get this thing back together even better than before and be running this year!

[BlackHD]

Good luck man!