I am working on an 86 El Camino with a 350. The block number is 10066036 and comes up as a Targetmaster replacement engine for 78 to 85 cars and trucks. I don't know how it compares to a 1990 F body engine. TPI with a 7730 ECM using AUJP bin. I worked on this car for a friend back in 2018. It was the first time I used an Autoprom. The car would barely idle and stalled when I started working on it. With a lot of reading and trial and error I got the car to run fairly well and got it to the point where it was reliable and drove quite well. During this stint I installed a BBK throttle body, Accel 24lb injectors, brand new injection harness from Howell Engineering, a heated O2 sensor on the drivers side and a wideband O2 on the passenger side. Both sensors just after the collectors. It has long tube headers. with an x-pipe. I also installed a 9 inch rear with 4.10 gears. It has a 700r4. The owner drove the car summers until 2023 when something happened and caused it to run differently. I told him to bring it over and I'll have a look.
It turns out that a few shops in the area have taken a stab at working on it for him. The first thing I noticed was a remote mounted fuel pressure regulator, with the one on the rail removed and capped off. A new fuel pump has also been installed. Things were messy looking so I tested all the sensors, set the fuel pressure to 44 psi with vac line unhooked. It was set 15 psi too high. I noticed so many things wrong that I went through everything. I did a fuel pump flow test, injector and fuel rail cleaning, intake gaskets, new plugs and wires, 2 vac leaks repaired, set base timing to 6 degrees. Reset IAC. I also smoke tested the exhaust and intake system. With everything fixed up, I fired it up and took it for a ride. That quickly turned into installing a TCI adjustable TV cable and getting that all straightened out. Someone had also disconnected the 4 pin connector on the transmission and zip tied it back to the harness. I plugged it back in.
Finally, after going on a 20 mile drive I could see that the car was running okay, but as I rolled onto the throttle in the 1800 to 2400 rpm range the car would hesitate badly and the wideband pegged to 16 (Ballenger motorsports maxes out at 16 on the display). Other than that, if i rolled onto the throttle pretty quickly, it would get beyond that rpm and go back to normal. A fast stab or getting into wide open throttle didn't have any problems. After looking through the tune I did years earlier, I decided to start a new tune from a stock AUJP bin. I started off by turning off all the emissions and entering the injector data that Accel provides. I ran the car and it hesitated and went lean just the same. I turned off PE and did a log and worked on correcting VE. After correcting VE the hesitation is still there. I ended up adjusting too many settings in PE and AE as well as other things in the next few drives that I couldn't keep track of what things were helping or hurting.
The whole time working on it I couldn't help but wonder what may be causing this change in drivability since I had last worked on it. I have found out the 4.10 gears were changed out to 3.55 gears or possibly 3.27 and I am wondering if this may be the thing that has been changed on the car specifically relating to MAP change in these driving conditions. I am thinking that accelerating with a taller gearset may have created a situation where there is more load on the engine in the 2000 rpm range where this hesitation and stumbling occurs. Maybe the AE-MAP table needs work now? Has anyone else run into a similar situation?
Some other questions I also have. A couple of times the SES light has flashed 2 times and the car dies for a split second then carries on fine. When I play back the ERRORS list view I can see that moment where every single error on the list flashes for that split second. I don't see any code stored. Does anyone know what would cause this?
When uploading a new bin, is it best to clear memory first by disconnecting the battery?
Is it okay to log BLM as soon as the engine is up to temp when you upload a new bin? Or should some miles be driven first?
Some of the dashboards and monitors in Tunerpro have "in MAP AE" "in TPS AE" and "in PE" - I've never seen them active but would like to get them working if anyone can help.
I am using the newest TunerproRT release 2025, AUJP bin, S_AUJP v5 xdf and S-AUJP v5 wb adx logging a Ballenger Motorsports wideband through channel 1 of the Autoprom with a G1 adapter.
Any suggestions or help is greatly appreciated.
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