ptbentley1958

I am having the same problems with my 1999 ES300. When your P0171 (bank1) code first started coming on, did you "feel" any problem with your brakes? With the engine running, I pump my brake pedal multiple times, and it always feels spongy. When I turn the engine off and pump my brakes, the pedal does get tight. Is this normal?

Update on my p0171 code problem: After weeks of agonizing troubleshooting to solve this agravating code, I finally solved the culprit.!!! After exausting all the suggestions recieved from fellow members and talking to mechanics (each mechanic, different solution) I found where the problem was. I sat back and analized what was going on.Checked ok(A/F,Maf. Map etc. etc.) All vacumn hoses, canister, fuel pressure checked ok. I was ready to pull my hair ( What little I have left) Most indication of the lean fuel mixture was vacumn leak somewhere. Internally or intake? I very faintly hear a hissing sound near the canister, checked it (and hoses again) all ok. Where is there a very high vacumn?? Brake booster!!!!!! Cleared the code and removed the vacumn hose to the booster. Code emmediately came on. Plugged the hose and the code was gone. (No power brakes of course!!!) Code stayed off while idleing for about an hour. Replaced the booster and have driven car for about a week and the code has not returned. Apparently I had a pin hole leak in the diafram of the booster. Just enough to trigger the code. Hopes this helps someone else with the P0171 code. PS: A stetoscope would have been helpful in detecting the leak. Update on my p0171 code problem: After weeks of agonizing troubleshooting to solve this agravating code, I finally solved the culprit.!!! After exausting all the suggestions recieved from fellow members and talking to mechanics (each mechanic, different solution) I found where the problem was. I sat back and analized what was going on.Checked ok(A/F,Maf. Map etc. etc.) All vacumn hoses, canister, fuel pressure checked ok. I was ready to pull my hair ( What little I have left) Most indication of the lean fuel mixture was vacumn leak somewhere. Internally or intake? I very faintly hear a hissing sound near the canister, checked it (and hoses again) all ok. Where is there a very high vacumn?? Brake booster!!!!!! Cleared the code and removed the vacumn hose to the booster. Code emmediately came on. Plugged the hose and the code was gone. (No power brakes of course!!!) Code stayed off while idleing for about an hour. Replaced the booster and have driven car for about a week and the code has not returned. Apparently I had a pin hole leak in the diafram of the booster. Just enough to trigger the code. Hopes this helps someone else with the P0171 code. PS: A stetoscope would have been helpful in detecting the leak. I am having the same problems with my 1999 ES300. When your P0171 (bank1) code first started coming on, did you "feel" any problem with your brakes? With the engine running, I pump my brake pedal multiple times, and it always feels spongy. When I turn the engine off and pump my brakes, the pedal does get tight. Is this normal?

Most of it was trial and error. With suggestions of what the problem might be from members of the forum, I just started elimenating . After getting frustrated, I sat back and re-analized what I was doing. That is when I found the problem. I bought a new booster but had a problem with the clearence adjustment between the booster and the master cyclinder (Adjustment was very tight). I returned it and had my booster rebuilt for $175. After market (new) was $190 and dealer quoted $600. Time quoted was three hrs. at $75. per. I did it in 1.5 hrs. and a half hr bleeding the brakes.Other than that. it was just time consuming. Had to remove the air cleaner and canister and master cyclinder and connections to the brake pedel. That was the hardest. (Tight fit space) I am having the same problems with my 1999 ES300. When your P0171 (bank1) code first started coming on, did you "feel" any problem with your brakes? With the engine running, I pump my brake pedal multiple times, and it always feels spongy. When I turn the engine off and pump my brakes, the pedal does get tight. Is this normal?