Multiple warning lights on

Good morning

The ABS and the trac are separate issues. There are fault codes still stored in the module.

https://www.2carpros.com/articles/abs-warning-light-on-easy-repair-guide

Most code readers will not read ABS codes. I would start by going to a parts store and have them read all the codes. Once we know the fault code for the ABS, we can help narrow the area of failure.

The 71 is a lean code for the way the engine was running.

Below are the diagnostics for the 171 code.

Roy

DTC P0171 System Too Lean (Fuel Trim)-Ex. Calif

CIRCUIT DESCRIPTION
Fuel trim refers to the feedback compensation value compared against the basic injection time. Fuel trim includes short-term fuel trim and long-term fuel trim.
Short-term fuel trim is the short-term fuel compensation used to maintain the air-fuel ratio at its ideal theoretical value. The signal from the heated oxygen sensor indicates whether the air-fuel ratio is RICH or LEAN compared to the ideal theoretical value, triggering a reduction in fuel volume if the air-fuel ratio is rich, and an increase in fuel volume if it is lean.
Long-term fuel trim is overall fuel compensation carried out long-term to compensate for continual deviation of the short-term fuel trim form the central value due to individual engine differences, wear over time and changes in the usage environment.
If both the short-term fuel trim and long-term fuel trim are LEAN or RICH beyond a certain value, it is detected as a malfunction and the MIL lights up.


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DETECTING CONDITION

HINT:
- When DTC P0171 is recorded, the actual air-fuel ratio is on the LEAN side. When DTC P0172 is recorded, the actual air-fuel ratio is on the RICH side.
- If the vehicle runs out of fuel, the air-fuel ratio is LEAN and DTC P0171 is recorded. The MIL then comes on.
- If the total of the short-term fuel trim value and long-term fuel trim value is within ± 25 %, the system is functioning normally.

Step 1
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INSPECTION PROCEDURE

HINT: Read freeze frame data using LEXUS hand-held tester or OBD II scan tool. Because freeze frame records the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining whether the vehicle was running or stopped, the engine warmed up or not, the air-fuel ratio lean or rich, etc. at the time of the malfunction.

I appreciate the response, and your time. I have had the codes read at auto parts store, and read by mechanic shops. Problem is cant seem to get the mechanics to read the fuel trims, or or look for vaccum or exhaust leaks. One mechanic performed a smoke test, and told me the vaccum hose was off, and that he fixed it, and turned off the check engine light. He wouldnt specify on the hose, didnt say anything about any leaks. Took my money and sent me on my way! The next day check engine light back on. Went to another mechanic shop. He scanned for codes, trouble codes were p0100, p0110, and p0171. He replaced the maf sensor, and air fuel ratio sensor bank 1 sensor 1, all sensors were oem Denso. He cleared the codes, gave me the car, and said like new, and sent me on my way. 80 miles later check engine light back on. Went back to this mechanic he scanned for the codes, this time only the p0171 was present. He checked sensor connections turned off check engine light and sent me on my way. 40 miles later check engine light back on. Cant get him to even look at the car again! Had oreilys auto parts scan it same code p0171 again. Keep in mind that Abs light and trac off light has not been addressed yet. Could it be a leak in the brake booster hose? I cant seem to find any mechanic shops that look for leaks all they do is scan it and throw parts at it. Got an appointment Monday with a different shop. I am on disability, and eating top Ramen noodles as mechanics keep taking my money, and not fixing the problem. All of the mechanic shops I have been to so far, were highly rated in this area. Palm coast, Florida. Thanks for any and all help.

Wow, you have been to 3 shops who dont have a clue in diagnostics.

If the booster was bad, it should have showed in a smoke test.

They did not give you the long term trims because either they either dont know what they are or they just used a code reader instead of a scan tool.

It has nothing to do with the O2 sensor.

Roy

Roy

Yes, Roy thanks again for your time. Have a. Appt. Monday morning with a different shop. Is it okay to tell them about what has already transpired? Also would it be offensive to tell them that I want them to look for vaccum leaks, and read the fuel trims? Is it acceptable to ask them what there policy is concerning if they do a repair, and that doesnt resolve the issue. What is the standard? Should they be willing to do another attempt for free or discounted, if they dont get it right the first time? Thanks for your time.

OK, first, if a shop charges you a diagnostic and charges you for repairs that did not work, you are not responsible for poor quality workmanship.

Yes, tell them all you have been through and you want specific information from the car.

Roy

Ok I will do Roy. One last question and I will let you go. I have put about 400- 500 miles on the car since I have battled this situation. I have read that driving the car with a lean condition can cause engine damage. And the shop I am going to is about 10 miles from where I stay. Considering the miles put on the car would I already have engine damage? It still seems to drive good and cranks up the first time every time. Does not stall or anything. Just trying to figure if I still have hope and should go the mechanic appointment on Monday, or get rid of the car. The car was originally a lease car, and then a guy who worked at the Lexus dealership took ownership of it. The car fax had a grip of maintenance records on it. And timing belt was done at 94,000 miles. Car is super clean and has 104k miles on it. Thank you for your valuable time.

