Engine will not start after upgrades**help**

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Denali_high

Newbie
Joined
Jul 8, 2017
Messages
15
Reaction score
2
Location
Champaign Illinois
Ok so here my issue... I bought this truck about 6 months ago and did extensive work to it including a stock motor swap..i drove it home from my friend's house and the driver side exhaust broke off at the down pipe. So I got it home and started to do some bolt ons that would make a custom tune worth while.

I installed longtune headers and replaces the upstream 02s

Egr block offs from route66mods

Ebay air intake,silencer mod,throttle plate mod

Pulled and painted stock valve covers. While doing this i had to remove the alt bracket and loosen the AC and power steering bracket.

Accel high temp plug wires

Clutch fan delete for E fans

After i coated the longtubes I installed them and began to put everything back together.

Long story short.. it refuses to fire. Cranks but not starting at all.

Its getting fuel

Has new cap and rotor..new ign module..new crank and cam sensor.

Me and my friend did some electrical trouble shooting and everything checks out fine but there is no pulse from the coil.

Everything worked just fine till I started to do these mods.

A little history behind it all...

Bought the truck with no motor or wheels and needed a rear end swap. Got all that finished and come to find out the fuel pump relay was not getting a good connection (after we found out the fuel pump the previous owner installed was the wrong one)

Codes that showed up was the crank and cam sensor..but it fired everytime..while it was down I figured i would replace them all.. well now it keeps popping up the crank sensor even after clearing it..this is the 3rd sensor I've put on it so frankly its not the sensor itself.

We spliced the whole wire loom the other day and there is not a single wire. The crank sensor gets 12v or so w the key off..but as soon as the keys on it drops volts drastically. Is this normal?

Its sat for so long and there is NOTHING I can find wrong...all plugs are plugged in checked the fuses probably 2 dozen time's. This is starting to depress me like no other!

I have alot more to do to it but this is holding me back so far its not funny!!

Can someone please chime in? There hasnt been one person whos been a help that I've asked yet..

So I will use this as my first post on the forum. If this is the wrong place to ask then I guess I should find another forum. This was the closest topic I could find.

SOMEONE PLEASE HELP i don't know what to do at all
 
Last edited:

Denali_high

Newbie
Joined
Jul 8, 2017
Messages
15
Reaction score
2
Location
Champaign Illinois
A new coil is on its way. If this doesn't work ima seriously rage yank this 5.7 vortec out..sell it and do a 5.3-6.0 swap!!!

Nothing has helped at all..practically the whole ignition system has been replaced. Only got to drive it maybe 50 miles to park it..

Still doesnt explain why it keeps popping up crank sensor after being cleared and a 3rd sensor.
 

east302

I'm Awesome
Joined
Oct 4, 2013
Messages
3,413
Reaction score
3,131
Location
Jackson, MS
What code number(s) are you getting?

So you have no spark from coil (versus no spark from coil wire at distributor) correct?

*Do you have 12V to the coil? Pink wire.

*Are you getting a switching signal from the ICM when cranking? Use maybe a test light or rigged up noid light. Probe White/Black wire with other lead to B+.

If no signal from ICM, check for signal from the VCM. Probe the ICM connector (white wire) with other lead to B+ and see if you get the light to flash when cranking. If it flashes, it's a bad ICM. If it doesn't flash, then it's a bad VCM, CKP sensor or issue in the circuit.


You must be registered for see images attach





Sent from my iPhone using Tapatalk
 
Last edited:

Denali_high

Newbie
Joined
Jul 8, 2017
Messages
15
Reaction score
2
Location
Champaign Illinois
What code number(s) are you getting?

So you have no spark from coil (versus no spark from coil wire at distributor) correct?

*Do you have 12V to the coil? Pink wire.

*Are you getting a switching signal from the ICM when cranking? Use maybe a test light or rigged up noid light. Probe White/Black wire with other lead to B+.

If no signal from ICM, check for signal from the VCM. Probe the ICM connector (white wire) with other lead to B+ and see if you get the light to flash when cranking. If it flashes, it's a bad ICM. If it doesn't flash, then it's a bad VCM, CKP sensor or issue in the circuit.


You must be registered for see images attach





Sent from my iPhone using Tapatalk
What code number(s) are you getting?

So you have no spark from coil (versus no spark from coil wire at distributor) correct?

*Do you have 12V to the coil? Pink wire.

*Are you getting a switching signal from the ICM when cranking? Use maybe a test light or rigged up noid light. Probe White/Black wire with other lead to B+.

If no signal from ICM, check for signal from the VCM. Probe the ICM connector (white wire) with other lead to B+ and see if you get the light to flash when cranking. If it flashes, it's a bad ICM. If it doesn't flash, then it's a bad VCM, CKP sensor or issue in the circuit.


You must be registered for see images attach





Sent from my iPhone using Tapatalk

My friend is supposed to come help me today. I will have the code numbers and all these steps gone over today...Im pretty sure we have done all this tho.
 

Denali_high

Newbie
Joined
Jul 8, 2017
Messages
15
Reaction score
2
Location
Champaign Illinois
What code number(s) are you getting?

So you have no spark from coil (versus no spark from coil wire at distributor) correct?

*Do you have 12V to the coil? Pink wire.

*Are you getting a switching signal from the ICM when cranking? Use maybe a test light or rigged up noid light. Probe White/Black wire with other lead to B+.

If no signal from ICM, check for signal from the VCM. Probe the ICM connector (white wire) with other lead to B+ and see if you get the light to flash when cranking. If it flashes, it's a bad ICM. If it doesn't flash, then it's a bad VCM, CKP sensor or issue in the circuit.


You must be registered for see images attach





Sent from my iPhone using Tapatalk

P0336 is the code.

We did the test again.. no pulse
 

TravisR

OBS Enthusiast
Joined
Jan 3, 2017
Messages
72
Reaction score
31
Location
Arkansas
*Do you have 12V to the coil? Pink wire.

New coil installed. Still no luck

With the new coil, I would make sure you have power going to the coil. A new coil won't send power to the distributor if it's not getting power to itself.

This might be frustrating, but another engine swap won't necessarily fix it. There's a reason why this engine isn't firing and it can be found with enough time and patience.
 
Top