- Joined
- Mar 20, 2005
- Location
- Hendersonville, NC
As part of my recent build, I pulled the old 302 out of my Ranger and swapped in a "built" one. Still a 5.0 block, same wiring etc. Not a complicated swap. But...
I installed it, got it running and running well as of the weekend before last. I even linked a video of it running. The next day I installed my full hydro, ran it for an hour to bleed the system and called it a day. Fast forward to Tuesday of last week and it started backfiring at idle and especially when revving. Now, it won't start at all, just cranks...
I help a lot of people on here with their own driveability issues and I'm pretty darn good at it but this one has me stumped. Nothing changed whatsoever between Sunday and Tuesday, just the date.
It's a 5.0 based engine, really good heads and bottom end. Cam is a custom Comp, but not much more than a good low RPM torquey one. Nothing exotic whatsoever there. 30# injectors with matching MAF.
-A9L PCM with Painless harness. They have been on the truck for years
-I have strong, consistant spark at the coil, cap and each cylinder
-I have 42 psi fuel pressure and injector pulse present on all 8 injectors
-I have 175 psi compression on all 8 (she's got some bump
)
-Cam timing and ignition timing are verified good
-I have installed known good PCM, MAF, TP, distributor, coil, plugs,etc with no success.
-No codes stored aside from the deleted emissions items. Been that way for years.
-PCM is getting the PIP signal from the module/stator
-All PCM grounds and powers have been verified
I am very well versed in the 5.0 world and this one is eating my lunch. I need it to run so I can finish it up for Harlan next weekend. Any ideas from anyone?
I installed it, got it running and running well as of the weekend before last. I even linked a video of it running. The next day I installed my full hydro, ran it for an hour to bleed the system and called it a day. Fast forward to Tuesday of last week and it started backfiring at idle and especially when revving. Now, it won't start at all, just cranks...
I help a lot of people on here with their own driveability issues and I'm pretty darn good at it but this one has me stumped. Nothing changed whatsoever between Sunday and Tuesday, just the date.
It's a 5.0 based engine, really good heads and bottom end. Cam is a custom Comp, but not much more than a good low RPM torquey one. Nothing exotic whatsoever there. 30# injectors with matching MAF.
-A9L PCM with Painless harness. They have been on the truck for years
-I have strong, consistant spark at the coil, cap and each cylinder
-I have 42 psi fuel pressure and injector pulse present on all 8 injectors
-I have 175 psi compression on all 8 (she's got some bump
![Big Grin :D :D](/styles/nc4x4/xenforo/smilies/biggrin.gif)
-Cam timing and ignition timing are verified good
-I have installed known good PCM, MAF, TP, distributor, coil, plugs,etc with no success.
-No codes stored aside from the deleted emissions items. Been that way for years.
-PCM is getting the PIP signal from the module/stator
-All PCM grounds and powers have been verified
I am very well versed in the 5.0 world and this one is eating my lunch. I need it to run so I can finish it up for Harlan next weekend. Any ideas from anyone?