Very clean install Lost in Texas! I’ve used Howell for a few EFI projects over the years and have been very happy with them for the most part. I’ve used their 8.1L harness, TBI 5.7L harness only (with no ECM tuning), and a TBI 4.3L to 7.4L project where they only did the ECM tuning. As great as a job they did with my 8.1L tuning they did an equally as horrible job with my 7.4L project. I must have spoken to Troy 50 times and each time I had to reintroduce myself and explain my issues from scratch as if he never heard my name before even after I just spent an hour on the phone with him just the day before. That kinda pissed me off! I was really suspecting they were programming the PROM to an automatic rather than a manual as mine died all the time too. After the 3rd PROM they sent they finally figured out they were indeed programming it to an automatic instead. That pissed me off even more. The truck still never ran right so I used a different tuner to burn me a PROM and vala! Fixed! On my 8.1L project I spoke with Rob at Howell which he was very helpful and made me feel he knew his shizzle. That project was a plug and play, started on the first key stroke and been driving it for almost 30,000 miles without issue. Not sure why they can’t seem to get TBI stuff to work that way anymore.
All that said, I still believe Howell is still the best game in town for harnesses and later model OBDII stock or even slightly modded tuning but they seems to have lost their way with the older TBI PROM tuning. Then again, maybe the cam and other goodies you have added to the engine are upsetting it or maybe there is still a ground issue or even a vacuum leak that has grown more annoying. Heck, a backfire followed by lower power and no restart could be a fuel delivery issue as it sounds like a lean pop then lack of fuel. Check the fuel pump connections and make sure the tank is venting. If too much pressure in the tank is present it can stop the fuel pump. My 1989 TBI Burb likes to die on really hot days when the tank is at ¼. Pop the fuel cap to relieve the pressure then keep on trucking (I really need to check the vent on that rig). Eagle Mark is good at this stuff so his recommendations are very valuable.
Again, you did a great job on your install. Hope you get it figured out soon. Be patient my friend but you may want to ask for Rob next time you call Howell. If I never speak to Troy again that would be okay with me.
