93 454 TBI - no start after head gasket replacement

[SableSlayer]

Did you make sure that your distributor was dropped back in with cylinder 1 at tdc and not number 8 at tdc?

 

[termite]

OBDI. Not utilizing any scan tools

Numerous scan tools and laptop/phone apps that enable you to access the datastream on OBDI vehicles. I use tunerpro rt and a cable from the site below (first page that popped up, choose the cable that suits your equipment) . I have no affiliation with either.

http://aldlcable.com/products/aldlobd1u.asp

 

[Schurkey]

OBDI. Not utilizing any scan tools

Numerous scan tools and laptop/phone apps that enable you to access the datastream on OBDI vehicles.

Yup. Just get an OBD1-capable scan tool.

Did you make sure that your distributor was dropped back in with cylinder 1 at tdc and not number 8 at tdc?

#1 has #6 as it's companion cylinder, not #8.
1--8--4--3
6--5--7--2
1 & 6, 8 & 5, 4 & 7, 3 & 2.

Which is why 4 & 7, and 3 & 2 firing-order cam swaps are popular--the LS-series engines have both of those.

 

[scott2093]

I'll just put these here just in case...

88-98 Service Manuals

Over the years I have collected a bunch of GM service literature. Links to PDF Scans of service and STG manuals and a links to the Parts manuals. You'll need the FREE Adobe Acrobat reader to open these files. Get it directly from Adobe here {http://get.adobe.com/reader/} If you're not...

www.gmt400.com

a good read through this may be helpful as well

How To Test The GM Distributor Mounted Ignition Module

GM 4.3L, 5.0L, 5.7L Index of Articles

easyautodiagnostics.com

 

[SableSlayer]

Yup. Just get an OBD1-capable scan tool.


#1 has #6 as it's companion cylinder, not #8.
1--8--4--3
6--5--7--2
1 & 6, 8 & 5, 4 & 7, 3 & 2.

Which is why 4 & 7, and 3 & 2 firing-order cam swaps are popular--the LS-series engines have both of those.

Haha thanks! I know you know these motors a lot better than I do and thanks for all your in site.
Mine has put me through hell since I got it in 2020 but at this point I can change anything on it in a few hours time including heads and main bearings lol

 

[LOTW29]

Triple checked the distributor/cylinder alignment.
Just went through and checked all the ignition/TBI wiring for continuity to the PCM.

I have a feeling the PROM is not the original since it has a JET chip on it. However, could this be a PROM chip issue?
Recap: getting initial hit of injectors but they don't fire when cranking.

Thoughts?

 

[scott2093]

I have a feeling the PROM is not the original since it has a JET chip on it.

I've always heard it's best to get everything sorted at baseline....i.e. whatever is considered original stuff when troubleshooting...
Not sure about those chips or if any "upgrades" since it was installed could also skew things?

 

[LOTW29]

Yep, agreed. Unfortunately this is our baseline... Got the truck with this chip