I dont know where you read that information but that is inaccurate information. It will not damage your engine at all. It is just processing fuel correctly.

Roy

Ok Roy thanks a lot! Hope you have a great 2019! Wish you were here in my area. So I could of already got it fixed correctly. But wherever you are people are fortunate to have you around. Big thanks to 2 car pros. For having this website. If you want to know how this all pans out, I will get back to you after I go to the mechanic appt. This coming Monday. Take care.

Thank you for the kind words

We are always glad to help

Roy

New mechanic smoked tested and found leak on air intake tube.

Good find.

Make sure the long term trims are monitored to be sure they are close to 0.

Roy

New update, drove 33 miles, in town driving, and check engine light is back on.

OK, that was not it.

Can you have someone check the long term trims?

Roy

Thanks for responding back so soon. The mechanic that fixed the vaccum leak, told me to drive it around, and if check engine came back on, to bring it back in. As far as getting someone to read the Long term trims, I mentioned that to this mechanic this morning. Going to take it back to him in the morning. Trying to find a mechanic to solve the issue around here, reminds me of the old tootsie pop commercial. How many licks does it take to get to the center of a tootsie roll pop? Except in my situation, it's how many mechanics does it take to get to the bottom of this p0171 lean code? He told me that he checked the fuel pump, and that it is fine, and that the fuel filter looked old, but not restricted. Did the smoke test and found only the one vaccum leak on air intake tube. I had asked him to read the fuel trims this morning, maybe I can get him to do it tomorrow. Not to cry about the situation, but I do feel like I am in a pin ball machine. One mechanic after another. How do you make them them read the fuel trims? Do they even understand that around here? I haven't given up, I am not a quitter! I will keep you posted. Thank you for your valuable time.

I agree it is tough finding a good tech. Ask him what the exact fuel pressure was.

Roy

Okay, I will sir. I am keeping notes on everything that has been tried, and your suggestions, and everything all the mechanics have said so far. I am 53, and this situation has got me considering looking into going to mechanical school, just so I could help people not to have to go through this ordeal. I know some things can be difficult to figure out. I do not fault this latest mechanic's efforts. At least he did not tell me something outrageous and lie to me, that and at least his attempt did not cost me a fortune, that I do not have anyway. Is there away to tell if the catalytic converter is bad? Thanks for your time.You guys usually work this late? Or perhaps its earlier where you are.

It is not the catalytic converter at all. That would set the 420 code.

Roy

Thanks I am at the mechanic shop now. Waiting to see they are hooking up the scanner again.

They do not know what they are doing! So I went to Saint Augustine. I am at Amoco waiting to get a proper diagnostics. $189.00 but it comes with guarantees. He told me that if they cant figure it out he want charge me the diagnostic fee. And if they do and I get it repaired here, that after they fix it, if it comes back on with same codes they will fix it again for free, no additional charges. Does that sound legit to you? Thanks.

Yes, that sounds like a good shop that stands behind their work.

Roy

Okay. Thanks for your time, I will keep you posted, once I get their results of diagnostics. Manager said they will spend up to two hours diagnosing for the cause of p0171. Thanks. I will let you know.

They say bad brake booster.

Okay, do you hear a hissing noise from the brake pedal?

Roy

I dont have it, they have it in the bay. But not sure. They did find a hole in it, and it is rusted pretty bad.

Ask them if they verified the long term trims are back to normal with it disconnected and plugged.

If they do not return to normal, then that is not the issue.

Okay, I will ask them. Thank you.

He said that they did verify it, and it is back to. Ormal

I meant normal. Typical type with these supposed smart phones.

Okay, sounds good. Make sure they write their warranty down on the receipt.

Roy

Yes sir. One last thing. Have you ever encountered that in your career as being a fix for p0171 code? And out of all the possibilities for a lean code, where would you rank this at in percentages? Also, total cost for everything is $720.00. Any thoughts on the price? Thanks a million you are awesome. Big thumbs up to 2CarPros! They are the real deal. And they genuinely care about your mechanical issues. Good human beings! Thanks.

Here's the latest: They installed new brake booster. Just finished and now they are saying it is defective from the factory. And just had another one delivered, and are installing it.

I have less than a hand full in my 50 years.

The price is high. Rockauto has them for 175-195. The labor is around 1.5 hours or 200.

That comes out to way less than there estimate.

Roy

Yep. It figures. Well time will tell, waiting to see if check engine light comes back on. If it does for the same P0171 code they have to deal with it at their expense, not mine. If it is actually fixed, I will have well over $1,400.00 into fixing this lean code. I will let you know, I find myself constantly looking at the dash now, expecting it to come back on! But hoping it does not. Thank you for your valuable time, and information. Stay strong, and know that some of us greatly appreciate this service 2CarPros is providing us free of charge. Thanks a lot!

Thank you for the kind words.

Always glad to help.

Roy

Update on p0171 Lean code. I have 93 miles on the car since they Aamco transmission replaced the brake booster. So far no check engine light has returned. Hoping that it doesnt any time soon. As I am broke until I get paid again on March 1st.

Sounds like they got it.

Roy

I sure hope so Roy. Thanks again.

Always glad to help.

Roy