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-   -   Help! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-1110753/)

profc3s 02-18-17 12:48 AM

Help!
 
First of all i searched a ton for my problem abut to no avail. Basically would start then die. If I give it a little throttle it would rev up to 4K then hit a wall then die. If I feather the throttle like 10-20% it would stay running until i stop then die.

Car Specs
1991 JDM GT-X S5
No AFM
Downpipe
GM 3-Bar MAF sensor
FD IAT Sensor
AP Engineering Power FC
Banzai Racing S5 Power FC harness

So in a nutshell before installing all of above items my car was going into limp mode. I would go past 30% throttle and it felt like it hit a wall. Swapped out my spark plugs and wires. My aftermarket boost gauge would not go past 0. Searched the forums and boom I thought it was an OMP. I did the ohms checks for the stepper motor on it and they were not it specs. It also burnt a resistor in my ECU.Swapped out my OMP and got a known working ECU, It didn't fix the problem. Swapped out my TPS to a known good one, it didn't fix the problem. Swapped out my fuel pump to a walbro 255, didn't fix the problem. I got frustrated so I bought an AP engineering power fc and installed it with the Banzai Racing kit. Didn't fix the problem. So i'm back to square one. Read through the factory service manual but i'n still at a loss. I wiped whatever tune that it had on the FC so that i can drive it to the tuner. Any help would be appreciated guys. I usually fix 99% of the problems with the factory service manual/Haynes/google search but i am at a loss with this one.

Banzai-Racing 02-18-17 07:11 AM

post up screen shots of the sensor switch screen and the monitor screen

RotaryEvolution 02-18-17 08:08 AM

the PFC doesn't have a limp mode, so it won't ever be the OMP giving you grief.

your car probably has the wrong map either for the car setup or for the 3 BAR map. when you say you wiped the map, you should specify if the problem arose before or after... the default map will not be set properly for a GM 3 BAR sensor, and by your description it sure sounds like the MAP sensor settings are off or are running a bit larger injectors than the ECU was mapped for.

profc3s 02-18-17 11:44 PM

Here are the pics


https://cimg9.ibsrv.net/gimg/www.rx7...b46c53d1a2.jpg


https://cimg2.ibsrv.net/gimg/www.rx7...a8839e1972.jpg


https://cimg4.ibsrv.net/gimg/www.rx7...9a15b4cc51.jpg

profc3s 02-18-17 11:53 PM


Originally Posted by RotaryEvolution (Post 12153384)
the PFC doesn't have a limp mode, so it won't ever be the OMP giving you grief.

your car probably has the wrong map either for the car setup or for the 3 BAR map. when you say you wiped the map, you should specify if the problem arose before or after... the default map will not be set properly for a GM 3 BAR sensor, and by your description it sure sounds like the MAP sensor settings are off or are running a bit larger injectors than the ECU was mapped for.

So when I tried to start the car with the map the last owner put in for me. It didn't work. Then I did the factory reset on the Power FC. My tuner is gonna come over and put a map i got from Chris @ Banzai Racing then well go from there. Also on the commander i noticed under Air temp there were 4 asterics w/ 4.98 volts going to it. Isn't there suppose to be like fuel temp or something?

RotaryEvolution 02-19-17 12:40 AM

i don't recall what that line was used for.

you will be stuck waiting for a datalogit map upload in the meantime, as that's the only way to really adjust the MAP sensor PIM's. trying to adjust the injector trim might get it going but you'd be lucky to get anything besides an idle.

profc3s 02-19-17 02:19 AM

Cool. ill update after i upload a map.

misterstyx69 02-19-17 08:22 AM

There is also a PFC section that you can post in that guys would be better familiar with the unit that you have.
The members that own one may be able to help you solve the issue.

GoodfellaFD3S 02-19-17 08:38 AM

I'm familiar with the FD PFC, some of the things I'm seeing on your screen shots are a bit different. You're correct, the four asterisks are where fuel temp typically is located.

One problem is the -226 mmHg as a baseline with the car off...... should be around -30, give or take based on elevation.

Rotary Evolution nailed it earlier in the thread. Car needs the proper scale and offset for the GM 3 bar Map sensor. Looks like you have it set for the Apex'i 3 Bar Map sensor. Without a datalogit you can try swapping to one of those and see if that works for you :icon_tup:

profc3s 02-24-17 10:02 PM

*Update*

Just got done with my tuner setting up the power fc. Loaded up the map I got from Chris @ Banzai Racing. Started up and idled just fine. Did the 10/10/10 min idle learning. Since there is absolutely ZERO dyno's around the are we had to resort to a "street tune". Got everything done! Now i have to fix some small vacs leaks and get a new battery because my car's been sitting a while. But other than that she works absolutely fine.

Big thanks to Chris @ Banzai, Rotary Evolution, and GoodfellaFD3S for all the good info and help.

RotaryEvolution 02-24-17 10:05 PM

street tunes are ideal, real world allowances in the map. i prefer dyno tuning only because it is safer(for people, not the tune) and quicker, plus i won't get any speeding or reckless driving tickets...


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