car has 144,000 miles. I have been getting a check engine code stating, p0171 "lean." I have checked resistance on maf, map, ect, all w/ normal resistance. screwdriver to injectors I can feel and hear a solid clicking in each. I have replaced two of the 3 coil ignition packs. Replaced wires and plugs three months ago and fuel filter month ago. I am not getting any power out of the car. When I try to accelerate, I get a Putt putt putt sound, hesitation and it wont go above 40. I can hear an exhaust leak in the rear of engine. for a few months I have been dealing wit this. when the engine ligt comes on the car starts burning very rich and the smell becomes unbearable. I have been resetting the computer by removing the negative battery cable. then the car seems to go back to normal. however, now there is no difference even though the light is on or off. Please... Any advice would be most helpful!!!!!
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1998 Toyota Camry Question: lean code. now little to no acceleration with sputtering/ hesitation
Answer #1ZeeTech September 17, 2010, 12:07Master
Start with the basics first. Compression and fuel pressure are confirmed and good?
No intake leaks at all?
Resistance on MAF and MAP doesn't mean the sensing element actually working. Can you see live data through ECM? When you disconnect the MAF it works better?
When you reset the ECM it works perfectly until code returns?
What about O2 sensor readings? Can you check the wave form of it?
Answer #2The Car Doctor from The Car Doctor, LLC, September 18, 2010, 01:06Technician
Is the exhaust leak before the 02 sensor. If so, that would throw off the sensor readindg and cause a hesitation. If not,it could be many things, but most likely its either an intake gasket leak or an o2 sensor. Spray some carb cleaner on the intake gaskets while the engine is running. If there is a change in RPMs, you've got a leak. If not, its probably an o2 sensor because if it were anything else it would likely have bank 2 lean code or misfire codes. Be careful because some camrys w/ cali emissions have air/fuel sensors instead of o2 sensors. If that is the case, you should only use a Toyota part and replacing it w/o confirmation is an expensive guess. Let me know if you have any more questions.
ReplyVisitor, October 03, 2010, 10:53
I thank you guys for your helpful tips... Unfortunately I had already done all that. The freakiest cause though... mI cut out the Y pipe with the two cats in it. apparantly, the third cat, (front of engine connected to the exhaust manifold), well the insides of this cat compressed and broke off, lodging itself into the front of the y pipe and backing up the front half of the exhaust system. Only one other person has ever seen/heard of this. And since there was a good amount of exhaust still coming out of tailpipe, who would have thought to do a smoke test. So keep that one in the back of your heads if this situation should arise by you. I replaced the entire exhaust system, less the rear exhaust manifold and now it is running like new, (of course prior I did the plugs, wires, coil packs, maf sensor, 2 air/fuel ratio sensors and the rear o2 sensor. ) gotta love cars right!!!