I have a 1997 SE with 130K miles.I got a p0122 code after cleaning my throttle body.I took the TPS out again and re-installed it.Still getting the code but now my tranny won't shift past 1st gear.While I had the airbox out I unplugged what I think is a PCM for the tranny.It is located in a big black box directly above the canister.It has 2 eighty pin(approx.) connectors.I also removed the chip and put it back in.I did all this because the car has been having misfires and p0171 codes.I did not disconnect the battery.My tranny was fine before I did all this.Please help.

That black box above the canister (and to the right of your airbox) holds your car'* main computer. I don't think your computer'* at fault; if you removed your throttle body, you may not have hooked up your vacuum lines correctly.

You should have these lines. Double-check against the vacuum diagram under your hood, as all this is just off the top of my head:

• EGR purge solenoid (top) to throttle body (top)
• EGR purge solenoid (bottom) to EVAP canister
• Fuel pressure regulator and transmission to throttle body (bottom), via a T-adapter

Make sure these lines are intact and not broken. That could be the cause of your P0171 code, and perhaps, your misfires.

Thanks,I'll check that in the morning as It'* raining now and my ElCamino is in the garage and starting it up might disturb the neighbors(350 with thrush mufflers).

The TPS will effect shifting because the pcm uses throttle info to determine when to shift.

First thing it appears you need is a new TPS sensor. After that, if you continue to have issues, please let us know and we can quickly direct you to the most common things. Like that P0171, if it doesn't clear soon, .... I'm an expert on that one.

Thanks Bill,I'll get back to it later in the week as I've been driving my '81 Caballero Diablo(El Camino) to work.I want to get the Bonne fixed before the weather gets hot though because my "truck" has no A/C and it'* no fun dealing with stop-and-go Brooklyn traffic with a stick shift!!!

Thanks Boosty,a new TPS did the trick.I took the car for a test run to Brooklyn last night and it ran great with no check engine light on.I filled up with gas right before getting home and the check engine light came back on.Upon arrival at home I checked my codes and the P0171 was back(somehow didn't surprise me).I cleared the code,.started the motor and it started running rough again.Looks like I'll need your expertise on P0171.I replaced the Crank Position Sensor and the Cam Sensor last saturday and checked the EGR for free pintle movement.

The P0171 is a vacuum leak. Check all the vacuum lines as well as the EGR tube. Check everything around where you were working. Spray carb cleaner around and listen for a change in RPMs.

If you have done the LIM gaskets ever, you may be able to skip the carb cleaner. Most of the time I find bad EGR tubes (from EGR to LIM), you can't get the carb clean into the right area to change idle. Pulling the tube is the best method I've found for checking it, little of a pain....but you can get very well versed after 2-3 of them.

When you check the EGR tube and if you find a crack. Please take a picture of it and send it to me. I'll make up a write up on checking the tube and use your picture.

DTC P0171 Fuel Trim System Lean

Diagnostic aids

• Heated oxygen sensor wiring. The sensor pigtail may be routed incorrectly and contacting the exhaust system.
• Poor PCM to engine block grounds. Ensure that the PCM grounds are clean, tight, and in the proper locations. Refer to Ground Distribution in Electrical Diagnosis.
• Fuel pressure. The system will go lean if pressure is too low. The PCM can compensate for some decrease. However, if fuel pressure is too low, a DTC P0171 may be set. Refer to Fuel System Pressure Test.
• Fuel injector(*): Refer to Fuel Injector Coil Test.
• Vacuum leaks. Check for the following conditions:
  • Disconnected or damaged vacuum hoses. Refer to Emission Hose Routing Diagram.
  • Incorrectly installed or malfunctioning crankcase ventilation valve. Refer to Positive Crankcase Ventilation Valve.
  • Vacuum leaks at the throttle body, EGR valve, and intake manifold mounting surfaces.
• Exhaust leaks. An exhaust leak may cause outside air to be pulled into the exhaust gas stream past the HO2S, causing the system to appear lean. Check for exhaust leaks that may cause a false lean condition to be indicated. Refer to Exhaust System .
• Mass Air Flow sensor. Disconnect the MAF sensor and see if the lean condition is corrected. If the lean condition is corrected with the MAF sensor disconnected, replace the MAF sensor. Refer to Mass Air Flow (MAF) Sensor Replacement .
• Fuel contamination. Water, even in small amounts, can be delivered to the fuel injectors. The water can cause a lean exhaust to be indicated. Excessive alcohol in the fuel can also cause this condition. Refer to Alcohol/Contaminants-in-Fuel Testing Procedure .
• Poor connection at the PCM. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
• Damaged harness. Inspect the wiring harness for damage.
• If the harness appears to be OK, observe the HO2S 1 display on the scan tool while moving connectors and wiring harnesses related to the engine harness. A change in the display will indicate the location of the malfunction.