Read through some threads on the TPS, and my symptoms are those of limp mode. Push the pedal all the way down but no WOT, or only able to get to 3000 rpm. Also, when the tunner reads the position of the TPS it shows it jumping around from 13-38. I hadn't seen anyone post anything about a "jumping" TPS.
He has tested the sensor and its still good, so its not that.
Where I'm really still confused is how to actually solve the problem, because some of the TPS threads actually ended up being other problems. So I got a little lost.
Is the solution to adjust the sensor using the two set screws, or is there more to it than that?
2003 BO SportDesign
SRT 2.75 / Ltuned Wheels / Koni Yellows / Eibach Springs and Sways / Alpine Sound System
This evening we are going to take some of the advice here and check the stuff out. As far as the wires that were coming from the haltech to the main harness, all looked to be in order and the soldering was not cracked in any of them.
1. Check the throttle body wires and making sure they're not burnt.
2. Check the set screw, if it was changed you can experience the limp mode from it.
3. Check the TPS sensor at idle, it should be around .6 to .7 volts. If it's not then loosen the TPS sensor and lower or increase the voltage to around .65 volts.
Thanks for all the suggestions. Looked over carefully all the wires and they seem to be in order. Also checked all the fuses and all are good as well.
I have installed the new TPS in there, but now there is a communication issue with the laptop to the F10X. We have tried several thing to connect but no dice. I am sending the F10X back to Haltech to see if they can verify and let me know if there is something wrong with the communication protocol.
So far this IS300 is beating us, but we are not giving up on it.
we loaded up the original map and the car cranked up and idled perfectly. The next big hurdle was the TPS and what it would do. As we thought it would do, the minute the accelerator was stabbed, the car would bog and die. We then tried easing into the accelerator and the car stumbled all the way through till 3k RPM. Once 3k rpm was past then car would rev like a regular car with no stumbling or hesitation.
We then remembered a setting on the haltech about the fuel pump. Coincidentally enough, there were three columns on the adjustment of fuel pump, 500rpm/1500rpm/3000rpm. Once we adjusted these, the headache and the frustration ended, for now. The car would rev like a regular car from idle. There was no need to slowly accelerate from idle to 3k rpm. We could stab it and not only would the car respond but it would also stay on after a free rev. Now that we've sorted out this issue we're gonna start tuning the car on the rollers.
Hopefully we'll get this car back to the customer's hands shortly if there are no more problems.
Customer took the car to Lexus, they tackled some issues.
Told him it was off a degree or was it a tooth, I think you told me a tooth, but in many cars being off a tooth would mean the difference in starting very erratic and not even starting at all. Well went it left to go to lexus it was starting and idleing and even driving on the dyno fine.
Well we got it back and we just had to readjust the TPS again vs the F10x.
Car was dialed in once again on the dyno. 2 sweeps where done in boost land and then we took it to the street that night to confirm the numbers (AFR) on the dyno. The boost was hitting okay, but I am sure with a little more practice on the settings and or finding a possible leak we can get it to spool much faster.
Apart from that every once in a while the o2 sensor CEL lights come on once again, which can be a PITA for every day driving. In any case the car drives fine and it pulls very hard once boost is all in.
Thanks again for everyone's suggestions and help in this forum.
Yeah I just need to play around with the SBC some more and check all my plumbing connections. But the car is still a blast to drive.
Man, i got to the house right after you left. I hope you enjoyed the ride home. The car felt much stronger on the road than on the dyno. Let me know what you thought about the car and how it felt. I'm curious. Thanks for taking your time with us on your car.
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